piperidines and lafutidine

Burning mouth syndrome (BMS) refers to chronic orofacial pain, unaccompanied by mucosal lesions or other evident clinical signs. It is observed principally in middle-aged patients and postmenopausal women. BMS is characterized by an intense burning or stinging sensation, typically on the tongue or in other areas of the oral mucosa. It can be accompanied by other sensory disorders such as dry mouth or taste alterations. Probably of multifactorial origin, and often idiopathic, with a still unknown etiopathogenesis in which local, systemic and psychological factors are implicated. Currently there is no consensus on the diagnosis and classification of BMS. This study reviews the literature on this syndrome, with special reference to the etiological factors that may be involved and the clinical aspects they present. The diagnostic criteria that should be followed and the therapeutic management are discussed with reference to the most recent studies.

Topics: Acetamides; Amines; Anti-Anxiety Agents; Antidepressive Agents; Antioxidants; Burning Mouth Syndrome; Chlordiazepoxide; Clonazepam; Cognitive Behavioral Therapy; Cyclohexanecarboxylic Acids; Female; Gabapentin; gamma-Aminobutyric Acid; Histamine H2 Antagonists; Humans; Male; Paresthesia; Peripheral Nervous System Diseases; Phantom Limb; Piperidines; Prognosis; Pyridines; Sex Factors; Thioctic Acid; Tongue; Xerostomia

Potent antisecretory agents, such as histamine H2-receptor antagonists and proton pump inhibitors, have achieved great improvement in peptic ulcer therapy. It has, however, been reported that incidence of ulcer relapse is high after discontinuation of these drugs. Insufficient efficacy against NSAID-induced ulcers is also critical. Lafutidine is a novel histamine H2 antagonist with gastroprotective activity. Lafutidine exhibited potent and long-lasting H2 antagonism and prolonged antisecretion. In addition, lafutidine showed a gastroprotective effect against noxious agents-induced gastric mucosal damage through capsaicin-sensitive afferent nerves. Lafutidine showed antiulcer activities against acute ulcer models, prevented gastric ulcer relapse of acetic ulcer, and accelerated the healing of indomethacin-induced antral ulcers in rats. These results suggest the advantage of the combined antisecretory and gastroprotective activities. In clinical studies, lafutidine showed prolonged antisecretion, healing effect against gastric and duodenal ulcers and gastritis, and its potency was equal or superior to that of conventional H2 antagonists. Additionally, lafutidine induced a high transition rate to the E0 stage determined by endoscopical ultrasonography, suggesting the high quality of ulcer healing. Furthermore, effectiveness of lafutidine against NSAIDs-induced ulcer was high. From these results, lafutidine is equal or superior to conventional H2 antagonists in antiulcer potency, and it may be useful for the prevention of ulcer relapse and or treatment of NSAIDs-induced gastroduodenal damage.

Topics: Acetamides; Animals; Anti-Ulcer Agents; Gastric Acid; Gastric Mucosa; Histamine H2 Antagonists; Humans; Peptic Ulcer; Piperidines; Pyridines; Rats

Vonoprazan, a novel potassium-competitive acid blocker, elicits potent acid inhibition and hypergastrinemia at a dose of 20 mg. Its recommended maintenance dose for gastro-esophageal reflux disease is 10 mg, which is sometimes insufficient for preventing nocturnal acid breakthrough (NAB). Concomitant use of a histamine 2 receptor antagonist (H. The aim of this study is to compare the levels of acid inhibition and serum gastrin attained by addition of lafutidine to vonoprazan 10 mg with levels after a dose increase of vonoprazan from 10 to 20 mg.. Thirteen healthy volunteers underwent 24-h intragastric pH monitoring and serum gastrin measurements on day 7 of three different regimens: vonoprazan 10 mg, vonoprazan 10 mg plus lafutidine 10 mg, and vonoprazan 20 mg.. Median pH 4 holding time ratios (range) by vonoprazan 10 mg, vonoprazan 10 mg plus lafutidine 10 mg, and vonoprazan 20 mg were 82% (47-88%), 88% (76-93%), and 99% (95-100%) while those at nighttime from 10 p.m. to 8 a.m. were 94% (29-100%), 100% (95-100%), and 100%, respectively. The incidences of NAB with vonoprazan 10 mg, vonoprazan plus lafutidine, and vonoprazan 20 mg were 38, 8, and 0%, respectively. Respective serum gastrin levels were 420 (173-508), 323 (196-521), and 504 (400-812) pg/ml.. Addition of lafutidine 10 mg to vonoprazan 10 mg achieved sufficient acid inhibition, especially at nighttime, without further increase of serum gastrin levels.

Topics: Acetamides; Adolescent; Adult; Cross-Over Studies; Dose-Response Relationship, Drug; Drug Therapy, Combination; Female; Gastric Acid; Gastric Acidity Determination; Gastrins; Gastroesophageal Reflux; Healthy Volunteers; Histamine H2 Antagonists; Humans; Hydrogen-Ion Concentration; Male; Piperidines; Proton Pump Inhibitors; Pyridines; Pyrroles; Sulfonamides; Young Adult

Topics: Acetamides; Adolescent; Adult; Drug Therapy, Combination; Female; Histamine H1 Antagonists; Histamine H2 Antagonists; Humans; Male; Non-Neuronal Cholinergic System; Piperidines; Pyridines; Quality of Life; Urticaria; Young Adult

To compare the clinical efficacy of the second-generation H2RA lafutidine with that of lansoprazole in Japanese patients with mild gastroesophageal reflux disease (GERD).. Patients with symptoms of GERD and a diagnosis of grade A reflux esophagitis (according to the Los Angeles classification) were randomized to receive lafutidine (10 mg, twice daily) or lansoprazole (30 mg, once daily) for an initial 8 wk, followed by maintenance treatment comprising half-doses of the assigned drug for 24 wk. The primary endpoint was the frequency and severity of heartburn during initial and maintenance treatment. The secondary endpoints were the sum score of questions 2 and 3 in the Gastrointestinal Symptom Rating Scale (GSRS), and the satisfaction score.. Between April 2012 and March 2013, a total of 53 patients were enrolled, of whom 24 and 29 received lafutidine and lansoprazole, respectively. After 8 wk, the frequency and severity of heartburn was significantly reduced in both groups. However, lafutidine was significantly inferior to lansoprazole with regard to the severity of heartburn during initial and maintenance treatment (P = 0.016). The sum score of questions 2 and 3 in the GSRS, and satisfaction scores were also significantly worse in the lafutidine group than the lansoprazole group (P = 0.0068 and P = 0.0048, respectively).. The clinical efficacy of lafutidine was inferior to that of lansoprazole, even in Japanese patients with mild GERD.

Topics: Acetamides; Adult; Aged; Aged, 80 and over; Esophagitis, Peptic; Female; Gastroesophageal Reflux; Heartburn; Histamine H2 Antagonists; Humans; Japan; Lansoprazole; Male; Middle Aged; Piperidines; Proton Pump Inhibitors; Pyridines; Severity of Illness Index; Treatment Outcome

There has been no study on the efficacy of lafutidine for patients with reflux esophagitis in Korea.. To evaluate the efficacy of a new-generation histamine-2 receptor antagonist, lafutidine, in comparison with famotidine in patients with reflux esophagitis.. This was a randomized, double-blind, non-inferiority trial enrolling patients with erosive esophagitis. The efficacy and safety of 20 mg lafutidine (treatment group) were compared with those of 40 mg famotidine (control group) and 20 mg omeprazole (reference group). The primary endpoint was the complete healing rates of reflux esophagitis on endoscopy after 8 weeks of treatment. The non-inferiority margin was assumed to be -15 %.. The healing rates of reflux esophagitis on endoscopy after 8 weeks of treatment were 70.14 % (101/144) in the lafutidine, 63.45 % (92/145) in the famotidine, and 85.71 % (126/147) in the omeprazole group. The difference in healing rates between the lafutidine and famotidine groups was 6.69 % (95 % confidence interval = [-4.14 to 17.52]). In addition, lafutidine was superior to famotidine in clinical improvement (53.73 % vs. 39.55 %, P = 0.0200).. Lafutidine was non-inferior to famotidine in healing of reflux esophagitis. Lafutidine, however, was superior to famotidine in terms of symptom relief of reflux esophagitis.

Topics: Acetamides; Adult; Aged; Anti-Ulcer Agents; Double-Blind Method; Esophagitis, Peptic; Esophagoscopy; Famotidine; Female; Humans; Male; Medication Adherence; Middle Aged; Omeprazole; Piperidines; Pyridines; Republic of Korea; Severity of Illness Index; Treatment Outcome

The present study evaluated the efficacy of lafutidine, a histamine H2 receptor antagonist, for reducing gastrointestinal toxicities during adjuvant chemotherapy using oral fluorouracil anticancer drugs for gastric cancer.. Patients with stage II (T1 cases excluded) or stage III gastric adenocarcinoma who underwent gastrectomy with D2 lymphadenectomy achieving R0 resection from 2011 to 2013 were prospectively enrolled in the study. Patients were randomly assigned to either S-1 treatment or S-1 plus lafutidine treatment. Quality of life and gastrointestinal toxicity were evaluated before chemotherapy and at 2, 4, and 6 weeks after the beginning of treatment.. The incidence of diarrhea during chemotherapy was significantly lower in the S-1 plus lafutidine group than in the group treated with S-1 alone (10% vs. 83%, respectively; p=0.002). The grades of diarrhea and nausea during chemotherapy were also significantly lower compared to those before chemotherapy in patients receiving S-1 plus lafutidine than in those administered S-1 alone. The rate of patients requiring a dose reduction or interruption of S-1 was significantly lower in the S-1 plus lafutidine group than in the group treated with S-1 alone (30% vs. 83%, respectively; p=0.027).. Lafutidine might be useful not only for preventing gastrointestinal toxicities during adjuvant chemotherapy for gastric cancer, but also for improving compliance with taking oral fluorouracil anticancer drugs. However, this indication needs to be confirmed in a larger, prospective, randomized, controlled trial.

Topics: Acetamides; Adenocarcinoma; Aged; Aged, 80 and over; Antimetabolites, Antineoplastic; Antineoplastic Combined Chemotherapy Protocols; Chemotherapy, Adjuvant; Diarrhea; Drug Combinations; Female; Fluorouracil; Gastrectomy; Gastrointestinal Tract; Histamine H2 Antagonists; Humans; Lymph Node Excision; Male; Middle Aged; Nausea; Oxonic Acid; Piperidines; Prospective Studies; Pyridines; Quality of Life; Stomach Neoplasms; Tegafur

Lafutidine, an antagonist of histamine H2-receptor, has gastroprotective activity associated with activation of capsaicin-mediated sensory nerves. The objective of this study was to investigate the efficacy of lafutidine for the treatment of taxane-induced peripheral neuropathy in patients with gynecological malignancies.. Twenty patients with taxane-induced peripheral neuropathy during the treatment of gynecological malignancy were enrolled in this study. After obtaining their informed consent, lafutidine (20mg per day) was administered orally, the efficacy of which was assessed according to the Patient Neurotoxicity Questionnaire item 1.. Significant, moderate, slight, and no effects were observed in four, five, five, and six patients, respectively. The efficacy including significant and moderate effect was observed in nine (45%) of the 20 patients (95% confidence interval, 25.8%-65.8%). No adverse effects due to lafutidine were observed.. This pilot study supports the relatively high efficacy of lafutidine for the treatment of taxane-induced peripheral neuropathy. Further prospective studies are warranted.

Topics: Acetamides; Aged; Aged, 80 and over; Antineoplastic Agents; Bridged-Ring Compounds; Female; Genital Neoplasms, Female; Histamine H2 Antagonists; Humans; Middle Aged; Peripheral Nervous System Diseases; Piperidines; Pyridines; Taxoids

Lafutidine is an H2-receptor antagonist with gastroprotective action through capsaicin-sensitive afferent neurons and relatively inexpensive compare to proton-pump inhibitors (PPIs). A 7-day course of PPIs-amoxicillin-metronidazole is recommended as standard second-line Helicobacter pylori therapy and is covered by national health insurance in Japan. The aim of this study was to determine the efficacy and safety of second-line eradication using the H2-receptor antagonist lafutidine as a substitute for a PPI..  Fifty-two patients who failed in first-line eradication using PPI-amoxicillin-clarithromycin were randomly assigned to a 7-day course of rabeprazole at 10 mg b.i.d., amoxicillin at 750 mg b.i.d., and metronidazole at 250 mg b.i.d. (RPZ-AM) or a 7-day course of lafutidine at 10 mg t.i.d., amoxicillin at 750 mg b.i.d., and metronidazole at 250 mg b.i.d. (LFT-AM) as second-line therapy. Eradication was assessed by the (13) C urea breath test. A drug susceptibility test was performed before the second-line therapy..   Prior to second-line H. pylori eradication, the rate of resistance to clarithromycin was 86.5% and the rate of resistance to metronidazole was 3.8%. The eradication rates for both LFT-AM and RPZ-AM groups were 96% (95%CI = 88.6-100%). There were no severe adverse events in either group.. Lafutidine plus metronidazole-amoxicillin as second-line therapy provided a high eradication rate and safe treatment similar to a PPI-based regimen. Lafutidine-based eradication therapy is therefore considered to be a promising alternative and is also expected to reduce health care costs in H. pylori eradication.

Topics: 2-Pyridinylmethylsulfinylbenzimidazoles; Acetamides; Adult; Aged; Amoxicillin; Anti-Bacterial Agents; Drug Therapy, Combination; Female; Helicobacter Infections; Helicobacter pylori; Humans; Male; Metronidazole; Middle Aged; Pilot Projects; Piperidines; Pyridines; Rabeprazole; Time Factors; Young Adult

To evaluate the efficacy of lafutidine (20mg) , famotidine (40mg) and placebo in patients with mild reflux esophagitis (Grades A and B according to the Los Angeles classification) , a double-blind, multicenter, randomized clinical trial was performed for the first time in Japanese patients. In addition to each physician's evaluation, efficacy was evaluated by judging panels using images submitted by each physician. The healing rate after 8 weeks for lafutidine, famotidine and placebo were 67.7%, 56.6% and 41.2%, respectively. Lafutidine was significantly more effective than placebo (p=0.002, according to the judging panels) . Based on the evaluation of endoscopic images by the judging panels, 91 (27.1%) of 336 images submitted by each physician were judged to not be mucosal breaks. Judging panels are considered one of the ways to resolve the problem of the need to unify the criteria.

Topics: Acetamides; Adult; Aged; Asian People; Esophagitis, Peptic; Famotidine; Female; Histamine H2 Antagonists; Humans; Male; Middle Aged; Piperidines; Pyridines

This randomized, double-blind, controlled study examined whether lafutidine is superior to placebo and non-inferior to famotidine in terms of healing rates as assessed by endoscopy in Japanese patients with mild reflux esophagitis. Safety and improvement in symptoms of heartburn were also assessed.. Patients with an endoscopic diagnosis of grade A or B reflux esophagitis according to the Los Angeles classification were randomly assigned to receive lafutidine (20 mg/day), famotidine (40 mg/day), or placebo for 8 weeks.. Of the 584 patients enrolled in the study, 447 were diagnosed to have grade A or B reflux esophagitis by the Endoscopic Assessment Committee. Healing rates at 8 weeks were 71.0% (115/162) in the lafutidine group, 61.4% (86/140) in the famotidine group, and 9.7% (14/145) in the placebo group. Lafutidine was thus demonstrated to be superior to placebo and non-inferior to famotidine. As compared with placebo, lafutidine significantly improved symptoms of heartburn.. Lafutidine has a high endoscopic healing rate and improves symptoms of heartburn in patients with mild reflux esophagitis. Lafutidine is considered a promising treatment option for mild reflux esophagitis.

Topics: Acetamides; Double-Blind Method; Esophagitis, Peptic; Esophagoscopy; Famotidine; Female; Heartburn; Histamine H2 Antagonists; Humans; Japan; Male; Middle Aged; Piperidines; Pyridines; Treatment Outcome

The attenuated antisecretory activity of H2-receptor antagonists (H2RA) during continuous administration is referred to as the tolerance phenomenon. A previous study indicated that Helicobacter pylori (H. pylori) infection prevents the occurrence of tolerance to H2RA. In the present study, we investigated whether intermittent (every other day) administration prevents the tolerance phenomenon in H. pylori-negative patients.. Ten H. pylori-negative, healthy volunteers were included in the study. All of the patients underwent two courses of H2RA (lafutidine) administration: 21-day continuous administration (every day), followed by 21-day intermittent administration (every other day), with at least a 21-day lafutidine-free period between the first and second courses. All of the patients were examined by ambulatory intragastric pH monitoring five times: before medication, and on days 1 and 21 of the first (continuous) and second (intermittent) courses of lafutidine (10 mg b.d.) in a crossover fashion.. The continuous administration of lafutidine had a significantly attenuated, acid-suppressing effect in H. pylori-negative patients, and showed evidence of the tolerance phenomenon. However, the tolerance phenomenon was not observed through intermittent administration.. These results demonstrated that in H. pylori-negative patients, tolerance to H2RA, induced by continuous lafutidine administration, was reversed by subsequent intermittent administration.

Topics: Acetamides; Adult; Anti-Ulcer Agents; Cross-Over Studies; Drug Administration Schedule; Drug Tolerance; Gastric Acid; Gastric Acidity Determination; Gastric Mucosa; Histamine H2 Antagonists; Humans; Japan; Male; Middle Aged; Piperidines; Pyridines; Time Factors

The concomitant use of non-steroidal anti-inflammatory drugs is a risk factor for low-dose aspirin (LDA)-associated upper gastrointestinal toxicity. Lafutidine is an H2-receptor antagonist with gastroprotective activity, produced by acting on capsaicin-sensitive afferent neurons. To evaluate the preventive effect of lafutidine on gastric damage caused by LDA alone and by the combination of both LDA and loxoprofen, we conducted a clinical study using healthy volunteers.. A randomized, double-blinded, placebo-controlled, crossover study was carried out. Sixteen healthy volunteers without Helicobacter pylori infection were randomly assigned to two groups. Both groups received 81 mg of aspirin once daily for 14 days (on days 1 to 14) and 60 mg of loxoprofen three times daily for the last 7 days (on days 8 to 14). Placebo or 10 mg of lafutidine was administered twice daily for 14 days in each group. After a 2-week washout period, placebo and lafutidine were crossed over. Endoscopic findings of gastric mucosal damage were evaluated according to the modified Lanza score.. The mean modified Lanza score was 2.19 ± 1.06 (SD) for aspirin plus placebo as compared with 0.50 ± 0.77 for aspirin plus lafutidine (P < 0.001), and 3.00 ± 1.56 for aspirin plus loxoprofen and placebo as compared with 1.25 ± 1.37 for aspirin plus loxoprofen and lafutidine (P < 0.01).. The addition of loxoprofen to LDA increases gastric mucosal damage. Standard-dose lafutidine significantly prevents gastric mucosal damage induced by LDA alone or LDA plus loxoprofen in H. pylori-negative volunteers. Larger controlled studies are needed to strengthen these findings.

