geranylgeranylacetone and Acute-Disease

The protective effect of teprenone, an anti-ulcer drug, against acute gastric mucosal lesions was examined in rats with a single intraperitoneal injection of compound 48/80 (0.75 mg/kg). Teprenone (50, 100, or 200 mg/kg) was orally administered 0.5 h before compound 48/80 treatment. Administered teprenone prevented gastric mucosal lesion development found at 3 h after compound 48/80 treatment dose-dependently, although no dose of teprenone affected the decreased gastric mucosal blood flow and increased serum serotonin and histamine concentrations found at 3 h after the treatment. Increases in the activities of myeloperoxdiase (an index of neutrophil infiltration) and xanthine oxidase and the content of thiobarbituric acid reactive substances (an index of lipid peroxidation) and decreases in the contents of hexosamine (a marker of gastric mucus) and adherent mucus occurred in gastric mucosal tissues at 3 h after compound 48/80 treatment. Administered teprenone dose-dependently attenuated all these changes found at 3 h after compound 48/80 treatment. These results indicate that orally administered teprenone protects against compound 48/80-induced acute gastric mucosal lesions in rats possibly through its stimulatory action on gastric mucus synthesis and secretion and its inhibitory action on neutrophil infiltration and enhanced lipid peroxidation in the gastric mucosal tissue.

Topics: Acute Disease; Animals; Cell Degranulation; Diterpenes; Dose-Response Relationship, Drug; Gastric Mucosa; Male; Mast Cells; p-Methoxy-N-methylphenethylamine; Rats; Rats, Wistar; Stomach Ulcer

The effect of rebamipide (2-(4-chlorobenzoylamino)-3-[2(1H)-quinolinon-4-yl] propionic acid, CAS 11911-87-6) in preventing acute gastritis was examined in rats by stomach perfusion. Teprenone (CAS 6809-52-5), cimetidine (CAS 51481-61-9) and omeprazole (CAS 73590-58-6) were used as control drugs. Severe gastric hemorrhage was observed in conscious restrained rats, 1 h after treatment with indometacin (20 mg/kg i.p.). Pretreatment with rebamipide (3, 10 or 30 mg/kg s.c.) suppressed the hemorrhage induced by indometacin plus restraint stress, being more effective than teprenone or cimetidine. Pretreatment with omeprazole (30 mg/kg s.c.) did not suppress the gastric hemorrhage. Superoxide dismutase (30,000 U/kg s.c.) significantly decreased the hemorrhage. Anti-rat PMN (polymorphonuclear leukocytes), 1 ml/kg i.v., which caused depletion of circulating neutrophils, also suppressed the hemorrhage induced by indometacin plus restraint stress. Thus reactive oxygen species derived from neutrophils may play a role in the occurrence of the hemorrhage during acute gastritis induced by indometacin with restraint stress.

Topics: Acute Disease; Alanine; Animals; Anti-Inflammatory Agents, Non-Steroidal; Anti-Ulcer Agents; Catalase; Cimetidine; Diterpenes; Gastritis; Gastrointestinal Hemorrhage; Indomethacin; Leukocyte Count; Male; Neutrophils; Omeprazole; Perfusion; Quinolones; Rats; Rats, Wistar; Restraint, Physical; Stress, Psychological; Superoxide Dismutase

To evaluate the effects of teprenone on acute gastritis, its inhibitory effects on gastric mucosal damage were compared to that of gefarnate in taurocholate/hydrochloric acid-induced acute gastric mucosal lesions in rats. After oral administration of 160 mM taurocholic acid and 250 mM hydrochloric acid, hemorrhage and erosion were macroscopically observed in the gastric mucosal surface layer. Edema in the submucosal tissue and decreased PAS staining in the mucosa were histomorphologically observed. Concerning macroscopic findings, pretreatment with teprenone at a dose of 50 mg/kg or more significantly reduced pathological changes in the mucosa of the fundic glandular area. However, gefarnate slightly inhibited these changes in at a dose of 50 mg/kg and significantly inhibited them at a dose of 200 mg/kg. With regards to histomorphological findings in the fundic glandular area, teprenone slightly inhibited erosion at a dose of 50 mg/kg, and it significantly and slightly inhibited the decrease in PAS staining in this area at doses of 50 and 200 mg/kg, respectively. Gefarnate at doses of 50 and 200 mg/kg showed significant inhibition of decreased PAS staining in the fundic glandular area. In the pyloric mucosa, decreased PAS staining was slightly inhibited by teprenone at both doses but not by gefarnate at either dose. The differences between teprenone and gefarnate observed in this model appear to be due to their differences in mucus production ability. These results suggest that teprenone was more effective than gefarnate for the treatment of gastritis.

Topics: Acute Disease; Animals; Anti-Ulcer Agents; Disease Models, Animal; Diterpenes; Dose-Response Relationship, Drug; Gastric Mucosa; Gastritis; Gefarnate; Hydrochloric Acid; Male; Mucus; Rats; Rats, Wistar; Taurocholic Acid

The effects of tetraprenylacetone (TPN), an acyclic polyisoprenoid with antiulcer actions, on pancreatic exocrine secretion, and its preventive and therapeutic effects on acute pancreatitis in two experimental models were studied in rats. Intraduodenal administration of TPN (0, 100, 200, and 400 mg/kg/h) caused dose-dependent increases in pancreatic juice and bicarbonate output without increasing protein output and plasma cholecystokinin (CCK) concentrations. TPN-stimulated pancreatic exocrine secretion was completely abolished by antisecretin serum but it was not by CCK receptor antagonist loxiglumide (50 mg/kg/h). In acute pancreatitis induced by four subcutaneous injections of 20 micrograms/kg cerulein at hourly intervals over, 3 h, TPN (400 mg/kg) given by an oral route either 1 h before the first cerulein injection or immediately after the last injection significantly reduced the increases in serum amylase and lipase activities and pancreatic wet wt. Pretreatment with TPN caused histologic improvements, whereas posttreatment failed to ameliorate histologic alterations. In severe type of acute pancreatitis induced by retrograde intraductal injection of 1.0 mL/kg of 4% sodium taurocholate, TPN exerted no apparent beneficial effects on biochemical and histologic alterations of acute pancreatitis. It is concluded that TPN given by an oral route stimulates pancreatic exocrine secretion through an increase in endogenous secretin release and causes beneficial effects on the experimental model of mild acute pancreatitis in rats.

Topics: Acute Disease; Amylases; Animals; Anti-Ulcer Agents; Disease Models, Animal; Diterpenes; Lipase; Male; Pancreas; Pancreatic Juice; Pancreatitis; Rats; Rats, Wistar