Topics: Acetamides; Administration, Oral; Adult; Anti-Inflammatory Agents, Non-Steroidal; Aspirin; Cross-Over Studies; Cyclooxygenase Inhibitors; Dose-Response Relationship, Drug; Double-Blind Method; Endoscopy, Gastrointestinal; Female; Gastric Mucosa; Histamine H2 Antagonists; Humans; Male; Phenylpropionates; Piperidines; Pyridines; Stomach Diseases; Treatment Outcome; Young Adult

Lafutidine is a unique histamine H(2)-receptor antagonist (H2RA) that has a sensitizing effect on capsaicin-sensitive afferent neurons (CSAN). This effect may make lafutidine useful for the treatment of burning mouth syndrome (BMS).. To evaluate the efficacy and safety of lafutidine in patients with oral burning sensation, a randomized controlled trial was performed. Patients who had been receiving other H2RAs with no sensitizing effect on CSAN were randomly assigned to receive lafutidine 10 mg twice daily for 12 weeks, instead of the previous H2RAs, plus gargling with azulene sulfonate sodium (ASS) (lafutidine group, n = 36) or to continue to receive the previous H2RAs plus ASS gargling (control group, n = 35). The intensity of burning sensation was scored by means of a visual analog scale (VAS).. Thirty-four patients in the lafutidine group and 30 in the control group completed the study. In the lafutidine group, the rate of improvement in the VAS score as compared with the baseline value was significant after 4, 8, and 12 weeks of treatment (P < 0.05). The improvement rate was consistently higher in the lafutidine group than in the control group; the differences between the groups were significant (P < 0.05) after 4, 8, and 12 weeks of treatment. Only two mild abdominal adverse events occurred in the lafutidine group, but neither required the termination of treatment.. Oral lafutidine is very safe and effective for reducing the intensity of oral burning sensation and may therefore be a viable option for the treatment of BMS.

Topics: Acetamides; Aged; Burning Mouth Syndrome; Capsaicin; Female; Histamine H2 Antagonists; Humans; Male; Neurons, Afferent; Pain Measurement; Palliative Care; Piperidines; Pyridines; Sensory System Agents; Treatment Outcome

The ideal medication for treatment of acid related diseases should have a rapid onset of action to promote hemostasis and resolution of symptoms. The aim of our study was to investigate the inhibitory effects on gastric acid secretion after a single oral administrations of lafutidine, is a newly synthesized H2-receptor antagonist, with mosapride 5 mg or lafutidine alone.. Ten Helicobacter pylori negative male subjects participated in this randomized, two-way crossover study. Intragastric pH was monitored continuously for 4 hours after a single oral administration of lafutidine 10 mg or lafutidine 10 mg with mosapride 5 mg (the lafutidine being administrated one hour after the mosapride). Each administration was separated by a 7-day washout period.. The average pH during the 4-hour period after administration of lafutidine 10 mg with mosapride 5 mg was higher than after lafutidine 10 mg alone (median: 5.25 versus 4.58, respectively; p = 0.0318). During the 3-4 hour study period, lafutidine 10 mg with mosapride 5 mg provided a higher pH, compared to lafutidine 10 mg alone (median: 7.28 versus 6.42; p = 0.0208).. In H. pylori negative healthy male subjects, an oral dose of lafutidine 10 mg with mosapride 5 mg more rapidly increased intragastric pH than lafutidine 10 mg alone.

Topics: Acetamides; Administration, Oral; Adult; Anti-Ulcer Agents; Benzamides; Cross-Over Studies; Dose-Response Relationship, Drug; Drug Therapy, Combination; Gastric Acid; Gastric Mucosa; Histamine H2 Antagonists; Humans; Hydrogen-Ion Concentration; Male; Morpholines; Piperidines; Pyridines; Stomach; Time Factors

Lafutidine is a novel H(2)-receptor antagonist with gastroprotective activity that includes enhancement of gastric mucosal blood flow. The aim of the present study was to test the efficacy of 7- or 14-day lafutidine-clarithromycin-amoxicillin therapy versus a lansoprazole-based regimen for Helicobacter pylori eradication.. Four hundred and sixty-three patients with H. pylori-infected peptic ulcer disease were randomized to one of four regimens: (1) lafutidine (20 mg b.i.d.), clarithromycin (500 mg b.i.d.) and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LFT group) or (2) for 14 days (the 14LFT group); (3) lansoprazole (30 mg b.i.d.), clarithromycin (500 mg b.i.d.), and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LPZ group); or (4) for 14 days (the 14LPZ group). The eradication rates, drug compliance, and adverse effects among the four regimens were compared.. The eradication rates by the intention-to-treat and per-protocol analyses in the 7LFT and 7LPZ groups were 76.5% and 81.6%, and 76.9% and 82.0% (p = .94 and .95), respectively. The eradication rates by intention-to-treat and per-protocol analyses in the 14LFT and 14LPZ groups were 78.2% and 82.2%, and 80.4% and 85.9% (p = .70 and .49), respectively. The treatment duration for 7 days or 14 days did not affect the eradication rates. In addition, the adverse effect rates and discontinuation rates were similar among the four groups. Furthermore, the ulcer cure rate and symptom response rate were similar in the lafutidine and lansoprazole groups.. The results of this study showed that lafutidine-clarithromycin-amoxicillin therapy was a safe and effective as lansoprazole-based triple therapy for the eradication rate of H. pylori, and could be considered as an additional treatment option.

Topics: 2-Pyridinylmethylsulfinylbenzimidazoles; Acetamides; Adult; Aged; Amoxicillin; Anti-Bacterial Agents; Anti-Ulcer Agents; Clarithromycin; Female; Helicobacter Infections; Helicobacter pylori; Humans; Korea; Lansoprazole; Male; Middle Aged; Piperidines; Pyridines; Time Factors; Treatment Outcome

To compare the antisecretory activity and plasma drug concentrations of a single oral dose of 10 mg lafutidine, a novel H2 receptor antagonist, with those of the proton pump inhibitor lansoprazole (LPZ) 30 mg.. Ten volunteers without H pylori infection participated in this crossover study comparing lafutidine 10 mg with LPZ 30 mg. Intragastric pH was monitored for 6 h in all participants, and blood samples were collected from four randomly selected individuals after single-dose administration of each drug.. The median intragastric pH was significantly higher in individuals who received lafutidine 10 mg than in those who received LPZ 30 mg 2, 3, 4, 5, and 6 h after administration. Maximal plasma drug concentration was reached more promptly with lafutidine 10 mg than with LPZ 30 mg.. In H pylori-negative individuals, gastric acid secretion is more markedly inhibited by lafutidine than by LPZ.

Topics: 2-Pyridinylmethylsulfinylbenzimidazoles; Acetamides; Administration, Oral; Adult; Aryl Hydrocarbon Hydroxylases; Cross-Over Studies; Cytochrome P-450 CYP2C19; Gastric Acid; Gastric Acidity Determination; Gastric Mucosa; Genotype; Histamine H2 Antagonists; Humans; Hydrogen-Ion Concentration; Lansoprazole; Male; Middle Aged; Piperidines; Proton Pump Inhibitors; Pyridines

Even with the most effective treatment, Helicobacter pylori eradication is difficult in some patients. Therefore, patients sometimes require acid-suppressive therapy without H. pylori eradication. It has been reported that ranitidine inhibits neutrophil activation, whereas famotidine does not. However, few studies have been published concerning the activation of neutrophils before and after treatment using clinical doses of histamine-2 receptor antagonists in patients with H. pylori infection.. To examine the effects of neutrophil activation after treatment with three different histamine-2 receptor antagonists.. This prospective, open-label, randomised, parallel-group study was conducted. Thirty patients with H. pylori infection were enrolled. These subjects were randomly assigned to receive one of the following treatments: (a) 150 mg ranitidine, (b) 20mg famotidine, or (c) 10 mg lafutidine b.d., for 4 weeks. Before and after histamine-2 receptor antagonist treatment, histological findings, myeloperoxidase activity, and interleukin-8 in the gastric mucosa were evaluated.. On the basis of the histological findings between before and after histamine-2 receptor antagonist treatment, no significant differences were found in any groups. Similarly, there were no significant differences in myeloperoxidase activity or interleukin-8 levels.. In patients with H. pylori, when used at clinical doses, any histamine-2 receptor antagonists can be used without concerning about inhibition of neutrophil activation.

Topics: Acetamides; Adult; Dyspepsia; Famotidine; Female; Helicobacter Infections; Helicobacter pylori; Histamine H2 Antagonists; Humans; Interleukin-8; Male; Middle Aged; Neutrophil Activation; Peroxidase; Piperidines; Pyridines; Ranitidine

There has been no study attempting to compare the effects of lafutidine, a novel H2-receptor antagonist and other H2-receptor antagonists in the same subjects and relating them to H. pylori status. The first aim of this study was to investigate the effect of H. pylori status on intragastric pH in healthy volunteers receiving lafutidine or famotidine. The second aim was to compare the effects of the two antisecretory drugs.. The study was carried out in 11 healthy asymptomatic male volunteers. H. pylori infection was present in 5 subjects. Subjects were first examined by an ambulatory pH monitoring for 24 hours without medication. The second and third 24-hour pH monitoring study was performed on all subjects. Subjects took 10 mg lafutidine or 20mg famotidine at 9:00 and 21:00.. During administration of lafutidine or famotidine, the percentage of period holding intragastric pH >4 was not significantly different between the H. pylori-negative and -positive subjects. Among the H. pylori negative subjects, the percentage of daytime period holding intragastric pH >4 was significantly greater with lafutidine than with famotidine (p < 0.05).. The effect of lafutidine to increase intragastric pH was not affected by the H. pylori status. Among H. pylori-negative subjects, lafutidine was proven to be more effective than famotidine for acid control during the daytime in Japanese healthy volunteers.

Topics: Acetamides; Adult; Aged; Famotidine; Gastric Acid; Gastric Acidity Determination; Gastric Mucosa; Helicobacter pylori; Histamine H2 Antagonists; Humans; Hydrogen-Ion Concentration; Male; Middle Aged; Piperidines; Pyridines; Stomach

To investigate the therapeutic effects of triple therapy combining lafutidine with clarithromycin and amoxicillin on H pylori infection and the resolution of gastroesophageal symptoms after eradication.. We conducted a randomized, multicenter, open-label controlled trial to compare the effectiveness of a triple therapy of lafutidine, clarithromycin, and amoxicillin (lafutidine group) with that of a triple therapy of lansoprazole, clarithromycin, and amoxicillin (lansoprazole group) in patients with H pylori infection. The study group comprised 22 patients with gastric ulcers and 18 patients with duodenal ulcers who had H pylori infection.. H pylori eradication rates were similar in the lafutidine group (14/20, 70%) and the lansoprazole group (14/20, 70%). Gastroesophageal reflux and abdominal symptoms improved after eradication therapy in both groups, whereas abdominal discomfort, diarrhea, and constipation were unchanged. H pylori status had no apparent effect on improvement of gastroesophageal reflux or abdominal symptoms after treatment. Adverse events were similar in both groups.. The triple therapy including lafutidine is equivalent to triple therapy including lansoprazole in terms of H pylori eradication rates and improvement in gastroesophageal reflux and abdominal symptoms. These results are attributed to the fact that lafutidine has strong, continuous antisecretory activity, unaffected by CYP2C19 polymorphisms.

Topics: 2-Pyridinylmethylsulfinylbenzimidazoles; Acetamides; Adult; Aged; Amoxicillin; Anti-Infective Agents; Clarithromycin; Drug Therapy, Combination; Female; Helicobacter Infections; Helicobacter pylori; Histamine H2 Antagonists; Humans; Lansoprazole; Male; Middle Aged; Piperidines; Pyridines

Lafutidine is a novel histamine H(2)-receptor antagonist used primarily as an antisecretory agent in Japan. Previous human studies have not assessed its gastroprotective effects. The purpose of the present study was to determine the effects of lafutidine on the human gastric mucus layer using both histological and biochemical methods.. Of the 14 patients scheduled for gastrectomy who consented to participate, seven were given 14 days of lafutidine 20 mg/day (lafutidine group) and the others received no medication (control group). The surface mucus gel layer in Carnoy-fixed tissue sections was examined immunohistochemically. Both the thickness of the mucus layer and its mucin content were measured in gastric corpus mucosa.. There was no detectable difference between the groups in the grade of gastritis or the immunohistochemical staining characteristics. The laminated structure of the surface mucus gel layer was retained after administration of lafutidine and it was thicker than the layer in the control group. The surface layer in the lafutidine group had three-fold more mucin than that in the control group. There was no difference between the two groups in the mucin content of the deep mucosa.. Lafutidine, given at clinical dosages, not only inhibits acid secretion but also strengthens the mucus barrier of the human gastric mucosa.

Topics: Acetamides; Administration, Oral; Adult; Aged; Anti-Ulcer Agents; Female; Gastric Mucosa; Gastritis; Histamine H2 Antagonists; Humans; Male; Middle Aged; Mucus; Piperidines; Pyridines; Severity of Illness Index; Stomach Neoplasms; Treatment Outcome

Lafutidine, a newly developed histamine H(2)-receptor antagonist, inhibits daytime (i.e., postprandial) as well as nighttime gastric acid secretion in clinical studies. It also has gastroprotective activity that particularly affects mucosal blood flow in rats. This study focused on the efficacy of lafutidine on plasma concentrations of gastrointestinal peptides in humans. Six healthy male volunteers aged 23-32 years without Helicobacter pylori infection were orally administered either 10 mg lafutidine, 20 mg famotidine, or water only (control) 30 min after a standard meal (650 kcal). Plasma concentrations of lafutidine and famotidine were highest from 90 to 150 min after administration. Intragastric pH was elevated after both lafutidine and famotidine compared with the control. Plasma concentrations of calcitonin gene-related peptide (CGRP) and somatostatin were significantly increased after lafutidine at 60 and 90 min. We concluded that lafutidine increases plasma concentrations of CGRP and somatostatin in humans, which may result in inhibition of postprandial acid secretion and gastroprotective activity.

Topics: Acetamides; Administration, Oral; Adult; Biomarkers; Calcitonin Gene-Related Peptide; Cross-Over Studies; Famotidine; Follow-Up Studies; Gastric Acid; Gastric Acidity Determination; Gastric Mucosa; Histamine H2 Antagonists; Humans; Hydrogen-Ion Concentration; Immunoenzyme Techniques; Male; Piperidines; Postprandial Period; Prospective Studies; Pyridines; Reference Values; Somatostatin; Stomach

To examine the effects of the histamine H(2)-receptor antagonist, lafutidine, at clinical dosage (10 mg tablet after a standardized meal) on plasma levels of the gastrointestinal peptides, calcitonin gene-related peptide (CGRP), somatostatin and gastrin.. Six healthy male volunteers ate a standardized meal, and received either lafutidine orally at a dose of 10 mg or water only (control). Blood samples were taken before and up to 4 h after the drug administration. Plasma lafutidine concentrations were determined by high pressure liquid chromatography. Pharmacokinetic analysis of lafutidine was performed using one-compartmental model. The levels of immunoreactive substances of plasma CGRP, somatostatin and gastrin were measured by enzyme immunoassay, and the amount of peptide release was calculated by the trapezoidal method. Lafutidine significantly increased plasma CGRP levels at 1, 1.5, 2.5 and 4 h and the total amount of CGRP release (192 +/- 14.0 pg.h/mL) compared with the control group (128 +/- 21.5 pg.h/mL).. Lafutidine significantly increased the plasma somatostatin levels at 1 and 1.5 h, and the total amount of somatostatin released (107 +/- 18.2 pg.h/mL) compared with the control (78.4 +/- 7.70 pg.h/mL). The area under the drug concentration-time curve (AUC) from 0 to 4 h after administration correlated well with the Delta-CGRP and Delta-somatostatin release but not with total amount of gastrin released. However, plasma gastrin levels were significantly elevated at 1.5 h after drug administration.. Lafutidine at clinical dosage increases plasma CGRP and the somatostatin. The amounts released correlated with the AUC of lafutidine in humans. These results suggest that the increased release of CGRP and somatostatin may contribute to its gastroprotective and anti-acid secretory effect.

Topics: Acetamides; Adult; Area Under Curve; Biological Availability; Calcitonin Gene-Related Peptide; Gastric Mucosa; Gastrins; Half-Life; Histamine H2 Antagonists; Humans; Male; Metabolic Clearance Rate; Piperidines; Pyridines; Somatostatin; Stomach

Improving the quality of ulcer healing (QOUH) is one of the valid methods of prevention of relapse of gastric ulcers. We investigated the effect of lafutidine on the QOUH of gastric ulcer compared with famotidine in a randomized, multi-centre controlled trial. Consecutive 80 patients with a gastric ulcer were randomly assigned to receive twice daily either lafutidine (10 mg) or famotidine (20 mg) for 12 weeks. Esophagogastroduodenoscopy was performed to examine the ulcer healing rate and rate of flat type ulcer scars using dye-contrast. The gastric ulcer healing rate was 92.1% in the lafutidine group (35/38) and 94.7% in the famotidine group (36/38). The rate of flat-type ulcer scars was significantly higher in the lafutidine group (68.4%, 26/38) than in the famotidine group (42.1%, 16/38) (P = 0.021). In conclusion, the present study demonstrated that lafutidine, as compared to famotidine, yields a significantly superior QOUH in patients with gastric ulcers in the clinical setting.

Topics: Acetamides; Adult; Aged; Anti-Ulcer Agents; Drug Administration Schedule; Famotidine; Female; Gastroscopy; Humans; Male; Middle Aged; Piperidines; Pyridines; Stomach Ulcer; Treatment Outcome; Wound Healing

Medication for the relief of heartburn should have the rapid onset of action required for on-demand use. We studied the inhibition of gastric acid secretion by lafutidine and rabeprazole, given in single doses to fasting and postprandial subjects.. A total of 22 healthy male, Helicobacter pylori-negative volunteers participated in this randomized, two-way crossover study. They were randomly assigned to receive a single oral dose of 10 mg lafutidine or 20 mg rabeprazole after fasting overnight (12 subjects, fasting study) or after eating a test meal (noodles, 364 kcal; protein, 10.1 g; fat, 16 g; carbohydrates, 44.9 g; NaCl, 1.1 g; 10 subjects, postprandial study). Intragastric pH was monitored continuously for 6 h after treatment. The other drug was given after a washout period of at least 7 days, and intragastric pH was similarly monitored.. In the fasting study, lafutidine sustained pH at >3 and >4 during the second, third, fourth, fifth, and sixth hours of the study for significantly longer than rabeprazole. During the first 6 h after treatment, lafutidine sustained pH at more than 2, 3, 3.5, 4, 5, 6, and 7 longer than rabeprazole. In the postprandial study, lafutidine sustained pH >3 and >4 for longer periods than rabeprazole during the third, fourth, fifth, and sixth hours of the study. During the first 6 h after treatment, lafutidine sustained pH at more than 2, 3, 3.5, 4, 5, 6, and 7 longer than rabeprazole.. Lafutidine 10 mg produces a prompter rise in intragastric pH than rabeprazole 20 mg in fasting and postprandial Helicobacter pylori-negative male subjects.

Topics: 2-Pyridinylmethylsulfinylbenzimidazoles; Acetamides; Administration, Oral; Adult; Benzimidazoles; Cross-Over Studies; Drug Administration Schedule; Gastric Acid; Gastric Acidity Determination; Heartburn; Humans; Hydrogen-Ion Concentration; Male; Monitoring, Physiologic; Omeprazole; Piperidines; Postprandial Period; Pyridines; Rabeprazole; Reference Values; Risk Assessment; Time Factors; Treatment Outcome

The attenuated anti-secretory activity of H2 receptor antagonists (H2RA) during continuous administration is referred to as the tolerance phenomenon. However, it is not clarified whether Helicobacter pylori infection affects the occurrence of tolerance to H2RA. It is also not clarified whether the tolerance phenomenon occurs to a new H2RA, lafutidine.. To investigate the occurrence of the tolerance phenomenon in subjects with and without H. pylori infection during the continuous administration of lafutidine and famotidine.. Subjects were 20 healthy male volunteers (seven H. pylori positive and 13 H. pylori negative cases). All subjects were examined by ambulatory intragastric pH monitoring five times without medication, on the first and 15th day of the administration of 20 mg b.d. famotidine and 10 mg b.d. lafutidine in a cross-over fashion.. The tolerance phenomenon was not observed in H. pylori-positive subjects during the 15-day-long administration of both H2RAs. In contrast, the tolerance phenomenon was observed in H. pylori negative subjects, which has been previously reported.. This study demonstrated that H. pylori infection affects the tolerance phenomenon during continuous administration of H2RAs.

Topics: Acetamides; Adult; Ambulatory Care; Circadian Rhythm; Cross-Over Studies; Cross-Sectional Studies; Drug Tolerance; Famotidine; Helicobacter Infections; Helicobacter pylori; Histamine H2 Antagonists; Humans; Hydrogen-Ion Concentration; Male; Middle Aged; Piperidines; Pyridines

In contrast to the growing amount of data concerning proton pump inhibitor-based triple therapy for Helicobacter pylori infection, it is still controversial whether proton pump inhibitor can be replaced by H2 receptor antagonist without compromising efficacy. Lafutidine is a novel potent H2 receptor antagonist with gastroprotective activities such as enhancement of gastric mucosal blood flow.. 122 outpatients with positive cultures and subsequent successful cultivation of H. pylori for antimicrobial susceptibility tests were randomized to receive a 7-day course of either lafutidine (20 mg twice daily) or lansoprazole (30 mg twice daily), plus clarithromycin (200 mg twice daily) and amoxicillin (750 mg twice daily). Eradication was considered successful if the rapid urease test, culture, histology and [13]C-urea breath test were all negative at least 4 weeks after cessation of therapy. Cytochrome p450 2C19 genotype status using polymerase chain reaction-restriction fragment length polymorphism was also studied.. On intention-to-treat basis, H. pylori cure was achieved in 52 of 61 (85.2%) patients and 49 of 61 (80.3%) patients for the lafutidine- and lansoprazole-based therapies, respectively. The predicted 95% confidential intervals for the 4.9% of the difference were -1.8-11.6%. Using per protocol analysis, the eradication rates were 88.2% (52/59) and 84.5% (49/58), respectively. The predicted 95% confidential intervals for the 3.7% of the difference were -2.6-10.0%. Adverse events were observed in five and six patients, from the lafutidine and lansoprazole groups, respectively, but they were generally mild. Genetic predisposition of cytochrome p450 2C19 had no significant influence on treatment outcome in both regimens.. The lafutidine-clarithromycin-amoxicillin therapy yielded satisfactory results for eradicating H. pylori, which was comparable with those of the lansoprazole-based regimen with the same drug combination.

Topics: 2-Pyridinylmethylsulfinylbenzimidazoles; Acetamides; Adult; Aged; Amoxicillin; Anti-Bacterial Agents; Anti-Ulcer Agents; Aryl Hydrocarbon Hydroxylases; Clarithromycin; Cytochrome P-450 CYP2C19; Drug Resistance, Bacterial; Drug Therapy, Combination; Female; Helicobacter Infections; Helicobacter pylori; Histamine H2 Antagonists; Humans; Lansoprazole; Male; Middle Aged; Mixed Function Oxygenases; Omeprazole; Penicillins; Piperidines; Prospective Studies; Pyridines

Omeprazole 10 mg is used as maintenance therapy for gastro-oesophageal reflux disease, but previous reports have not mentioned the potency of its acid suppression.. To evaluate the potency of acid suppression with omeprazole 10 mg, in relation to CYP2C19 genotypes.. Eighteen healthy subjects without Helicobacter pylori participated. After a 7-day regimen of omeprazole 10 mg, 20 mg, lafutidine 20 mg (a novel H2-receptor antagonist) or water only (baseline data), intragastric pH was measured for 24 h.. With omeprazole 10 mg, greater differences were observed than 20 mg in median pH values and pH > 4 holding time ratios between poor metabolizers (PMs, n = 6) and the others [homozygous extensive metabolizers (homo-EMs, n = 6) and heterozygous extensive metabolizers (hetero-EMs, n = 6)]. With lafutidine 20 mg, these parameters were not influenced by the genotype. The potency of acid suppression was: omeprazole 20 mg approximately lafutidine 20 mg > omeprazole 10 mg in homo-EMs, omeprazole 20 mg > omeprazole 10 mg approximately lafutidine 20 mg in hetero-EMs, and omeprazole 20 mg approximately omeprazole 10 mg > lafutidine 20 mg in PMs.. Omeprazole 10 mg strongly suppresses acid secretion, but depending on the CYP2C19 genotypes shows greater interindividual variations in suppression than 20 mg.

Topics: Acetamides; Adult; Aryl Hydrocarbon Hydroxylases; Circadian Rhythm; Cross-Over Studies; Cytochrome P-450 CYP2C19; Gastric Acid; Gastric Acidity Determination; Genotype; Humans; Hydrogen-Ion Concentration; Male; Manometry; Mixed Function Oxygenases; Omeprazole; Piperidines; Prospective Studies; Pyridines; Receptors, Histamine H2

Acid aspiration syndrome remains a potentially critical perioperative complication. We compared lafutidine, ranitidine, and rabeprazole for reduction of preoperative gastric fluid acidity and volume in elective surgery and found that these variables were minimized with a single morning dose of lafutidine 20 mg compared with ranitidine or rabeprazole. Preoperative oral lafutidine may be an alternative to ranitidine as a prophylaxis against aspiration pneumonia.

Topics: 2-Pyridinylmethylsulfinylbenzimidazoles; Acetamides; Adult; Aged; Anti-Ulcer Agents; Benzimidazoles; Enzyme Inhibitors; Female; Gastric Acid; Gastric Acidity Determination; Histamine H2 Antagonists; Humans; Intraoperative Complications; Intubation, Gastrointestinal; Male; Middle Aged; Omeprazole; Piperidines; Preoperative Care; Proton Pump Inhibitors; Pyridines; Rabeprazole; Ranitidine; Risk Assessment; Stomach

This study evaluated the utility of the histamine H2-receptor antagonist lafutidine in patients taking oral fluorouracil (S-1) for head and neck squamous cell carcinoma (HNSCC), by comparing patients with and without concomitant lafutidine.. Study subjects comprised 63 patients who received adjuvant S-1 following curative resection of HNSCC at our institutions between August 1, 2013 and December 31, 2019. The primary endpoint was the completion rate of S-1 therapy.. For the lafutidine-treated group, the median completion rate was significantly greater (94.4% vs. 24.6%, p=0.01), and progression-free and overall survival were both significantly prolonged compared to the non-lafutidine group. In terms of adverse events, the incidence of diarrhoea was significantly reduced (p<0.00189) in the lafutidine-treated group.. Taking lafutidine during S-1 treatment appeared to reduce gastrointestinal disturbance and increased the S-1 completion rate, improving both progression-free and overall survival as a result.

Topics: Acetamides; Adult; Aged; Antimetabolites, Antineoplastic; Drug Combinations; Female; Head and Neck Neoplasms; Histamine H2 Antagonists; Humans; Male; Middle Aged; Oxonic Acid; Piperidines; Pyridines; Retrospective Studies; Tegafur

Amongst assorted regio-selective and targeted oral drug delivery strategies accepted for the gastro-retentive drug delivery system (GRDDS), the floating drug delivery system (FDDS) holds a major share as clinically accepted formulations. The major objective of the present investigation was to explore the silk industry waste protein, silk fibroin (SF) as a possible electrospun nanocarrier for the FDDS. In a nutshell, electrospinning (ES) is one of the flexible and astonishing strategies for the fabrication of porous electrospun nanofibers (NFs), which offers the potential to amend the floating profile, dissolution rate, solubility, and release patterns of the drug, etc as per compendial requirements. Looking at the prospects of floating SF-NFs preparation, we have isolated and lyophilized the SF from industrial waste cocoons and prepared drug-loaded SF single polymer nanofibers (SPN). Lafutidine (LF) being a good candidate for GRDDS selected as a model drug, which is an excellent proton pump inhibitor, mainly used in the treatment of gastric ulcers. Finally, the obtained LF loaded SF-NFs (LF-SF-NFs) were successfully analyzed for physicochemical characteristics, porosity, swelling index, antioxidant activity, mucoadhesion strength, floating properties, enzymatic degradation, and accelerated stability study, etc. Further, these LF-SF-NFs were evaluated for percent drug content, weight variation, in-vitro dissolution in 0.1 N hydrochloric acid (HCl, pH:1.2) and fasted state simulated gastric fluid (FSSGF), and accelerated stability study. It has shown significant floating time >18 h, about 99% ± 0.58% floating buoyancy with sustained release up to 24 h. LF-SF-NFs showed good compatibility, entrapment efficiency, antioxidant activity, mucoadhesion strength, enzymatic degradation, and long term stability. Soon, the essential floating and drug release profiles can claim single polymer (SF) based electrospun protein NFs as a possible novel oral nanocarrier for FDDS.

Topics: Acetamides; Animals; Anti-Ulcer Agents; Bombyx; Drug Carriers; Drug Delivery Systems; Drug Liberation; Fibroins; Goats; Intestinal Mucosa; Nanofibers; Piperidines; Pyridines

The objective of the present study was to evaluate the effect of mulberry leaf extract (ME) fermented with Lactobacillus acidophilus A4 (A4) on intestinal mucositis induced by 5-fluorouracil (5-FU) in a rat model. Male Wistar rats were gavaged with A4, ME, fermented mulberry leaf extract FME) or lafutidine (LAF) for 10 days and injected intraperitoneally with 5-FU (150 mg kg. Our results suggest that fermented mulberry leaf extract (ME) may provide synergistic therapeutic benefits of both probiotics and natural plant extracts in prevention of 5-fluorouracil-induced mucositis. These impacts are particularly significant given the induction of MUC2 and MUC5AC gene expressions for production of mucins and the reduction of pro-inflammatory cytokine interleukin-1β in gut environments. Therefore, we proposed that enhanced functionality of ME by fermentation of Lactobacillus acidophilus A4 can be applied as food-grade adjuncts for mucositis therapy and prevention in food industry.

Topics: Acetamides; Animals; Cytokines; Disease Models, Animal; Fermentation; Fluorouracil; Intestinal Mucosa; Intestines; Lactobacillus acidophilus; Male; Morus; Mucositis; Piperidines; Plant Leaves; Probiotics; Pyridines; Rats; Rats, Wistar

Intestinal mucositis accompanied by severe diarrhea is one of the most common side effects during cancer chemotherapy. Lafutidine, a histamine H2 receptor antagonist with mucosal protective properties via sensory afferent neurons, is used for the treatment of upper gastrointestinal diseases. The present study investigated the effects of lafutidine on 5-fluorouracil (5-FU)-induced intestinal mucositis induced in mice. Male C57BL/6 wild-type (WT), sensory deafferented mice, and transient receptor potential vanilloid subfamily 1 knockout (TRPV1KO) mice were used. Animals were administered 5-FU once daily, while lafutidine and famotidine were administered twice daily for 6 days. Repeated administration of 5-FU caused severe intestinal mucositis, characterized by shortening of villi and destruction of crypts and was accompanied by diarrhea and body weight loss. Daily administration of lafutidine reduced the severity of intestinal mucositis, diarrhea and body weight loss in a dose-dependent manner, while famotidine had no effect on intestinal mucositis. The preventive effects of lafutidine were completely abolished in sensory deafferented and TRPV1-KO mice. Lafutidine significantly suppressed 5-FU-increased MPO activity and inflammatory cytokine expression on day 6, but not apoptosis induction in intestinal crypts on day 1. Lafutidine induced Alcian Blue and PAS-positive mucus production in the small intestine. These findings suggest that lafutidine attenuates 5-FU-induced intestinal mucositis, most likely by increasing mucus production via activation of sensory afferent neurons. Furthermore, intact TRPV1 signaling is essential for the activation of sensory afferent neurons induced by lafutidine. Therefore, lafutidine is more useful than other common antacids for the treatment of intestinal mucositis during cancer chemotherapy.

Topics: Acetamides; Animals; Antimetabolites, Antineoplastic; Diarrhea; Famotidine; Fluorouracil; Histamine H2 Antagonists; Interleukin-1beta; Intestinal Mucosa; Intestines; Male; Mice, Inbred C57BL; Mice, Knockout; Mucositis; Peroxidase; Piperidines; Pyridines; RNA, Messenger; Tumor Necrosis Factor-alpha

The interactions between lafutidine (LAF) and calf thymus DNA (ctDNA) have been investigated both experimentally and theoretically. UV-vis absorption studies confirmed that LAF binds to ctDNA through non-covalent interactions. Fluorescence quenching and time-resolved fluorescence spectroscopy studies showed that the binding of LAF with ctDNA occurred through static quenching mechanism, resulting in the formation of a LAF-ctDNA complex. The binding constants (K) of the complex were found to be around 10

Topics: Acetamides; Animals; Antineoplastic Agents; Cattle; DNA; Magnetic Resonance Spectroscopy; Molecular Docking Simulation; Molecular Dynamics Simulation; Nucleic Acid Conformation; Piperidines; Pyridines; Thermodynamics

The aim of this study was to evaluate the pharmacokinetics (PK) of single and multiple doses of oral lafutidine tablets and the effect of food on the PK properties in healthy Chinese subjects. The tolerability and the effect of gender on the PK properties were also evaluated to acquire more PK information.. Three PK studies were conducted in 12 healthy Chinese subjects (6 male, 6 female). Study 1 was a single-dose, three-period, three-dose level (10, 20, and 40 mg), three-sequence cross-over study under fasting conditions. Study 2 was a repeat-dose study (10 mg twice daily over 6 days; all 12 subjects). Study 3 was a two-period, two-sequence cross-over single-dose (10 mg) food interaction study. All randomizations (study 1, study 3) were done to ascertain 1:1 gender ratio per sequence. A validated liquid chromatography tandem mass spectrometry (LC/MS/MS) method was used to determine plasma lafutidine concentrations. PK parameters were calculated by the non-compartmental method.. The area under the time-concentration curve (AUC) and maximum plasma concentration (C. The PK of lafutidine showed dose proportionality. There was no significant accumulation of lafutidine tablets with multiple dosing. Food did not affect the degree of lafutidine absorption, but it did reduce the rate of absorption. Further study is needed regarding the effect of gender on lafutidine. Lafutidine was well tolerated within the dose range 10-40 mg, and no serious adverse events were observed.

Topics: Acetamides; Administration, Oral; Adult; Anti-Ulcer Agents; Area Under Curve; Asian People; Cross-Over Studies; Dose-Response Relationship, Drug; Drug Monitoring; Female; Food-Drug Interactions; Healthy Volunteers; Humans; Male; Piperidines; Pyridines; Stomach Ulcer; Tablets; Tandem Mass Spectrometry

In this study, lafutidine (LAF) was used as a model compound to investigate the binding mechanism between antiulcer drugs and human serum albumin (HSA) through various techniques, including STD-NMR, WaterLOGSY-NMR, (1)H NMR relaxation times, tr-NOESY, molecule docking calculation, FT-IR spectroscopy, and CD spectroscopy. The analyses of STD-NMR, which derived relative STD (%) intensities, and WaterLOGSY-NMR, determined that LAF bound to HSA. In particular, the pyridyl group of LAF was in close contact with HSA binding pocket, whereas furyl group had a secondary binding. Competitive STD-NMR and WaterLOGSY-NMR experiments, with warifarin and ibuprofen as site-selective probes, indicated that LAF preferentially bound to site II in the hydrophobic subdomains IIIA of HSA. The bound conformation of LAF at the HSA binding site was further elucidated by transferred NOE effect (tr-NOESY) experiment. Relaxation experiments provided quantitative information about the relationship between the affinity and structure of LAF. The molecule docking simulations conducted with AutoDock and the restraints derived from STD results led to three-dimensional models that were consistent with the NMR spectroscopic data. The presence of hydrophobic forces and hydrogen interactions was also determined. Additionally, FT-IR and CD spectroscopies showed that LAF induced secondary structure changes of HSA.

Topics: Acetamides; Binding Sites; Circular Dichroism; Humans; Magnetic Resonance Spectroscopy; Molecular Docking Simulation; Piperidines; Protein Binding; Protein Domains; Protein Structure, Secondary; Protons; Pyridines; Serum Albumin; Spectrophotometry; Spectroscopy, Fourier Transform Infrared; Stomach Ulcer; Warfarin

Lafutidine a newly developed histamine H2-receptor antagonist having biological half-life of 1.92 ± 0.94 h due to its selective absorption from upper part of gastrointestinal tract the development of mucoadhesive sustained release drug delivery system is recommended in order to enhance the bioavailability. A mucoadhesive tablets was developed using the natural polymer, sodium alginate, xanthan gum and karaya gum. Mucoadhesion is a complex phenomenon which involves wetting, adsorption and interpenetration of polymer chains. The prepared tablets of various formulations were evaluated for a total mucoadhesion time, buoyancy lag time and percentage drug released. The formulation with xanthan gum showed better results. Thus, it may be useful for prolonged drug release in stomach to improve the bioavailability and reduced dosing frequency. Non-fickians release transport was confirmed as the drug release mechanism from the optimized formulation by Korsmeyer-Peppas. The optimized formulation (B3) showed a mucoadhesive strength >35 g. In vivo study was performed using rabbits by X-ray imaging technique. Radiological evidences suggest that, a formulated tablet was well adhered for >10 h in rabbit's stomach. Optimized lafutidine mucoadhesive tablets showed no significant change in physical appearance, drug content, mucoadhesive properties and in vitro dissolution pattern after storage at 40 °C temperature 75 ± 5% relative humidity for 3 months.

Topics: Acetamides; Adhesiveness; Alginates; Animals; Biological Availability; Delayed-Action Preparations; Drug Compounding; Drug Liberation; Gastric Mucosa; Glucuronic Acid; Hexuronic Acids; Histamine H2 Antagonists; In Vitro Techniques; Karaya Gum; Piperidines; Polysaccharides, Bacterial; Pyridines; Rabbits; Spectroscopy, Fourier Transform Infrared; Swine; Tablets; Tissue Adhesives

We conducted a retrospective cohort study evaluating the efficacy and usefulness of the addition of lafutidine, a novel histamine H2-receptor antagonist, in treatment of patients with idiopathic chronic urticaria whose disease was not well controlled with histamine H1-receptor antagonists. Based on the assessment of global improvement, moderate or better improvement was achieved in 39 of 46 patients (85%) after 1-3 weeks of additional administration of lafutidine and 35 patients (76%) after 3 months. No incidence of drug-related adverse reactions was reported in any patient. Lafutidine was rated as useful or better in 34 patients (74%) after 3 months of treatment. The usefulness of the drug was not affected by differences in background factors, such as disease duration, previous treatment duration and the number of concomitant H1-receptor antagonists. Lafutidine appears to be a promising addition to histamine H1-receptor antagonist therapy for the treatment of chronic urticaria resistant to treatment with H1-receptor antagonists alone.

Topics: Acetamides; Adolescent; Adult; Aged; Chronic Disease; Drug Therapy, Combination; Female; Histamine H1 Antagonists; Histamine H2 Antagonists; Humans; Male; Middle Aged; Piperidines; Pyridines; Retrospective Studies; Urticaria; Young Adult

Gastrointestinal mucositis is a frequent complication of antineoplastic chemotherapy, but the effects of chemotherapy on mucosal defense mechanisms remain poorly understood. We studied the effects of cisplatin on mucin, one of the principal defense factors of the gastrointestinal mucosa, and evaluated the efficacy of two different types of H2-receptor antagonists against cisplatin-induced mucositis.. Cisplatin (6 mg/kg) was administered intravenously to rats (day 0). The rats were sacrificed 1, 3, 7, and 11 days after treatment, and their stomach, jejunum, ileum, and colon were removed. Immunoreactivity of the mucosa was compared with the use of anti-mucin monoclonal antibody. To evaluate the efficacy of H2-receptor antagonists, either famotidine (3 mg/kg) or lafutidine (30 mg/kg) was given orally once daily on days 0, 1, and 2. Histological and biochemical findings were compared among the groups to assess effects on cisplatin-induced injury.. Cisplatin significantly altered the immunoreactivity and content of mucin in the small intestinal mucosa, especially in the ileum. Lafutidine protected against cisplatin-induced mucosal injury and attenuated decreased mucin accumulation.. Cisplatin appears to alter the mucus barrier function in the intestinal mucosa. Lafutidine might effectively prevent chemotherapy-induced mucositis by activating intestinal mucus cells.

Topics: Acetamides; Animals; Cisplatin; Humans; Intestinal Mucosa; Mucositis; Piperidines; Pyridines; Rats

A previous report showed that histamine in denuded mesenteric vascular beds produced a triphasic response; an initial small histamine H(2) receptor-mediated vasodilation, a transient histamine H(1) receptor-mediated vasoconstriction, and finally a long-lasting vasodilation. We further investigated the vascular effect of histamine in mesenteric preparations without an endothelium to clarify the possible involvement of perivascular nerves. Male Wistar rat mesenteric vascular beds without an endothelium were perfused with Krebs solution containing methoxamine to produce active tone and lafutidine to block histamine H(2) receptor-mediated vasodilation. Histamine (1-100μM) was perfused for 1min and perfusion pressure was measured with a pressure transducer. Histamine caused a biphasic vascular response; initial vasoconstriction followed vasodilation. Tetrodotoxin (a neurotoxin, 1μM) and procaine (a local anesthetic, 100μM) significantly inhibited the vasoconstriction and vasodilation. Ruthenium red (a transient receptor potential vanilloid 1 (TRPV1) antagonist, 1μM) also significantly inhibited both phases of the response. Pretreatment with capsaicin (a depletor of calcitonin gene-related peptide (CGRP)-containing nerves, 5μM) significantly inhibited the vasodilation without affecting the initial vasoconstriction. Both indomethacin (a cyclooxygenase inhibitor, 0.5μM) and seratrodast (a thromboxane A(2) receptor antagonist, 0.1μM) abolished the histamine-induced vasoconstriction and subsequent vasodilation. These results suggest that histamine-induced vasoconstriction and long-lasting vasodilation are mediated by activation of TRPV1 on capsaicin-sensitive and capsaicin-insensitive nerves. They also suggest that perivascular nerves and prostanoids, probably thromboxane A(2), are responsible for the vascular response to histamine.

Topics: Acetamides; Animals; Benzoquinones; Capsaicin; Endothelium, Vascular; Heptanoic Acids; Histamine; Indomethacin; Male; Mesenteric Arteries; Methoxamine; Piperidines; Procaine; Prostaglandins; Pyridines; Rats; Rats, Wistar; Receptors, Histamine H2; Ruthenium Red; Tetrodotoxin; Thromboxane A2; TRPV Cation Channels; Vasoconstriction; Vasodilation

Topics: 2-Pyridinylmethylsulfinylbenzimidazoles; Acetamides; Anti-Ulcer Agents; Central Nervous System Diseases; Clopidogrel; Histamine H2 Antagonists; Humans; Middle Aged; Piperidines; Pyridines; Rabeprazole; Stomach Ulcer; Ticlopidine

Gastroesophageal reflux disease is considered to be caused primarily by gastric juice refluxed into the esophagus. Here, we investigated the possible involvement of host defense mechanisms in the development of acute reflux esophagitis using lafutidine, a histamine H(2) receptor antagonist (H(2)RA) with proven gastric mucosal protective effects.. The ligation of both the pylorus and the forestomach of SD rats under anesthesia caused hemorrhagic lesions in the esophageal mucosa at 6 h. Lesion formation was significantly inhibited by treatment with H(2)RAs, including the conventional H(2)RAs famotidine and cimetidine as well as lafutidine. The maximum suppressive abilities of these agents were similar to that of the proton pump inhibitor lansoprazole. Interestingly, unlike famotidine, lafutidine at low doses significantly suppressed esophagitis without inhibiting gastric acid secretion. Note that neither lafutidine nor famotidine inhibited hexosamine output in gastric juice samples obtained 3 h after ligation. Additionally, the protective effect of lafutidine, but not of famotidine, was partly attenuated by the denervation of capsaicin-sensitive afferent nerves with a large dose of capsaicin.. The present results indicate that esophageal host-defense via capsaicin-sensitive afferent nerves may contribute to the therapeutic action of lafutidine.

Topics: Acetamides; Acute Disease; Animals; Dose-Response Relationship, Drug; Esophagitis, Peptic; Esophagus; Histamine H2 Antagonists; Male; Neurons, Afferent; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley

Gastric acid secretion during the daytime has been implicated in the pathogenesis of acid-related diseases. Although daytime acid secretion is mainly governed by the parasympathetic vagal nerve, clinical observations have been accumulated that the H(2)-receptor antagonist lafutidine may have a strong effect. Here, we examined the actions of H(2)-receptor antagonists in a rat model of gastric acid secretion induced by stomach distention, a major post-meal stimulus. Indeed, the acid output during a 3h period after the instillation of saline into pylorus-ligated SD rats under urethane anesthesia was dependent on the instilled volume and was strongly suppressed by a vagotomy or the intraduodenal administration of atropine. Interestingly, lafutidine, but not famotidine or cimetidine, administered at a sufficient dose to block histamine-dependent acid secretion was capable of inhibiting distention-induced acid secretion. Moreover, gastric acid secretion induced by the intravenous perfusion of carbachol into SD rats was strongly inhibited by lafutidine but only partially inhibited by famotidine. The antisecretory action of lafutidine under these conditions was partly reversed by the co-administration of the nitric oxide synthase inhibitor L-NMMA, but was hardly affected by denervation with capsaicin or by the administration of the transient receptor potential channel V1 (TRPV1) antagonist capsazepine. Together with the observation that lafutidine increased the amount of intragastric nitric oxide, the present results suggest that lafutidine inhibits daytime gastric acid secretion not only by blocking H(2) receptors, but also through nitric oxide-mediated and histamine-independent indirect actions.

Topics: Acetamides; Animals; Gastric Acid; Gastric Mucosa; Histamine H2 Antagonists; Male; Nitric Oxide; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley; Receptors, Histamine H2; Stomach

Steroids and H(2) blockers are commonly used as supportive care for taxane-containing chemotherapy, but they also affect docetaxel's primary metabolizer, cytochrome P(450) 3A4. This retrospective observational study was performed to better understand the effects of these compounds on docetaxel-induced skin toxicities, specifically hand-foot syndrome (HFS) and facial erythema (FE), a relationship that is currently poorly understood. Member institutions of the Japan Breast Cancer Research Group were invited to complete a questionnaire on the occurrence of grade 2 or higher HFS and FE among patients treated between April 2007 and March 2008 with docetaxel as an adjuvant or neoadjuvant chemotherapeutic treatment for breast cancer. We obtained data for 993 patients from 20 institutions. Twenty percent received H(2) blockers, and all patients received dexamethasone. Univariate and multivariate analyses revealed that H(2) blockers are associated with a significantly higher incidence of both HFS and FE. The incidence of FE was significantly higher for the docetaxel + cyclophosphamide (TC) regimen than for non-TC regimens combined. Dexamethasone usage did not affect the incidence of either HFS or FE. In conclusion, use of H(2) blockers as premedication in breast cancer patients receiving docetaxel significantly increases the risk of both HFS and FE.

Topics: Acetamides; Breast Neoplasms; Chemotherapy, Adjuvant; Dexamethasone; Docetaxel; Erythema; Famotidine; Female; Glucocorticoids; Hand-Foot Syndrome; Histamine H2 Antagonists; Humans; Incidence; Logistic Models; Multivariate Analysis; Neoadjuvant Therapy; Piperidines; Pyridines; Ranitidine; Retrospective Studies; Steroids; Surveys and Questionnaires; Taxoids

We examined the effect of lafutidine, a histamine H(2) receptor antagonist with a mucosal protective action mediated by capsaicin-sensitive sensory neurons (CSN), on intestinal lesions produced by loxoprofen administration in rats.. Animals were given loxoprofen (10-100 mg/kg p.o.) and killed 24 h later. Lafutidine (10 and 30 mg/kg), cimetidine (100 mg/kg) or famotidine (30 mg/kg) was given twice p.o. at 0.5 h before and 6 h after loxoprofen. Omeprazole (100 mg/kg) was given p.o. once 0.5 h before. Ampicillin (800 mg/kg) was given p.o. twice at 24 h and 0.5 h before loxoprofen, while 16,16-dimethyl prostaglandin E(2) (dmPGE(2); 0.01 mg/kg) was given i.v. twice at 5 min before and 6 h after.. Loxoprofen dose-dependently produced hemorrhagic lesions in the small intestine, accompanied by invasion of enterobacteria and increased inducible nitric oxide synthase (iNOS) expression as well as myeloperoxidase activity in the mucosa. The ulcerogenic response to loxoprofen (60 mg/kg) was significantly prevented by lafutidine (30 mg/kg), similar to dmPGE(2) and ampicillin, and the effect of lafutidine was totally attenuated by ablation of CSN. Neither cimetidine, famotidine nor omeprazole had a significant effect against these lesions. Lafutidine alone increased mucus secretion and reverted the decreased mucus response to loxoprofen, resulting in suppression of bacterial invasion and iNOS expression. In addition, loxoprofen downregulated Muc2 expression, and this response was totally reversed by lafutidine mediated by CSN.. Lafutidine protects the small intestine against loxoprofen-induced lesions, essentially mediated by the CSN, and this effect may be functionally associated with increased Muc2 expression/mucus secretion, an important factor in the suppression of bacterial invasion.

Topics: 16,16-Dimethylprostaglandin E2; Acetamides; Ampicillin; Animals; Anti-Bacterial Agents; Anti-Ulcer Agents; Capsaicin; Cimetidine; Disease Models, Animal; Enterobacteriaceae; Famotidine; Histamine H2 Antagonists; Intestinal Mucosa; Intestine, Small; Male; Mucin-2; Nitric Oxide Synthase Type II; Omeprazole; Peptic Ulcer; Peroxidase; Phenylpropionates; Piperidines; Proton Pump Inhibitors; Pyridines; Rats; Rats, Sprague-Dawley; RNA, Messenger; Sensory Receptor Cells

It is still controversial which drugs, proton pump inhibitors (PPI) or histamine-2 receptor antagonists (H2RA), are more effective for dyspepsia in the Japanese population.. Patients with uninvestigated dyspepsia (n = 104; male/female 41/63) were treated with either rabeprazole 10 mg o.d. (n = 62) or lafutidine 10 mg b.i.d. (n = 42) for 4 weeks. Questionnaires (modified Frequency Scale for the Symptoms of Gastroesophageal Reflux Disease [mFSSG] and quality of life [QOL], SF-8) were administered before and after therapy. The mFSSG was classified into a total score (Q-T), reflux score (Q-R), dyspepsia score (Q-D) and pain score (Q-P). The SF-8 had a physical component summary (PCS) and mental component summary (MCS). The predominant type of symptom was reflux (R-S), pain (P-S) or dysmotility (D-S).. R-S was 19.2%, P-S 48.1%, D-S 24.0% and overlap 8.7%. In the R-S, Q-T and Q-R significantly improved with rabeprazole, but neither scale improved with lafutidine. MCS significantly improved with rabeprazole. In P-S, Q-T, Q-R, Q-D and Q-P significantly improved with both drugs. PCS significantly improved with both, whereas the MCS significant improved with rabeprazole. In D-S, Q-R and Q-D significant improved with rabeprazole, but neither improved with lafutidine. QOL did not improve with either. With overlap, neither scale nor the QOL reached a significant difference.. Both PPI and H2RA have a positive effect on P-S, but H(2)RA therapy is limited for R-S and D-S, whereas PPI therapy is generally effective. Therefore, careful prescription based on symptoms is important.

Topics: 2-Pyridinylmethylsulfinylbenzimidazoles; Acetamides; Adult; Dyspepsia; Esophageal Motility Disorders; Female; Gastroesophageal Reflux; Histamine H2 Antagonists; Humans; Japan; Male; Middle Aged; Pain; Pain Measurement; Piperidines; Proton Pump Inhibitors; Pyridines; Rabeprazole; Retrospective Studies; Severity of Illness Index; Surveys and Questionnaires; Treatment Outcome

Luminal acid or CO₂ induces a hyperemic response in the esophagus, via activation of acid sensors on capsaicin-sensitive afferent nerves (CSAN). Since disruption of the hyperemic response to luminal CO₂ acidifies the interstitium of the esophageal mucosa, the hyperemic response may maintain interstitial pH (pH(int)). We hypothesized that acid-related hyperemia maintains pH(int), preventing acid-induced injury in the esophageal mucosa.. We examined the effects of capsaicin (Cap) or lafutidine (Laf), a mucosal protective H₂ antagonist, on the regulation of pH(int) and blood flow in rat esophagus using ratiometric microimaging and laser-Doppler measurements of the lower esophageal mucosa of living rats. The esophagus was topically superfused with pH 7.0 buffer, or a pH 1.0 or pH 1.0 + pepsin (1 mg/ml) solution with or without Laf.. Cap (30 or 100 µM) or Laf (0.1 or 1 mM) dose-dependently increased blood flow, accompanied by increased pH(int). The pH 1.0 solution increased blood flow without pH(int) change, whereas Laf (1 mM) increased blood flow and pH(int) during acid exposure. The effects of Laf were abolished by ablation of CSAN. Perfusion of the acidified pepsin solution gradually decreased pH(int), inhibited by Laf perfusion.. Activation of CSAN by Laf with or without acid, accompanied by hyperemia, increased pH(int), preventing acidified pepsin-induced interstitial acidification. Stimulation of the capsaicin pathway with compounds such as Laf enhances mucosal protection from acid-related injury in the upper gastrointestinal tract.

Topics: Acetamides; Animals; Capsaicin; Esophagus; Histamine H2 Antagonists; Laser-Doppler Flowmetry; Male; Mucous Membrane; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley; Regional Blood Flow

We investigated the influence of 5-fluorouracil (5-FU), an anti-tumor agent, on the healing of gastric lesions generated by 0.6 M HCl in rats and the effect of lafutidine, a histamine H(2) receptor antagonist, on the impaired healing. Animals fasted for 18 h were given 1 ml of 0.6 M HCl p.o., fed normally from 1 h later, and killed 1-96 h thereafter. 5-FU was given i.v. twice, 1 h and 24 h after the HCl. The gastric lesions healed spontaneously within 96 h. Although it decreased acid secretion, 5-FU markedly delayed the healing. Lafutidine, but not cimetidine, given p.o. immediately after each dosing of 5-FU significantly reversed the delay in healing by 5-FU, and this effect was attenuated by the chemical ablation of capsaicin-sensitive afferent neurons. Capsaicin also significantly reversed the delay in healing. The mucosal application of 50 mM HCl did not affect gastric mucosal blood flow (GMBF) in the normal stomach, but significantly increased it in the stomach damaged by 0.6 M HCl. The increases in GMBF were attenuated by 5-FU; however, the co-administration of lafutidine significantly restored the response. In addition, 5-FU inhibited both cell proliferation and migration in rat gastric epithelial cells (RGM1) in vitro. These results suggest that 5-FU delayed the healing of gastric lesions generated by 0.6 M HCl, probably through the inhibition of cell migration and proliferation, as well as the impairment of GMBF, and lafutidine reversed the delay in healing, mainly through the amelioration of the GMBF response mediated by capsaicin-sensitive afferent neurons.

Topics: Acetamides; Animals; Antimetabolites, Antineoplastic; Capsaicin; Cell Line; Cell Movement; Cell Proliferation; Disease Models, Animal; Epithelial Cells; Fluorouracil; Gastric Mucosa; Histamine H2 Antagonists; Hydrochloric Acid; Male; Neurons, Afferent; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley; Regional Blood Flow; Sensory System Agents; Stomach Diseases; Wound Healing

Lafutidine is a histamine H2 receptor antagonist, the gastroprotective effect of which is related to its antisecretory activity and its ability to activate a sensory neuron-dependent mechanism of defence. The present study investigated whether intragastric administration of lafutidine (10 and 30 mg/kg) modifies vagal afferent signalling, mucosal injury, intragastric acidity and gastric emptying after gastric acid challenge.. Adult rats were treated with vehicle, lafutidine (10 - 30 mg/kg) or cimetidine (10 mg/kg), and 30 min later their stomachs were exposed to exogenous HCl (0.25 M). During the period of 2 h post-HCl, intragastric pH, gastric volume, gastric acidity and extent of macroscopic gastric mucosal injury were determined and the activation of neurons in the brainstem was visualized by c-Fos immunocytochemistry.. Gastric acid challenge enhanced the expression of c-Fos in the nucleus tractus solitarii but caused only minimal damage to the gastric mucosa. Lafutidine reduced the HCl-evoked expression of c-Fos in the NTS and elevated the intragastric pH following intragastric administration of excess HCl. Further analysis showed that the gastroprotective effect of lafutidine against excess acid was delayed and went in parallel with facilitation of gastric emptying, measured indirectly via gastric volume changes, and a reduction of gastric acidity. The H2 receptor antagonist cimetidine had similar but weaker effects.. These observations indicate that lafutidine inhibits the vagal afferent signalling of a gastric acid insult, which may reflect an inhibitory action on acid-induced gastric pain. The ability of lafutidine to decrease intragastric acidity following exposure to excess HCl cannot be explained by its antisecretory activity but appears to reflect dilution and/or emptying of the acid load into the duodenum. This profile of actions emphasizes the notion that H2 receptor antagonists can protect the gastric mucosa from acid injury independently of their ability to suppress gastric acid secretion.

Topics: Acetamides; Animals; Cimetidine; Female; Gastric Acid; Gastric Emptying; Gastric Mucosa; Histamine H2 Antagonists; Hydrochloric Acid; Hydrogen-Ion Concentration; Models, Animal; Neurons, Afferent; Piperidines; Proto-Oncogene Proteins c-fos; Pyridines; Rats; Rats, Sprague-Dawley; Signal Transduction; Solitary Nucleus; Stomach; Time Factors

We report a 75-year-old female gastric cancer patient with paclitaxel-induced peripheral neuropathy, which was successfully treated by the H2-blocker, lafutidine. From December 2007, she underwent second-line chemotherapy using paclitaxel (80 mg/m/2 day 1, 7, 14/28 days) for peritoneal dissemination which had been refractory to first-line chemotherapy using S-1 (80 mg/m / 2, day 1-28/42 days). After 2 courses, CT showed a complete response (CR) of the peritoneal dissemination. However, at the same time peripheral neuropathy appeared, which was aggravated to grade 3 at the 6th course. Beginning with the 7th course, we administered lafutidine (10 mg/day) for peripheral neuropathy, which recovered to grade 1 after 14 days of lafutidine administration. Lafutidine was administered until July 2008, when peripheral neuropathy kept grade 1 without lafutidine. After 9 courses, paclitaxel therapy failed because of general fatigue.

Topics: Acetamides; Aged; Antineoplastic Agents, Phytogenic; Female; Histamine H2 Antagonists; Humans; Paclitaxel; Peripheral Nervous System Diseases; Piperidines; Pyridines; Stomach Neoplasms

A sensitive and universal LC-MS/MS method for the simultaneous determination of famotidine, cimetidine, ranitidine and lafutidine in human plasma was presented. This is the first single LC-MS/MS method reported for the simultaneous analysis of these four H(2) antagonists in human plasma. Following liquid-liquid extraction with ethyl acetate, the separation was performed on an Agilent Zorbax SB-CN (150 mm x 2.1mm I.D., 5 microm) column using a mobile phase consisted of methanol:20 mM ammonium acetate (55:45, v/v). The total run time was 7 min per sample. Quantification was performed by electrospray ionization-triple quadrupole mass spectrometry by selected reaction monitoring (SRM) detection in the positive mode. All calibration curves showed good linear regression (r(2)>0.99) from 0.5 to 1000 ng/mL for famotidine and lafutidine, and 5-20,000 ng/mL for cimetidine and ranitidine. The method showed good precision and accuracy with overall intra- and inter-day variations of 1.37-9.29% and 3.51-9.40%, respectively. The assay was successfully applied to a bioequivalence study using ranitidine as the model compound.

Topics: Acetamides; Calibration; Chromatography, Liquid; Cimetidine; Famotidine; Histamine H2 Antagonists; Humans; Piperidines; Pyridines; Ranitidine; Reproducibility of Results; Tandem Mass Spectrometry; Therapeutic Equivalency

We described 3 cases of stomatitis caused by chemotherapy with the fluoropyrimidine preparation S-1, alone or combined with other anticancer drugs. The stomatitis did not respond to conventional oral mucosal treatment such as triamcinolone acetonide(Kenalog)or allopurinol, but improved after treatment with the histamine H2-receptor antagonist lafutidine. The concurrent use of lafutidine allowed these 3 patients to continue chemotherapy with no recurrence of stomatitis. We concluded that lafutidine may be a viable treatment option for chemotherapy-induced stomatitis, allowing treatment to be continued.

Topics: Acetamides; Aged; Antineoplastic Combined Chemotherapy Protocols; Gastrointestinal Neoplasms; Humans; Male; Middle Aged; Piperidines; Pyridines; Stomatitis

Lafutidine is a histamine H(2)-receptor antagonist with gastric antisecretory and gastroprotective activity associated with activation of capsaicin-sensitive nerves. The present study examined the effect of lafutidine on neurotransmission of capsaicin-sensitive calcitonin gene-related peptide (CGRP)-containing vasodilator nerves (CGRPergic nerves) in rat mesenteric resistance arteries. Rat mesenteric vascular beds were perfused with Krebs solution and vascular endothelium was removed by 30-s perfusion with sodium deoxycholate. In preparations preconstricted by continuous perfusion of methoxamine (alpha(1) adrenoceptor agonist), perfusion of lafutidine (0.1 - 10 microM) concentration-dependently augmented vasodilation induced by the periarterial nerve stimulation (PNS, 1 Hz) without affecting vasodilation induced by exogenous CGRP (10 pmol) injection. Perfusion of famotidine (H(2)-receptor antagonist, 1 - 100 microM) had no effect on either PNS-induced or CGRP-induced vasodilation. Perfusion of lafutidine concentration-dependently augmented vasodilation induced by a bolus injection of capsaicin (vanilloid-1 receptor agonist, 30 pmol). The presence of a vanilloid-1 receptor antagonist, ruthenium red (10 microM) or capsazepine (5 microM), abolished capsaicin-induced vasodilation and significantly decreased the PNS-induced vasodilation. The decreased PNS-induced vasodilation by ruthenium red or capsazepine was not affected by perfusion of lafutidine. These results suggest that lafutidine facilitates CGRP nerve-mediated vasodilation by modulating the function of presynaptic vanilloid-1 receptors located in CGRPergic nerves.

Topics: Acetamides; Animals; Calcitonin Gene-Related Peptide; Capsaicin; Drug Synergism; Electric Stimulation; Male; Mesenteric Arteries; Peripheral Nervous System; Piperidines; Pyridines; Rats; Rats, Wistar; Ruthenium Red; TRPV Cation Channels; Vasodilation

Acid antisecretory agents are used for the prophylaxis of cancer chemotherapy (CT)-induced gastrointestinal (GI) mucositis. Although these drugs seem to be clinically beneficial, data on their effects on the GI mucosal defense during CT treatment are scant. The objective of this study was to compare the effects of omeprazole, lansoprazole, and lafutidine on mucin, a major mucus component, during 5-fluorouracil (5-FU) treatment, as a CT regimen.. Rats, weighing approximately 230 g, were divided into five groups. The control group was administered 0.5% carboxymethylcellulose orally once daily for 5 days. The second, third, fourth, and fifth groups were treated with 5-FU (50 mg/kg), 5-FU plus omeprazole (10 mg/kg), 5-FU plus lansoprazole (10 mg/kg), and 5-FU plus lafutidine (30 mg/kg) in the same way, respectively. The rats were sacrificed on the sixth day, and their stomachs and small intestines were removed. Using anti-mucin monoclonal antibodies, we compared the immunoreactivity in different areas of the rats' GI tracts as well as the mucin content.. Body-weight decreased in rats in the 5-FU group. Lafutidine, but neither omeprazole nor lansoprazole, inhibited the 5-FU-induced weight loss. Mucosal damage and reduced mucin content in stomach and small intestine were observed in rats receiving 5-FU alone. In the stomach, all antisecretory drugs caused the protective effects against 5-FU-induced mucosal injury and alleviation of the decreased mucin accumulation. In the jejunum and ileum, lafutidine, but neither omeprazole nor lansoprazole, ameliorated the 5-FU-induced mucosal damage and decreased mucin accumulation.. Lafutidine could offer the possibility of more effective prevention of CT-induced mucositis through the activation of GI mucus cells.

Topics: 2-Pyridinylmethylsulfinylbenzimidazoles; Acetamides; Animals; Anti-Ulcer Agents; Antimetabolites, Antineoplastic; Fluorouracil; Gastric Mucosa; Gastrointestinal Diseases; Intestinal Mucosa; Lansoprazole; Male; Mucins; Mucositis; Omeprazole; Piperidines; Pyridines; Rats; Rats, Wistar

The metabolism of lafutidine in human liver microsomes was studied using liquid chromatography/ion trap mass spectrometry with electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) sources. A total of 14 metabolites were identified including hydroxylated lafutidine and sulfonyl lafutidine as the major metabolites. The chemical properties and the MS(n) behaviors of lafutidine and all of its identified metabolites were studied in detail. Lafutidine had a fragmentation pattern as a result of homolytic bond cleavage in the MS/MS spectrum. This cleavage can form an odd-electron ion with the loss of furan-2-ylmethyl radical (-81 Da with a proton shift), which then sequentially loses neutral groups in the MS(3) spectrum. This fragmentation sequence was also observed from the metabolites with the unchanged sulfinyl moiety. When the sulfinyl moiety was oxidized to the sulfonyl moiety, this fragmentation sequence did not exist, which could be used to identify S-oxidation metabolites of lafutidine. In general, N-oxides could produce distinct [M+H-O](+) ions under LC/APCI-MS due to the thermal activation in the desolvation region of the API source, which could be used to identify N-oxidation metabolites of lafutidine. In order to avoid the possibility of false positives, the MS/MS spectrum of the [M+H-O](+) ion was compared with that of the non-N-oxidation metabolites or parent drug in the APCI source. If they were consistent, the structure could be finally confirmed. The exact masses for lafutidine and lafutidine N-oxide fragment ions were determined using an LTQ/Orbitrap mass spectrometer.

Topics: Acetamides; Chromatography, Liquid; Histamine H2 Antagonists; Humans; Mass Spectrometry; Microsomes, Liver; Molecular Structure; Molecular Weight; Piperidines; Pyridines

Sensory neuron activation reduces water-immersion restraint stress (WIR)-induced gastric mucosal injury by inhibiting neutrophil activation through increase in endothelial production of prostacyclin. This study was designed to examine whether lafutidine, which is an H(2)-receptor antagonist and activates sensory neurons, inhibits neutrophil activation, thereby reducing WIR-induced gastric mucosal injury. Lafutidine enhanced WIR-induced increases in gastric tissue levels of calcitonin gene-related peptide (CGRP) and 6-keto-PGF(1alpha), a stable metabolite of prostacyclin, whereas famotidine, another H(2)-receptor antagonist, did not. Such lafutidine-induced increases in gastric tissue levels of 6-keto-PGF(1alpha) were reversed by pretreatment with capsazepine, an inhibitor of sensory neuron activation, CGRP(8-37), a CGRP antagonist, and indomethacin. Lafutidine inhibited acid-induced exacerbation of gastric mucosal injury in animals subjected to WIR by inhibiting neutrophil activation, whereas famotidine did not. Lafutidine synergistically increased CGRP release from isolated rat dorsal root ganglion neurons in the presence of anandamide, but famotidine did not. These observations suggest that lafutidine might reduce WIR-induced gastric mucosal injury not only by inhibiting acid secretion but also by inhibiting neutrophil activation through enhancement of sensory neuron activation.

Topics: 6-Ketoprostaglandin F1 alpha; Acetamides; Animals; Anti-Ulcer Agents; Arachidonic Acids; Calcitonin Gene-Related Peptide; Capsaicin; Cells, Cultured; Cyclooxygenase Inhibitors; Disease Models, Animal; Endocannabinoids; Famotidine; Ganglia, Spinal; Gastric Acid; Gastric Mucosa; Histamine H2 Antagonists; Indomethacin; Male; Neurons, Afferent; Neutrophil Activation; Peptide Fragments; Piperidines; Polyunsaturated Alkamides; Pyridines; Rats; Rats, Wistar; Restraint, Physical; Stomach Ulcer; Stress, Psychological

Lafutidine, a histamine H(2)-receptor antagonist, inhibits gastric acid secretion during the daytime, however, the relationship between the plasma concentration and the drug response remains unclear. The aim of this study was to compare the pharmacokinetic and pharmacodynamic properties of lafutidine and famotidine following postprandial oral administration. After a lafutidine tablet (10 mg), famotidine tablet (20 mg), or water only (control) was administered, blood samples were taken and intragastric pH was measured. The plasma concentrations of lafutidine and famotidine were determined by HPLC, and the median intragastric pH values per 30 min were used as the degrees of gastric acid suppression. Data were analyzed based on a one-compartment pharmacokinetic model and a sigmoid E(max) pharmacodynamic model. Lafutidine plasma concentrations rapidly increased after administration; famotidine required some time to increase the plasma concentrations, requiring an absorption lag time in the pharmacokinetic model. Between the plasma concentration and DeltapH (the difference in intragastric pH by the drug vs. control), lafutidine showed an anticlockwise hysteresis loop which indicated equilibration delay between the plasma concentration and effect site, requiring an effect site compartment in the pharmacodynamic model; famotidine showed more parallel relationship. These results indicated that the pharmacokinetic and pharmacodynamic properties of lafutidine after postprandial oral administration were different from those of famotidine at least 4.5 h after dosing.

Topics: Absorption; Acetamides; Administration, Oral; Adult; Famotidine; Gastric Acid; Gastric Acidity Determination; Histamine H2 Antagonists; Humans; Male; Piperidines; Postprandial Period; Pyridines; Tablets; Time Factors

Topics: 2-Pyridinylmethylsulfinylbenzimidazoles; Acetamides; Administration, Oral; Adult; Drug Therapy, Combination; Histamine H2 Antagonists; Humans; Lansoprazole; Male; Piperidines; Proton Pump Inhibitors; Pyridines

We examined the prophylactic effect of lafutidine, a histamine H2 receptor antagonist, on the morphological and functional derangement of the rat stomach after the administration of 5-fluorouracil (5-FU) in the absence or presence of taurocholate Na (TC). Rats were given 5-FU p. o. once daily for 5 days. After 18 hr fasting, the animals were given omeprazole to inhibit acid secretion. Under urethane anesthesia, the stomach was mounted on an ex-vivo chamber, perfused with 100 mM HCl, and both the transmucosal potential difference (PD) and gastric mucosal blood flow (GMBF) were simultaneously measured before and after exposure of the mucosa to 20 mM TC for 30 min. The 5-FU treatment lowered the basal PD with a decrease in the mucosal height and caused few haemorrhagic lesions in the stomach when perfused with 100 mM HCl for 2 hr. The 5-FU treatment had no influence on the reduced PD response caused by TC, but significantly impaired the increase in GMBF after exposure to TC, resulting a marked aggravation of gastric lesions. Lafutidine, given together with 5-FU for 5 days, significantly antagonized the deleterious effect of 5-FU on the basal PD and the GMBF response to TC, and prevented the aggravation of gastric lesions. These effects of lafutidine were not mimicked by cimetidine and disappeared due to the chemical ablation of capsaicin-sensitive afferent neurons. We conclude that 1) 5-FU treatment caused the morphological and functional derangement of the stomach and increased the mucosal vulnerability against acid, and 2) lafutidine prevents such changes caused by 5-FU treatment, probably mediated through capsaicin-sensitive afferent neurons.

Topics: Acetamides; Animals; Anti-Ulcer Agents; Cimetidine; Dinoprostone; Drug Interactions; Fluorouracil; Gastric Mucosa; Hydrochloric Acid; Male; Membrane Potentials; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley; Regional Blood Flow; Stomach; Stomach Ulcer; Taurocholic Acid

A sensitive and specific liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS) method has been developed and validated for the identification and quantification of lafutidine in human plasma. Lafutidine and internal standard were isolated from plasma samples by liquid-liquid extraction with diethyl ether. The chromatographic separation was accomplished on a stainless-steel column (C18 Shim-pack 5 microm 150 mm x 2.0 mm i.d. Shimadzu) at a flow rate of 0.2 ml/min by a gradient elution. Detection was performed on a single quadrupole mass spectrometer by selected ion monitoring (SIM) mode via electrospray ionization (ESI) source. The method was proved to be sensitive and specific by testing six different plasma batches. Linearity was established for the range of concentrations 1.0-400.0 ng/ml with a coefficient of determination (r) of 0.9998 and good back-calculated accuracy and precision. The intra- and inter-day precision (R.S.D.%) was lower than 10% and accuracy ranged from 85 to 115%. The lower limit of quantification was identifiable and reproducible at 0.5 ng/ml with 0.2 ml plasma. The proposed method enables the unambiguous identification and quantification of lafutidine for pharmacokinetic, bioavailability or bioequivalence studies.

Topics: Acetamides; Calibration; Chemistry, Pharmaceutical; Chromatography, Liquid; Female; Histamine H2 Antagonists; Humans; Male; Mass Spectrometry; Piperidines; Pyridines; Quality Control; Reproducibility of Results; Sensitivity and Specificity; Spectrometry, Mass, Electrospray Ionization; Technology, Pharmaceutical

Lafutidine, a histamine H2 receptor antagonist, exhibits gastro-protective action mediated by capsaicin-sensitive afferent neurons (CSN). We compared the effect between lafutidine and capsaicin, with respect to the interaction with endogenous prostaglandins (PG), nitric oxide (NO) and the afferent neurons, including transient receptor potential vanilloid subtype 1 (TRPV1).. Male SD rats and C57BL/6 mice, both wild-type and prostacyclin IP receptor knockout animals, were used after 18 h of fasting. Gastric lesions were induced by the po administration of HCl/ethanol (60% in 150 mmol/L HCl) in a volume of 1 mL for rats or 0.3 mL for mice.. Both lafutidine and capsaicin (1-10 mg/kg, po) afforded dose-dependent protection against HCl/ethanol in rats and mice. The effects were attenuated by both the ablation of CSN and pretreatment with N(G)-nitro-L-arginine methyl ester, yet only the effect of capsaicin was mitigated by prior administration of capsazepine, the TRPV1 antagonist, as well as indomethacin. Lafutidine protected the stomach against HCl/ethanol in IP receptor knockout mice, similar to wild-type animals, while capsaicin failed to afford protection in the animals lacking IP receptors. Neither of these agents affected the mucosal PGE2 or 6-keto PGF(1alpha) contents in rat stomachs. Capsaicin evoked an increase in [Ca2+]i in rat TRPV1-transfected HEK293 cells while lafutidine did not.. These results suggest that although both lafutidine and capsaicin exhibit gastro-protective action mediated by CSN, the mode of their effects differs regarding the dependency on endogenous PGs/IP receptors and TRPV1. It is assumed that lafutidine interacts with CSN at yet unidentified sites other than TRPV1.

Topics: 6-Ketoprostaglandin F1 alpha; Acetamides; Animals; Calcium; Capsaicin; Dinoprostone; Dose-Response Relationship, Drug; Gastric Mucosa; Histamine H2 Antagonists; Humans; Indomethacin; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Neurons, Afferent; NG-Nitroarginine Methyl Ester; Piperidines; Prostaglandins; Pyridines; Rats; Rats, Sprague-Dawley; Receptors, Epoprostenol; Stomach; Stomach Diseases; TRPV Cation Channels

The cis and trans isomers separation of 2-butene-1,4-diol and lafutidine were studied by HPLC on two kinds of chiral columns: (S,S)-Whelk-O 1 and ChiraSpher. The isomers of 2-butene-1,4-diol can be separated on both chiral columns while the isomers of lafutidine can only be resolved on ChiraSpher column. The influence of different type and amount of mobile phase modifier on the isomers separation was extensively studied. The resolution of cis and trans isomers of 2-butene-1,4-diol was 2.61 on (S,S)-Whelk-O 1 column with hexane-ethanol (97:3, v/v) as the mobile phase. The resolution of lafutidine was 1.89 on ChiraSpher column with hexane-ethanol-THF-diethylamine (92:3:5:0.1, v/v/v/v) as the mobile phase. LC-MS methods were developed to identify the isomer peaks.

Topics: Acetamides; Butylene Glycols; Chemical Fractionation; Chromatography, High Pressure Liquid; Isomerism; Mass Spectrometry; Piperidines; Pyridines

Lafutidine, a histamine H(2) receptor antagonist, exerts gastroprotective effects in addition to gastric antisecretory activity. The gastrointestinal protective effects of lafutidine are mediated by capsaicin-sensitive neurons, where capsaicin excites neurons by opening a member of the transient receptor potential channel family (TRPV1). Since the effect of lafutidine on the intracellular Ca(2+) concentration ([Ca(2+)](i)) in cells has not been elucidated, we investigated the lafutidine response to [Ca(2+)](i) in rat pheochromocytoma PC12 and human endothelial cells. Lafutidine at pharmacological concentrations greater than 1 mM induced a sustained increase in [Ca(2+)](i) in the presence of extracellular CaCl(2) in PC12 cells, while capsaicin showed dual effects on [Ca(2+)](i) in PC12 cells, where it activated TRPV1 and inhibited store-operated Ca(2+) entry. The thapsigargin (an activator of store-operated Ca(2+) entry)-induced increase in [Ca(2+)](i) in PC12 cells was inhibited by capsaicin and SKF96365, an inhibitor of store-operated Ca(2+) entry, and the lafutidine response was inhibited by capsaicin but not by SKF96365. In endothelial cells, lafutidine induced an increase in [Ca(2+)](i) in a SKF96365-insensitive manner. These results suggest that lafutidine stimulates Ca(2+) entry via the capsaicin-sensitive pathway but not the SKF96365-sensitive pathway. The possible role of store-operated Ca(2+) entry induced by lafutidine on gastrointestinal function is also discussed.

Topics: Acetamides; Animals; Calcium; Calcium Chloride; Capsaicin; Dose-Response Relationship, Drug; Endothelial Cells; Humans; Imidazoles; Immunoblotting; Intracellular Fluid; PC12 Cells; Piperidines; Pyridines; Rats; Thapsigargin; Time Factors

Topics: 2-Pyridinylmethylsulfinylbenzimidazoles; Acetamides; Benzimidazoles; Gastric Acid; Gastric Acidity Determination; Heartburn; Helicobacter Infections; Helicobacter pylori; Histamine H2 Antagonists; Humans; Hydrogen-Ion Concentration; Omeprazole; Piperidines; Prognosis; Proton Pump Inhibitors; Pyridines; Rabeprazole; Severity of Illness Index; Treatment Outcome

A rapid, sensitive and specific high-performance liquid chromatography-electrospray ionization mass spectrometry (LC/ESI-MS) method was developed and validated for the first time to determine the concentration of lafutidine in human plasma. After the addition of diazepam (the internal standard, IS) and 1 M sodium hydroxide solution to 0.5-ml plasma sample, lafutidine was extracted from plasma with n-hexane : isopropanol (95 : 5, v/v). The organic layer was evaporated and the residue was redissolved in 200-microl mobile phase. The analyte was chromatographically separated on a prepacked Shimadzu Shim-pack VP-ODS C(18) column (250 x 2.0 mm i.d.) using a mixture of methanol-water (20 mM CH(3)COONH(4)) = 80 : 20 (v/v) as mobile phase. Detection was performed on a single quadrupole mass spectrometer using an electrospray ionization interface and the selected-ion monitoring (SIM) mode. The method showed excellent linearity (r = 0.9993) over the concentration range of 5-400 ng/ml and had good accuracy and precision. The within- and between-batch precisions were within 10% relative standard deviation. The limit of detection was 1 ng/ml. The validated LC/ESI-MS method has been successfully applied to the bioequivalence study of lafutidine in 24 healthy male Chinese volunteers.

Topics: Acetamides; Chromatography, High Pressure Liquid; Drug Stability; Histamine H2 Antagonists; Humans; Male; Piperidines; Pyridines; Reproducibility of Results; Sensitivity and Specificity; Spectrometry, Mass, Electrospray Ionization; Therapeutic Equivalency

Attachment of Helicobacter pylori to gastric epithelial cells leads to the production of chemokines, such as interleukin-8 (IL-8), which in turn activate and recruit neutrophils to the site of infection. Lafutidine [(+/-)-2-(furfurylsulfinyl)-N-(4-(4-(piperidinomethyl)-2-pyridyl)oxy-(Z)-2-butenyl)acetamide] is a new type of antiulcer drug that possesses an antisecretory action as well as gastroprotective activity, independent of its antisecretory action. In the present study, we examined the effects of lafutidine on H. pylori-induced IL-8 release and H. pylori adhesion to MKN45 cells.. MKN45 cells were stimulated with H. pylori, tumor necrosis factor (TNF)-alpha, or IL-1beta, then IL-6 and IL-8 levels in the culture supernatants were determined with a specific enzyme-linked immunosorbent assay kit.. Lafutidine significantly inhibited both the release of IL-8 induced by H. pylori and the adhesion of H. pylori to cells in a dose-dependent manner. These properties of lafutidine are unrelated to the blockade of histamine H(2)-receptors, because the same effects have not been observed with other H(2)-receptor antagonists, such as cimetidine and famotidine. Lafutidine also significantly inhibited H. pylori-induced IL-6 release. Both TNF-alpha and IL-1beta-induced IL-8 releases, conversely, were little affected by lafutidine up to a concentration of 10(-5) M.. These results suggest that lafutidine inhibits IL-8 release by inhibiting H. pylori adherence to gastric epithelial cells, indicating a novel mechanism by which lafutidine protects against the mucosal inflammation associated with H. pylori infection.

Topics: Acetamides; Anti-Ulcer Agents; Bacterial Adhesion; Cell Line; Cells, Cultured; Gastric Mucosa; Helicobacter pylori; Humans; Interleukin-1; Interleukin-6; Interleukin-8; Piperidines; Pyridines; Tumor Necrosis Factor-alpha

Effects of vanilloid-receptor agonists and antagonists on HCl-induced gastric lesions in rats were investigated to elucidate the role of vanilloid receptor type 1 (VR1) in gastric mucosal defense mechanisms.. Gastric lesions in rats were evaluated after intragastric administration of 0.6 N HCl. The localization of VR1 in the stomach was investigated immunohistochemically.. Intragastric administration of capsaicin inhibited the formation of gastric lesions in a dose-dependent manner (0.1-2.5 mg/kg). The functional VR1 antagonists ruthenium red and capsazepine markedly aggravated HCl-induced gastric lesions in rats. The gastroprotective effect of capsaicin was attenuated by ruthenium red or capsazepine. It is reported that resiniferatoxin, [6]-gingerol and lafutidine are compounds that activate VR1 and/or capsaicin-sensitive afferent neurons. These compounds significantly inhibited the formation of HCl-induced gastric lesions, and their gastroprotective effects were inhibited by treatment with ruthenium red. The immunohistochemical studies revealed that nerve fibers expressing VR1 exist along gastric glands in the mucosa, around blood vessels in the submucosa, in the myenteric plexus, and in the smooth muscle layers, especially the circular muscle layer.. The results of this study suggest that VR1 plays a protective role in the gastric defensive mechanism in rats.

Topics: Acetamides; Animals; Anti-Ulcer Agents; Capsaicin; Catechols; Diterpenes; Famotidine; Fatty Alcohols; Gastric Mucosa; Hydrochloric Acid; Male; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley; Receptors, Drug; Stomach Ulcer

Lafutidine, a histamine H2-receptor antagonist, exhibits gastric mucosal protective action mediated by capsaicin-sensitive afferent neurons, in addition to a potent antisecretory effect. In this study we examined the effect of lafutidine on dextran sulfate Na (DSS)-induced ulcerative colitis in rats, in relation to capsaicin-sensitive afferent neurons. Experimental colitis was induced in rats by daily treatment with 3% DSS in drinking water for 7 days. Lafutidine, capsaicin, and cimetidine were administered per os twice daily for 6 days. The ulceration area, colon length, and myeloperoxidase (MPO) activity were measured on day 7 after the onset of DSS treatment. DSS caused severe mucosal lesions in the colon, accompanied by an increase in MPO activity as well as a decrease in body weight gain and colon length. Daily administration of lafutidine dose-dependently reduced the severity of DSS-induced colitis and significantly mitigated changes in the colon length and MPO activity. The effects of lafutidine were mimicked by daily administration of capsaicin but not cimetidine and were totally abolished by chemical ablation of capsaicin-sensitive afferent neurons. In contrast, desensitization of afferent neurons significantly worsened the colonic inflammation induced by DSS. It was also found that both lafutidine and capsaicin increased the secretion of mucus in the colonic mucosa. These results suggest that lafutidine is effective against the ulcerative colitis induced by DSS through capsaicin-sensitive afferent neurons. This action might be attributable at least partly to the enhancement of colonic mucus secretion.

Topics: Acetamides; Animals; Capsaicin; Colitis, Ulcerative; Dextran Sulfate; Histamine H2 Antagonists; Intestinal Mucosa; Male; Neurons, Afferent; Peroxidase; Piperidines; Pyridines; Rats; Rats, Wistar

Lafutidine, (+/-)-2-(furfurylsulfinyl)-N-[4-[4-(piperidinomethyl)-2-pyridyl]oxy-(Z)-2 butenyl]acetamide, is a newly synthesized histamine H2 receptor antagonist and possesses a cytoprotective efficacy, which comprises mucin biosynthesis and stimulation of gastric blood flow mediated through capsaicin-sensitive sensory neurons and endogenous calcitonin gene-related peptide (CGRP). In the present study, an effect of lafutidine on hepatic blood flow was investigated in rats that received an intracisternal injection of a subthreshold dose of thyrotropin-releasing hormone (TRH) analog, RX 77368.. Change in hepatic blood flow was determined by laser Doppler flowmetry. Male Wistar rats were anesthetized with urethane (1.5 g/kg, i.p.), and positioned on a stereotaxic apparatus. An abdominal incision was made, and a probe of laser Doppler flowmeter was placed on the surface of the liver. After a 60-min stabilization, basal hepatic blood flow was measured for 30 min, and lafutidine (0.5, 1, 3, 5 or 10 mg/kg) or vehicle was injected into the portal vein and a subthreshold dose (1.5 ng) of RX 77368 was injected intracisternally. Hepatic blood flow was monitored for 120 min postinjection. To investigate a role of capsaicin-sensitive sensory neurons and endogenous CGRP, systemic capsaicin treatment (125 mg/kg, s.c., 10-14 days before) and intravenous infusion of a CGRP receptor antagonist, human CGRP-(8-37) (15 micro g/kg as a bolus, followed by infusion at 3 micro g/kg/h) were performed, respectively.. Intracisternal injection of RX 77368 (1.5 ng) or intraportal lafutidine (10 mg/kg) by itself did not affect hepatic blood flow, but co-injection of intracisternal RX 77368 (1.5 ng) and intraportal lafutidine (5 mg/kg) increased it with peak response at 30 min postinjection. The effect of lafutidine on hepatic blood flow in rats given RX 77368 was dose-related over the range 1-5 mg/kg. By contrast, intracisternal injection of RX 77368 (1.5 ng) did not change hepatic blood flow in rats injected with another histamine H2 receptor antagonist, famotidine (5 mg/kg), intraportally. The stimulatory effect of co-injection of TRH analog and lafutidine was abolished by systemic capsaicin-treatment and CGRP antagonist.. These data suggest that lafutidine increases hepatic blood flow by sensitizing the liver to the action of central TRH via both capsaicin-sensitive sensory neurons and endogenous CGRP in urethane-anesthetized rats.

Topics: Acetamides; Analysis of Variance; Animals; Capsaicin; Drug Combinations; Drug Synergism; Gastric Mucosa; Histamine H2 Antagonists; Laser-Doppler Flowmetry; Liver; Liver Circulation; Male; Neurons, Afferent; Piperidines; Pyridines; Pyrrolidonecarboxylic Acid; Rats; Rats, Wistar; Receptors, Calcitonin Gene-Related Peptide; Thyrotropin-Releasing Hormone

Lafutidine is a novel histamine H(2)-receptor antagonist with a potent and long-lasting anti-acid secretory effect that has also been found to have a potent gastroprotective effect. We investigated the effect of lafutidine on gastric mucosal injury induced in rats with the use of water-immersion restraint stress (WRS) by examining serum calcitonin gene-related peptide (CGRP) concentrations, which we measured with the use of an enzyme immunometric assay. WRS-induced mucosal erosive injury in the stomach was reduced significantly by both lafutidine and famotidine pretreatment (from 7.79 +/- 2.02 mm(2) to 3.09 +/- 0.74 mm(2) and 4.05 +/- 1.18 mm(2), respectively). A single administration of lafutidine or famotidine did not change the serum CGRP concentration from the control value when these drugs were administered without WRS. Lafutidine pretreatment before WRS caused a significant increase in serum CGRP concentration compared with famotidine (lafutidine, 86.64 +/- 9.52 pg/mL; famotidine, 47.55 +/- 4.35 pg/mL; control, 58.43 +/- 6.07 pg/mL). Our results suggest that lafutidine augments CGRP release from the rat stomach when administered before the induction of WRS.

Topics: Acetamides; Animals; Calcitonin Gene-Related Peptide; Famotidine; Histamine H2 Antagonists; Immersion; Male; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley; Restraint, Physical; Stomach Ulcer; Stress, Physiological; Water

Topics: Acetamides; Animals; Anti-Ulcer Agents; Calcitonin Gene-Related Peptide; Dose-Response Relationship, Drug; Enterohepatic Circulation; Gastric Mucosa; Histamine H2 Antagonists; Humans; Liver; Piperidines; Pyridines

Topics: Acetamides; Adolescent; Anesthesia, General; Child; Child, Preschool; Cimetidine; Gastric Acid; Gastric Acidity Determination; Gastric Juice; Histamine H2 Antagonists; Humans; Piperidines; Pneumonia, Aspiration; Pyridines

A segment of guinea pig ileum was used to confirm the hypothesis that [6]-gingerol and lafutidine interact with capsaicin-sensitive neurons. Addition of 30 and 100 microM [6]-gingerol (a pungent constituent of ginger) induced contraction of the ileum immediately. Like capsaicin, [6]-gingerol-induced contraction was inhibited by antagonists of the vanilloid receptor (capsazepine and ruthenium red), tetrodotoxin, and atropine. Treatment with [6]-gingerol up to 0.3 microM, which alone had no effect, enhanced 3 microM capsaicin-induced contraction, but greater than 3 microM [6]-gingerol significantly inhibited capsaicin-induced contraction. Treatment with lafutidine (a new type of antagonist of the histamine H(2) receptor), which was suggested to interact with capsaicin-sensitive neurons in vivo, also showed both stimulatory and inhibitory effects on capsaicin-induced contraction depending on the concentrations. Lafutidine alone had no effect. The enhanced contraction induced by capsaicin in the [6]-gingerol- or lafutidine-treated ileum was also inhibited by antagonists of the vanilloid receptor, tetrodotoxin, and atropine. Capsaicin and [6]-gingerol, but not lafutidine, at 30 microM stimulated [(3)H]choline release from the prelabeled slices of the ileum. These findings suggest that [6]-gingerol and lafutidine act on capsaicin-sensitive cholinergic neurons and modulate the contraction in isolated guinea pig ileum.

Topics: Acetamides; Animals; Capsaicin; Catechols; Dose-Response Relationship, Drug; Fatty Alcohols; Guinea Pigs; Ileum; In Vitro Techniques; Male; Muscle Contraction; Neurons; Piperidines; Pyridines

It is well known that capsaicin-sensitive nerve signaling acts as a protective factor against various ulcerogens. However, the contribution of topical capsaicin-sensitive nerves within the stomach to rapid restitution has not been fully investigated. The present study was therefore conducted focusing on recovery from gastric mucosal damage induced by ethanol in vivo.. Male Sprague-Dawley rats were fasted and anesthetized. 51Cr-EDTA was administered intravenously and gastric mucosal integrity was continuously monitored by measuring the blood to lumen 51Cr-EDTA clearance. Capsaicin or vehicle was irrigated before, together with or after the perfusion of 20% ethanol, followed by perfusion with saline. In another experiment, ruthenium red, a capsaicin-sensitive cation antagonist, was given before the ethanol-capsaicin perfusion. Furthermore, this study was verified using lafutidine, a histamine H2-receptor antagonist, which has a gastric mucosal protective action through the capsaicin-sensitive afferent nerves.. When capsaicin was administered before ethanol treatment, mucosal damage was significantly reduced and recovery was significantly rapid compared to the control. When capsaicin (160 micro M) and ethanol were administered simultaneously, the mucosal damage was exacerbated but recovery was nevertheless more rapid than the control group. With a lower dose of capsaicin (80 micro M), mucosal damage was not exacerbated and recovery was enhanced. When capsaicin or lafutidine was administered after the induction of ethanol injury no change was detected regarding the damage. However, recovery was significantly accelerated. Ruthenium red reversed the action of post-treatment with capsaicin on restitution.. These results indicate that luminal administration of capsaicin exerts protection against and accelerates restitution from gastric damage in the very early phase after ethanol injury. This action is probably due to activation of topical capsaicin-sensitive afferent nerves in the rat.

Topics: Acetamides; Animals; Anti-Ulcer Agents; Capillary Permeability; Capsaicin; Edetic Acid; Ethanol; Gastric Mucosa; Male; Neurons, Afferent; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley; Ruthenium Red; Stomach Ulcer

We examined the effect of lafutidine, a novel histamine H(2)-receptor antagonist, on acid reflux esophagitis in rats in relation to capsaicin-sensitive afferent neurons. The esophagitis was induced in rats by ligating both the pylorus and forestomach for 4 h. Lafutidine (1 - 30 mg/kg) and cimetidine (100 mg/kg) were administered either intragastrically or intraduodenally, while capsaicin (1 - 30 mg/kg) was administered intragastrically after the dual ligation. Intragastrical administered lafutidine at >3 mg/kg significantly prevented the hemorrhagic esophageal damage induced by the dual ligation, and this effect was mimicked by neither capsaicin nor cimetidine given intragastrically, but totally abolished by sensory deafferentation. In contrast, lafutidine and cimetidine given intraduodenally were both protective against the esophageal damage in a sensory deafferentation-resistant manner. The acid secretion in pylorus-ligated stomachs was significantly inhibited by these agents given intraduodenally, but not intragastrically. Vanilloid receptor subtype 1 (VR1) was expressed abundantly in the stomach, but very weakly expressed in the esophagus as assessed by Western blotting. These results suggest that lafutidine is effective against the esophageal lesions induced by acid reflux through inhibition of acid secretion and capsaicin-sensitive afferent neurons. The latter mechanism, not shared by cimetidine, may be due to the interaction of lafutidine with unidentified sites on sensory neurons other than VR1.

Topics: Acetamides; Animals; Capsaicin; Dose-Response Relationship, Drug; Esophagitis, Peptic; Histamine Antagonists; Male; Neurons, Afferent; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley; Receptors, Histamine H2

Lafutidine is a new type of antiulcer drug, possessing both an antisecretory effect, exerted via a blockade of the histamine H2 receptor, and gastroprotective activity, mediated by capsaicin-sensitive afferent nerves (CSN). In the present study, we examined the effect of lafutidine on gastric mucosal blood flow (GMBF) and duodenal HCO3- secretion (DAS) under basal and acid-stimulated conditions in rats. Under urethane anesthesia, GMBF was measured using a laser Doppler flowmeter in a chambered stomach before and after exposure to 20 mM taurocholate (TC) plus 50 mM HCl, while DAS was measured in a proximal duodenal loop before and after mucosal acidification (10 mM HCl for 10 min) by titrating the perfusate at pH 7.0 using a pH-stat method and by adding 10 mM HCl. Lafutidine given intraperitoneally affected neither GMBF nor DAS under basal conditions, but augmented an increase in both GMBF and DAS induced by mucosal acidification. Although the acid-induced GMBF and DAS responses were significantly mitigated by both indomethacin and sensory deafferentation but not by ruthenium red (RT), the vanilloid receptor (VR)-1 antagonist, the responses were preserved in lafutidine-treated animals, even in the presence of indomethacin. Both GMBF and DAS were significantly increased by local application of capsaicin, the responses being attenuated by indomethacin and RT as well as sensory deafferentation. Lafutidine augmented the GMBF and DAS responses to capsaicin and preserved the responses, even in the presence of indomethacin. Capsaicin evoked an increase in [Ca2+]i in rat VR1-transfected HEK293 cells, while lafutidine had no effect by itself on [Ca2+]i in these cells and did not affect the increase in [Ca2+]i evoked by capsaicin. In conclusion, these results suggest that lafutidine mimics endogenous effects of prostaglandins to augment the GMBF and DAS responses to acid or capsaicin, probably by sensitizing CSN through an unknown site other than VR1. The luminal H+ itself is not a ligand for the RT-sensitive site of VR1 but plays a modulator role in the CSN-mediated physiological responses.

Topics: Acetamides; Animals; Bicarbonates; Capsaicin; Cells, Cultured; Coloring Agents; Duodenum; Gastric Mucosa; Histamine H2 Antagonists; Male; Neurons, Afferent; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley; Receptors, Drug; Regional Blood Flow; Ruthenium Red

1. Capsaicin sensitive afferent nerves play an important role in gastric mucosal defensive mechanisms. Capsaicin stimulates afferent nerves and enhances the release of calcitonin gene-related peptide (CGRP), which seems to be the predominant neurotransmitter of spinal afferents in the rat stomach, exerting many pharmacological effects by a direct mechanism or indirectly through second messengers such as nitric oxide (NO). 2. Lafutidine is a new type of anti-ulcer drug, possessing both an antisecretory effect, exerted via histamine H(2) receptor blockade, and gastroprotective activities. Studies with certain antagonists or chemical deafferentation techniques suggest the gastroprotective actions of lafutidine to be mediated by capsaicin sensitive afferent nerves, but this is an assumption based on indirect techniques. In order to explain the direct relation of lafutidine to afferent nerves, we conducted the following studies. 3. We determined CGRP and NO release from rat stomach and specific [(3)H]-resiniferatoxin (RTX) binding to gastric vanilloid receptor subtype 1 (VR1), which binds capsaicin, using EIA, a microdialysis system and a radioreceptor assay, respectively. 4. Lafutidine enhanced both CGRP and NO release from the rat stomach induced by a submaximal dose of capsaicin, but had no effect on specific [(3)H]-RTX and capsaicin binding to VR1. 5. In conclusion, our findings demonstrate that lafutidine modulates the activity of capsaicin sensitive afferent nerves in the rat stomach, which may be a key mechanism involved in its gastroprotective action.

Topics: Acetamides; Animals; Anti-Ulcer Agents; Calcitonin Gene-Related Peptide; Capsaicin; Dose-Response Relationship, Drug; Gastric Mucosa; Male; Neurons, Afferent; Nitric Oxide; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley; Stomach

We examined the effects of the histamine H2-receptor antagonist, lafutidine, on the levels of gastrointestinal peptides (somatostatin, calcitonin gene-related peptide (CGRP), gastrin, secretin, and motilin) in plasma from healthy subjects. After a single oral administration of lafutidine (10 mg), the plasma lafutidine level (186 +/- 13.4ng/ml) was highest in the 60-min sample after administration and then the plasma level fell. Lafutidine caused significant increase in plasma somatostatin levels at 20 to 120 min and in CGRP levels at 40 to 120 min, compared with a placebo group. The physiological release of plasma secretin was reduced by administration of lafutidine, but the medicine did not alter the level of gastrin or motilin. These results suggest that the pharmacological effects of lafutidine on regulation of gastrointestinal functions closely relate to changes of somatostatin-, CGRP- and secretin-immunoreactive substance levels in human plasma.

Topics: Acetamides; Adult; Anti-Ulcer Agents; Calcitonin Gene-Related Peptide; Humans; Immunoenzyme Techniques; Male; Piperidines; Pyridines; Secretin; Somatostatin

Defunctionalization of capsaicin-sensitive afferent nerves by pretreatment with a neurotoxic dose of capsaicin aggravates gastric ulcers in rats. In the present study, we investigated the roles of vanilloid receptors in gastric antral ulcers, using vanilloid receptor agonists and antagonists. Gastric antral ulcers were induced by a combination of diethyldithiocarbamate and 1 N HCl in refed rats. The administration of ruthenium red (1.5 mg/kg, s.c., twice daily) aggravated gastric antral ulcers (ulcer index: control, 33.7+/-13.7 mm(2); ruthenium red, 99.9+/-11.0 mm(2)). A similar result was observed in rats pretreated with a neurotoxic dose of capsaicin. On the other hand, capsaicin (1-10 mg/kg, p.o., twice daily) inhibited antral ulcer formation (ulcer index: control, 99.2+/-20.6 mm(2); capsaicin 10 mg/kg, 37.0+/-11.7 mm(2)). A similar effect was obtained in rats treated with the novel antiulcer drug, lafutidine (3-10 mg/kg, p.o., twice daily), which has gastroprotective activity mediated by capsaicin-sensitive afferent nerves. The antiulcer effects of capsaicin and lafutidine were abolished by ruthenium red and by pretreatment with a neurotoxic dose of capsaicin. These results suggest that vanilloid receptors play a gastroprotective role in gastric antral ulcers. In addition, treatment with ruthenium red may be an alternative tool for defunctionalization of capsaicin-sensitive afferent nerves.

Topics: Acetamides; Animals; Anti-Ulcer Agents; Capsaicin; Cations; Ditiocarb; Famotidine; Ion Channels; Male; Piperidines; Pyloric Antrum; Pyridines; Rats; Rats, Sprague-Dawley; Receptors, Drug; Ruthenium Red; Stomach Ulcer

Based on animal models, lafutidine, a novel histamine H(2) receptor (H(2)R) antagonist, is reported to show potent and long-lasting antagonisms of histamine H(2)R-mediated effects. However, no reports have been published concerning its direct interaction with the human H(2)R. This study aims at characterizing its interaction with human H(2)R.. Chinese hamster ovary cell lines stably expressing human H(2)Rs were obtained. The dose-dependent effects of lafutidine and famotidine on [(3)H]tiotidine binding and histamine-stimulated cAMP production were analyzed. The effects of preincubation with 2.78 x 10(-7) M of lafutidine or famotidine for 30 min on histamine-dependent cAMP production and [(3)H]tiotidine binding were also examined after 0, 1, 2, 4, and 12 h. This concentration is below the C(max) of lafutidine (10 mg p.o.) and above the C(max) of famotidine (20 mg p.o.).. Lafutidine inhibited [(3)H]tiotidine binding and histamine-stimulated cAMP production as or more potently than famotidine. At higher concentrations lafutidine was more potent than famotidine. In addition, preincubation with 2.78 x 10(-7) M lafutidine, but not with 10(-5) M famotidine, had marked inhibitory effects which persisted as long as after extensive washing.. Lafutidine shows a potent and long-lasting antagonism on the human H(2)R.

Topics: Acetamides; Animals; CHO Cells; Cimetidine; Cricetinae; Cyclic AMP; Dose-Response Relationship, Drug; Famotidine; Histamine H2 Antagonists; Humans; Piperidines; Pyridines; Receptors, Histamine H2; Transfection

We examined the prophylactic effect of lafutidine, a novel histamine H(2)-receptor antagonist [(+/-)-2-(furfurylsulfinyl)-N-[4-[4-(piperidinomethyl)-2-pyr idyl]oxy- (Z)-2 butenyl]acetamide], on indomethacin-induced small intestinal ulcers in rats and investigated the relation of this action to capsaicin-sensitive sensory neurons.. Subcutaneously administered indomethacin (10 mg/kg) provoked ulceration in the small intestine, mainly the jejunum and ileum, accompanied by increases in myeloperoxidase (MPO) and inducible nitric oxide synthase (iNOS) activities as well as the enterobacterial numbers invading the mucosa. Intestinal ulcerogenic response to indomethacin was prevented by 16,16-dimethyl prostaglandin E(2) (10 microg/kg, p.o.) and capsaicin (10 mg/kg, p.o. ) as well as ampicillin (800 mg/kg, p.o.), but not omeprazole (100 mg/kg, p.o.). Likewise, lafutidine (1-10 mg/kg, p.o.), but not cimetidine (100 mg/kg, p.o.), reduced the occurrence of intestinal ulcers in response to indomethacin in a dose-dependent manner, and a significant effect was observed at 3 mg/kg or greater. The protective action of lafutidine as well as capsaicin was almost totally abolished by chemical ablation of capsaicin-sensitive sensory neurons. Both lafutidine and capsaicin significantly suppressed the increases in MPO and iNOS activities as well as enterobacterial numbers in the mucosa. These agents also significantly enhanced mucus secretion in the small intestine.. These results suggest that lafutidine protects the small intestine against ulceration via stimulation of capsaicin-sensitive sensory neurons. This action may be attributable to inhibition of enterobacterial invasion in the intestinal mucosa, probably by increasing the mucus secretion.

Topics: 16,16-Dimethylprostaglandin E2; Acetamides; Ampicillin; Animals; Capsaicin; Dose-Response Relationship, Drug; Duodenal Ulcer; Histamine H2 Antagonists; Indomethacin; Intestinal Mucosa; Male; Neurons, Afferent; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley

We investigated the recurrence of ulcers in rats after treatment with FRG-8813, (+/-)-2-(furfurylsulfinyl)-N-[4- [4-(piperidinomethyl)-2-pyridyl] oxy-(Z)-2-butenyl] acetamide, a novel histamine H(2)-receptor antagonist. Chronic gastric ulcers were induced by serosa-searing with a hot metal bar, and the ulcer healing and recurrence after treatment with FRG-8813 or famotidine were evaluated by endoscopy for 160 days. At the dose of 30 mg/kg p. o., once daily, the treatment with FRG-8813 or famotidine for 60 days, which was stopped earlier if the ulcer had healed, accelerated the ulcer healing significantly. A subsequent follow-up study on the healed rats showed that the cumulative recurrence rate of rats healed by FRG-8813 was lower than that of naturally healed rats or rats healed by famotidine. In many cases of rats healed by FRG-8813, the regenerated mucosa was normal in contrast with the control of famotidine-healed animals. The mucosal regeneration index of the gastric ulcer after 10 days' administration of FRG-8813 was significantly higher than that obtained with famotidine. After cessation of the treatment with famotidine for 7 days, rebound hyperacidity was induced; but such rebound did not occur with FRG-8813. Considering the low recurrence rate of ulcers after FRG-8813 treatment, we suggest that FRG-8813 treatment may provide additional benefits in peptic ulcer therapy.

Topics: Acetamides; Animals; Disease Models, Animal; Endoscopy, Gastrointestinal; Famotidine; Gastric Acidity Determination; Gastrins; Histamine H2 Antagonists; Male; Outcome Assessment, Health Care; Piperidines; Pyridines; Rats; Rats, Wistar; Secondary Prevention; Stomach Ulcer

Lafutidine (CAS 118288-08-7, FRG-8813) is a novel histamine H2-receptor antagonist with gastroprotective activity. The aim of this study was to investigate the property of the gastro-protective activity of lafutidine by examining the effect on ammonia-induced change in transmucosal potential difference (PD), basal gastric mucosal blood flow (GMBF) and noxious agent-induced cell damage. Intragastrical application of lafutidine accelerated the recovery of the PD reduction after exposure of the mucosa to 0.25% ammonia solution and the accelerating effect was abolished by chemical deafferentation, but not with indometacin, a cyclooxygenase inhibitor. The application of capsaicin, as a reference compound, significantly promoted the recovery of the ammonia-induced PD reduction and this effect was not altered with indometacin. Lafutidine given intragastrically caused a sustained increase in GMBF in a dose-dependent fashion, which was also completely inhibited in the deafferentated rats. In vitro studies revealed that, in contrast to 16,16-dimethyl prostaglandin E2, lafutidine did not protect isolated gastric superficial epithelial cells from ethanol- or ammonia-induced damage. In conclusion, the gastroprotection of lafutidine is induced by promoting the restitution of the damaged mucosa after a noxious agent, not by directly protecting the epithelial cells and this effect may be caused through the mechanism of capsaicin-sensitive afferent nerves.

Topics: 16,16-Dimethylprostaglandin E2; Acetamides; Ammonia; Animals; Anti-Inflammatory Agents, Non-Steroidal; Anti-Ulcer Agents; Capsaicin; Central Nervous System Depressants; Ethanol; Gastric Mucosa; Histamine H2 Antagonists; Indomethacin; Male; Membrane Potentials; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley; Stomach Ulcer

Lafutidine is a new type antiulcer agent with antisecretory and gastroprotective activities. We investigated the effect of lafutidine on indomethacin-induced antral ulcer in refed rats. Subcutaneous indomethacin injection resulted in the formation of gastric antral ulcer. Lafutidine (1-10 mg/kg, p.o.) reduced the area of ulcer in a dose-dependent manner when administered immediately after the indomethacin injection. Capsaicin at 3 mg/kg, p.o. and 16,16-dimethyl prostaglandin E2 at 3 microg/kg, p.o. also reduced the ulcer area. Chemical deafferentation of capsaicin-sensitive neurons or N(G)-nitro-L-arginine treatment aggravated the ulcer formation and abolished the preventive effect of lafutidine and capsaicin. After the induction of gastric ulcer, lafutidine given twice daily for 2.5 days reduced the area of ulcer in a dose-dependent manner with a significant effect at 10 mg/kg, p.o., as compared with that of the control group. In chemically-deafferentated rats, lafutidine did not show any healing effect. Cimetidine (30 mg/kg, p.o.) and famotidine (1 mg/kg, p.o.) had no significant effect on indomethacin-induced antral ulcer. These results may suggest that lafutidine, unlike cimetidine and famotidine, can prevent the indomethacin-induced antral ulcer formation and accelerate the healing of the ulcer in refed rats through mechanisms involving the capsaicin-sensitive afferent neurons and nitric oxide.

Topics: 16,16-Dimethylprostaglandin E2; Acetamides; Administration, Oral; Animals; Anti-Ulcer Agents; Capsaicin; Cimetidine; Denervation; Dose-Response Relationship, Drug; Enzyme Inhibitors; Famotidine; Food; Indomethacin; Male; Nitroarginine; Piperidines; Pyloric Antrum; Pyridines; Rats; Rats, Sprague-Dawley; Stomach Ulcer; Wound Healing

Lafutidine ((+/-)-2-(furfurylsulfinyl)-N-(4-(4-(piperidinomethyl)-2-pyr idyl)oxy-(Z)-2-butenyl)acetamide) is a novel histamine H2-receptor antagonist and has been shown to exhibit a potent gastroprotective activity in addition to its antisecretory action. In the present study, we examined the effects of lafutidine on the mucosal ulcerogenic and potential difference (PD) responses induced by monochloramine (NH2Cl) in rat stomachs.. Oral administration of NH2Cl at 120 mmol/L produced haemorrhagic lesions in the stomach in unanaesthetized rats.. Lafutidine (3-30mg/kg), given p.o., showed a dose-dependent and significant inhibition against damage caused by NH2Cl: the effect was significant at 10 mg/kg or greater but disappeared almost totally in the sensory deafferented animals following capsaicin pretreatment. Likewise, capsaicin (10 mg/kg, p.o.), but not cimetidine (100 mg/kg, p.o.) exhibited a potent protection against NH2Cl-induced gastric lesions. Topical application of NH2Cl (10 mmol/L) reduced transmucosal PD in ex-vivo stomachs of anaesthetized rats, but this PD response was also prevented by pre-exposure to lafutidine, in a dose-dependent and sensory neuron-sensitive manner. Mucosal exposure to NH4OH (60 mmol/L) also caused PD reduction in ex-vivo stomachs made ischaemic by bleeding from the carotid artery (1 mL/100 g bodyweight), resulting in severe gastric lesions. These ulcerogenic and PD responses caused by NH4OH plus ischaemia were attenuated by prior application of lafutidine as well as taurine, a scavenger of NH2Cl. The former effect was, again, dependent on the sensory neurons. Intraluminal capsaicin but not cimetidine was also effective in preventing a PD response to NH2Cl.. These results suggest that lafutidine, but not cimetidine, protects the stomach against NH2Cl, whether occurring endogenously or administered exogenously and that this action may be mediated by capsaicin-sensitive sensory neurons.

Topics: Acetamides; Animals; Anti-Ulcer Agents; Capsaicin; Chloramines; Cimetidine; Gastric Mucosa; Histamine H2 Antagonists; Ischemia; Membrane Potentials; Neurons, Afferent; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley; Stomach; Stomach Ulcer

We recently found that N-[3-[3-(piperidinomethyl)phenoxyl]propyl]acetamide derivatives with a thioether function showed gastric anti-secretory and gastroprotective activities and that the thioether function (particularly furfurylthio or furfurylsulfinyl) was essential for gastroprotection. In the present study, a series of 2-furfurylthio and 2-furfurylsulfinyl acetamide derivatives were synthesized and evaluated for histamine H2 receptor antagonistic activity, gastric anti-secretory activity and gastroprotective action. Based on the structure of N-[3-[3-(piperidinomethyl)phenoxyl]propyl]acetamide, we designed compounds, in which the 3-(piperidinomethyl)phenoxy part is substituted with many types of heteroaromatic ring attached to the tertiary amine and the propyl group is replaced with other carbon linkages. Structure-activity relationships are discussed. 2-Furfurylsulfinyl-N-[4-[4-(piperidinomethyl)-2-pyridylox y]- (Z)-2-butenyl]acetamide was the most potent among the tested compounds and was given the code designation FRG-8813.

Topics: Acetamides; Animals; Anti-Ulcer Agents; Gastric Acid; Guinea Pigs; Heart Rate; Histamine; Histamine H2 Antagonists; Male; Piperidines; Pyridines; Rats; Rats, Wistar; Stomach; Structure-Activity Relationship

Effect of lafutidine ((+/-)-2-(furfurylsulfinyl)-N-[4-[4-(piperidinomethyl)-2-pyr idyl] oxy-(Z)-2-butenyl] acetamide, FRG-8813), a novel antiulcer agent, on the healing and relapse in acetic acid-induced gastric ulcer in rats was investigated. Lafutidine at 1, 3 or 10 mg/kg, twice daily for 10 days reduced the ulcer area in a dose-dependent manner, and the effect by 10 mg/kg of lafutidine was significant. The effect of famotidine at 1 mg/kg and cimetidine at 30 mg/kg, which have almost equal antisecretory activity to lafutidine at 10 mg/kg, on the ulcer area was not significant. Effect on the healing and relapse was assessed by endoscopy for 25 weeks after the induction of gastric ulcer. Drugs were administered twice daily for 11 weeks. Lafutidine at 3 mg/kg and famotidine at 1 mg/kg accelerated the healing, but cimetidine at 30 mg/kg did not. Cumulative relapse rate and inflammatory cell infiltration were significantly reduced in rats initially treated with lafutidine. Famotidine and cimetidine had no effect. In conclusion, lafutidine accelerated ulcer healing and prevented ulcer relapse in rats.

Topics: Acetamides; Acetic Acid; Animals; Anti-Ulcer Agents; Cimetidine; Dose-Response Relationship, Drug; Famotidine; Histamine H2 Antagonists; Male; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley; Recurrence; Stomach Ulcer

Although the new histamine H2 receptor antagonist, lafutidine (FRG-8813), N-[4-[4-(piperidinylmethyl)pyridyl-2-oxy]-(Z)-2-butenyl]-2-(fur furylsulfinyl)acetamide accelerates mucin metabolism of rat gastric mucosa, the physiological mechanisms by which this drug stimulates the biosynthesis remain unclear. In this paper, we report the effect of lafutidine on mucin biosynthesis in distinct sites and layers of rat gastric mucosa, including the possible participation of nitric oxide (NO). Lafutidine enhanced [3H]glucosamine incorporation into the mucin in the full thickness corpus mucosa, but not in the antrum. This stimulation on mucin biosynthesis disappeared by the removal treatment of surface mucosal cells. The lafutidine-induced increase of [3H]-labeled mucin in the corpus was completely blocked by either NG-nitro-L-arginine (10[-5] M) or 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazolne-1-oxyl-3-oxide (10[-5] M). The inhibitory action of NG-nitro-L-arginine was totally reversed by L-arginine (5 x 10[-3] M). These results suggest that the lafutidine-induced stimulation of mucin biosynthesis mediated by NO is limited to the surface mucous cells of rat gastric oxyntic mucosa.

Topics: Acetamides; Animals; Benzoates; Enzyme Inhibitors; Free Radical Scavengers; Gastric Mucosa; Glucosamine; Histamine H2 Antagonists; Imidazoles; Male; Mucins; Nitric Acid; Nitric Oxide Synthase; Piperidines; Pyridines; Rats; Rats, Wistar; Stimulation, Chemical

Oral administration of an ammonia solution (0.01%) or a sodium taurocholate solution (TCA solution, 5 mM) as drinking water for 4 weeks or 13 weeks, respectively, resulted in gastric mucosal thinning and decreased parietal cell numbers. Oral administration of TCA solution also caused cell infiltration in the lamina propria of the mucosa and mucosal fibrosis. When lafutidine (3, 10 mg/kg) was administered orally once daily for one week after the withdrawal of ammonia or TCA solution, the recovery of the mucosal thickness in the fundic gland area and the parietal cell number were significantly accelerated, and the recovery of mucosal thickness in the pyloric gland area also tended to be accelerated. Lafutidine at 10 mg/kg for 1 week had no influence on normal mucosal thickness and parietal cell numbers. At the doses that produce equal or greater acid antisecretory effect than lafutidine, oral administration of cimetidine (30 mg/kg) and famotidine (1 mg/kg) had no effect on either of these atrophy indexes. These results demonstrate that lafutidine, unlike cimetidine and famotidine, can accelerate the healing of mucosal injuries in ammonia- and TCA-induced chronic gastritis models.

Topics: Acetamides; Ammonia; Animals; Anti-Ulcer Agents; Cell Count; Chronic Disease; Cimetidine; Famotidine; Gastric Mucosa; Gastritis; Humans; Male; Parietal Cells, Gastric; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley; Taurocholic Acid

Certain chemical properties, which may determine the stimulatory actions of the new histamine H2 receptor antagonist, FRG-8813 (2-(furfurylsulfinyl)-N-(4-[4-(piperidinomethyl)-2-pyridyl]o xy-(Z)- 2-butenyl)acetamide), on mucin biosynthesis, were identified by considering the derivation of this drug using an organ culture system of the rat stomach. [3H]Glucosamine and [35S]sulfate incorporation was stimulated in the corpus region by FRG-8813 and its structural analog, compound A (N-[4-[[4- (piperidinylmethyl)pyridyl]-2-oxy]-(Z)-2-butenyl]phthalimide). The chronotropic response to histamine in the guinea pig right atria was suppressed by FRG-8813 in a concentration-dependent fashion. In contrast, compound A did not suppress the histamine-induced response. Ranitidine at 10(-4) M did not suppress the FRG-8813-induced increase in [3H]glucosamine incorporation into mucin. These results suggest that the pyridine derivative and amide structure are chemically important in FRG-8813 as a stimulant on mucus metabolism. Also, this effect is not directly due to histamine H2 receptor antagonism.

Topics: Acetamides; Animals; Gastric Mucosa; Heart Atria; Heart Rate; Histamine H2 Antagonists; Male; Mucins; Organ Culture Techniques; Piperidines; Proteins; Pyloric Antrum; Pyridines; Rats; Rats, Wistar

FRG-8813 ((+/-)-2-(furfurylsulfinyl)-N-[4-[4-(piperidinomethyl)-2- pyridyl]oxy-(Z)-2-butenyl]acetamide) is a novel histamine H2-receptor antagonist with gastric antisecretory and gastroprotective activities. The present study was designed to investigate the property of gastroprotective action. The oral ED50 values for inhibition of mucosal lesions against 1% NH3-, 60% ethanol in 0.15 N HCl-, 100% ethanol-, 0.6 N HCl- and sodium taurocholate in 0.4 N HCl-induced damage were 3.3, 11.1, 14.9, 23.3 and 23.1 mg/kg, respectively. FRG-8813 was gastroprotective despite pretreatment with omeprazole, suggesting that the protective effect is independent of its antisecretory activity. It is unlikely that FRG-8813 works as a mild irritant because it showed a gastroprotective effect after intraperitoneal injection, but oral administration itself did not influence the rat gastric mucosa. Although pretreatment with indomethacin or N-ethylmaleimide did not affect the gastroprotection of FRG-8813, chemical deafferentation induced by capsaicin abolished the gastroprotection. Furthermore, prior administration of tetrodotoxin, the calcitonin gene-related peptide (CGRP) antagonist hCGRP or NG-nitro-L-arginine attenuated the gastroprotection of FRG-8813 as well as that of capsaicin. In contrast to capsaicin, repeated administration of FRG-8813 neither enhanced the susceptibility of the mucosa to damage nor affected the gastroprotective action of short-term treatment. In conclusion, these results suggest that FRG-8813 has gastroprotective activity independently of acid antisecretory activity and that capsaicin-sensitive nerves may be partially or fully involved in the gastroprotective mechanisms of FRG-8813.

Topics: Acetamides; Animals; Anti-Ulcer Agents; Drug Interactions; Gastric Mucosa; Gastrointestinal Motility; Histamine H2 Antagonists; Male; Omeprazole; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley; Stomach Ulcer

The present study was conducted to investigate the histamine H2-receptor antagonistic property of FRG-8813 by using isolated guinea pig right atria, gastric cells and cerebral cortex preparations. FRG-8813 inhibited the histamine-induced positive chronotropic response of the right atria and shifted the concentration-response curve of histamine to the right with suppression of the maximal response. Although the inhibitory effect of FRG-8813 was enhanced in a time-dependent manner and long-lasting, the antagonism was reversible. The potency of FRG-8813 was 2 times and 50 times greater than those of famotidine and cimetidine, respectively. FRG-8813 decreased the histamine-induced [14C]aminopyrine accumulation in gastric cells. Schild plot analysis showed that the slopes of FRG-8813, famotidine and cimetidine were 1.56, 1.40 and 1.07, respectively, suggesting that the mode of the antagonism of FRG-8813 is also unsurmountable in gastric cells. The lack of effect on dbcAMP- and bethanechol-induced [14C]aminopyrine accumulations indicated the selectivity of FRG-8813 for histamine H2-receptor. As in the right atria, the potency of H2-antagonism was 1.5 times and 40 times greater than those of famotidine and cimetidine, respectively. In the [3H]tiotidine binding study of the cerebral cortex preparation, the Ki values showed that the affinity of FRG-8813 was 2 times and 80 times more potent than those of famotidine and cimetidine, respectively. In conclusion, FRG-8813 is an unsurmountable and selective histamine H2-receptor antagonist with 2 times greater potency than famotidine. The antagonistic activity is reversible in spite of the time-dependent increase of the antagonism.

Topics: Acetamides; Aminopyrine; Animals; Cerebral Cortex; Cimetidine; Dose-Response Relationship, Drug; Gastric Mucosa; Guinea Pigs; Histamine H2 Antagonists; In Vitro Techniques; Male; Myocardial Contraction; Piperidines; Pyridines; Stimulation, Chemical; Time Factors

We examined the effect of FRG-8813, a new histamine H2-receptor antagonist, on 1% NH3-induced gastric mucosal lesions and basal gastric mucus production in rats. The effect of FRG-8813 (10 mg/kg) given orally was investigated macroscopically and histochemically compared with that of 16,16-dimethyl prostaglandin E2 (dmPGE2, 2 micrograms/kg) or capsaicin (Cap, 10 mg/kg) in the fundic gland area. FRG-8813, dmPGE2 and capsaicin inhibited the NH3-induced mucosal lesions, and stimulated the mucus secretion 5 min after the administration. Chemical deafferentation abolished the gastroprotective effect of FRG-8813 or Cap and attenuated the increase by FRG-8813, dmPGE2 or Cap in mucus secretion seen after 5 min. These results suggest that FRG-8813 exerts its effect on gastric mucus production partially through the capsaicin-sensitive afferent nerves, like the mechanism involved in gastroprotection, and that the increase in mucus production by FRG-8813 is at least in part responsible for the gastroprotection.

Topics: 16,16-Dimethylprostaglandin E2; Acetamides; Animals; Anti-Ulcer Agents; Capsaicin; Gastric Mucosa; Histamine H2 Antagonists; Mucus; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley

It is not presently well understood whether the histamine H2 receptor antagonist has a function other than the inhibition of gastric acid secretion, such as the effect on the gastric mucosal defence mechanism. In this paper, we report the effect of FRG-8813 (N-[4-[4-(piperidinylmethyl)pyridyl-2-oxy]-(Z)-2-butenyl]-2- (furfurylsulfinyl) acetamide), a new histamine H2 receptor antagonist, on the rat gastric mucin content with or without 0.15N HCl-ethanol (60 %)-induced gastric damage. The prior administration of FRG-8813 significantly inhibited the occurrence of macroscopically observable hemorrhagic lesions induced by the acidified ethanol treatment. Using a newly developed biochemical method, the mucin content of the deep corpus and antral mucosa of the acidified ethanol-treated animals was significantly reduced to 50% and 32% of the control, respectively. These reductions were inhibited by the pretreatment with FRG-8813. Total mucin content in the entire stomach recovered to about 80% of the control value after pretreatment with FRG-8813. A single oral administration of FRG-8813 (30 mg/kg) caused no significant change in the total mucin content, but mucin in the adherent mucus gel layer selectively and significantly increased to 250% of the control. These results suggest that FRG-8813 not only inhibits acid secretion but may also affect the gastric mucosal defensive mechanism as well.

Topics: Acetamides; Analysis of Variance; Animals; Ethanol; Gastric Mucins; Gastric Mucosa; Histamine H2 Antagonists; Male; Piperidines; Premedication; Pyridines; Rats; Rats, Wistar; Stomach Ulcer

We examined the effects of FRG-8813, a new histamine H2-receptor antagonist with potent antisecretory activity, on gastric mucus in male SD rats (7w). In this study, the effects of FRG-8813 (1, 3, 10 mg/kg), given orally twice a day for 7 days, were investigated by histochemical and biochemical methods in comparison with those of cimetidine (CM, 30 mg/kg) and famotidine (FM, 1 mg/kg) in the fundic gland area (F. area) and pyloric gland area (P. area). In the histochemical study by alcian blue (pH 2.5)-PAS (AB-PAS) or high iron diamine-alcian blue (HID-AB) staining, the CM group showed a significant decrease in PAS and tended to show decreases in HID-AB positive mucus and mucous gel layer in the F. area; the FM group also showed a decrease in AB positive mucus in the P. area. On the other hand, the AB-PAS and HID-AB positive mucus of the FRG-8813 group were not affected. In the biochemical study, FRG-8813 increased the gastric mucosal hexose, hexosamine and sialic acid composing the mucus in a dose-dependent manner in the F. area. These results suggest that FRG-8813 does not cause a decrease in gastric mucus, unlike CM or FM, and it may be able to promote mucus secretion through increasing the mucous component in the F. area.

Topics: Acetamides; Administration, Oral; Animals; Cimetidine; Dose-Response Relationship, Drug; Famotidine; Gastric Mucosa; Hexoses; Histamine H2 Antagonists; Male; Mucus; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley

FRG-8813, a new histamine H2 receptor antagonist, was examined for antisecretory effects and compared with famotidine and cimetidine in rats and dogs. In pylorus-ligated and lumen-perfused rats, FRG-8813 given i.v. reduced basal gastric acid secretion and the acid secretion evoked by histamine, tetragastrin, bethanechol, and 2-deoxy-D-glucose in a dose-dependent manner. The i.v. antisecretory activity of FRG-8813 was equivalent to or slightly less than that of famotidine and the intraduodenal (i.d.) activity was greater than that of cimetidine. The duration of action of FRG-8813 was substantially longer than that of farmotidine and cimetidine for both i.v. and i.d. routes. The i.v. ED40 values for the histamine- and tetragastrin-evoked responses and the i.v. ED30 value for the bethanechol-evoked response were 0.15, 0.09 and 0.43 mg2kg, respectively. In Heidenhain pouch dogs, when the three H2 antagonists were given i.v. or orally, the relative antisecretory potency of the compounds was similar to that in rats. The long-lasting antisecretory effect of FRG-8813 was also observed, and the i.v. ED50 values for histamine-, tetragastrin- and bethanechol-evoked responses were 0.1, 0.24 and 1.0 mg/kg, respectively. Comparison of the parenteral and enteral potencies indicated that FRG-8813 has a lower bioavailability than famotidine and cimetidine in rats and dogs. These data suggest that FRG-8813 has a potent and long-lasting antisecretory effect with a far greater potency than cimetidine and with a slightly lower potency than famotidine.

Topics: Acetamides; Animals; Cimetidine; Dogs; Famotidine; Gastric Acid; Gastric Mucosa; Histamine; Histamine Agonists; Histamine H2 Antagonists; In Vitro Techniques; Ligation; Male; Perfusion; Piperidines; Pyridines; Rats; Rats, Sprague-Dawley

We examined the anti-ulcer effects of FRG-8813, a new type histamine H2-receptor antagonist, on various experimental gastric and duodenal lesions in rats. FRG-8813, administered orally, inhibited the formation of lesions dose-dependently in experimental models with the exception of the Shay ulcer model. The anti-ulcer potency of FRG-8813 was 4 approximately 10 times greater than that of cimetidine when the ED50 values of both compounds were compared. Famotidine and cimetidine inhibited lesion formation at higher doses than the anti-secretory doses. The anti-ulcer action of FRG-8813, however, appeared at even lower doses than those of anti-secretory action. These results suggest that FRG-8813 is able to prevent lesion formation with anti-secretory action plus other mechanisms unlike typical histamine H2-receptor antagonists.

Topics: Acetamides; Animals; Disease Models, Animal; Dose-Response Relationship, Drug; Duodenal Ulcer; Gastric Acid; Histamine H2 Antagonists; Male; Piperidines; Pyridines; Rats; Rats, Wistar; Stomach Ulcer

We examined the anti-ulcer effects of FRG-8813, a new-type histamine H2-receptor antagonist, in chronic ulcer models of rats and mice (W/WV). FRG-8813, given orally twice a day for 7 days, accelerated the healing of gastric or duodenal ulcer induced by acetic acid injection or application at the non-antisecretory doses (0.3 approximately 3 mg/kg). Administration of FRG-8813 to rats with ulcers increased the amounts of mucus in the gastric mucosa. These actions of FRG-8813 were more potent than those of famotidine or cimetidine. In W/WV mice, several ulcers spontaneously developed on gastric mucosa during the 8 weeks after the birth. The ulcers were aggravated by several unknown factors after the ulcer generation in W/WV mice. The aggravation of ulcers was inhibited by the 4-week administration of FRG-8813 with diet at the dose of 1 or 10 mg/kg/day, but was not inhibited by cimetidine at the dose of 100 mg/kg/day. From these results, we suggest that FRG-8813 is able to accelerate the healing of ulcers by antisecretory plus increasing actions on the integrity of the gastric mucosal defense mechanisms; therefore FRG-8813 is expected to be a useful drug for the treatment of gastric or duodenal ulcers in humans.

Topics: Acetamides; Animals; Chronic Disease; Disease Models, Animal; Duodenal Ulcer; Gastric Acid; Histamine H2 Antagonists; Male; Mice; Piperidines; Pyridines; Rats; Rats, Wistar; Stomach Ulcer