sincalide and Disease-Models--Animal

This study aimed at exploring the expression level of LTBP1 in the mouse model of epilepsy. The mechanism of LTBP1 in epileptic cerebral neural stem cells was deeply investigated to control the occurrence of epilepsy with neuroprotection.. qRT-PCR was conducted for the expression levels of LTBP1 in clinical human epileptic tissues and neural stem cells, as well as normal cerebral tissues and neural stem cells. The mouse model of postischemic stroke epilepsy (PSE) was established by the middle cerebral artery occlusion (MCAO). Then, qRT-PCR was conducted again for the expression levels of LTBP1 in mouse epileptic tissues and neural stem cells as well as normal cerebral tissues and neural stem cells. The activation and inhibitory vectors of LTBP1 were constructed to detect the effects of LTBP1 on the proliferation of cerebral neural stem cells in the PSE model combined with CCK-8. Finally, Western blot was conducted for the specific mechanism of LTBP1 affecting the development of epileptic cells.. Racine score and epilepsy index of 15 mice showed epilepsy symptoms after the determination with MCAO, showing a successful establishment of the PSE model. LTBP1 expression in both diseased epileptic tissues and cells was higher than that in normal clinical epileptic tissues and cells. Meanwhile, qRT-PCR showed higher LTBP1 expression in both mouse epileptic tissues and their neural stem cells compared to that in normal tissues and cells. CCK-8 showed that the activation of LTBP1 stimulated the increased proliferative capacity of epileptic cells, while the inhibition of LTBP1 expression controlled the proliferation of epileptic cells. Western blot showed an elevated expression of TGFβ/SMAD signaling pathway-associated protein SMAD1/5/8 after activating LTBP1. The expression of molecular MMP-13 associated with the occurrence of inflammation was also activated.. LTBP1 can affect the changes in inflammation-related pathways by activating the TGFβ/SMAD signaling pathway and stimulate the development of epilepsy, and the inhibition of LTBP1 expression can control the occurrence of epilepsy with neuroprotection.

Topics: Animals; Cerebral Cortex; Disease Models, Animal; Epilepsy; Gene Expression; Humans; Inflammation; Latent TGF-beta Binding Proteins; Mice; Neuroprotection; Sincalide; Stroke; Transforming Growth Factor beta

Myocardial infarction (MI) increases myocardial fibrosis (MF) and subsequent cardiac remodeling. Cholecystokinin octapeptide (CCK-8) is expressed in cardiomyocytes and plays an important role in cardiovascular regulation. In this study, we intend to use a rat model of myocardial infarction to evaluate the effects of CCK-8 on myocardial fibrosis and cardiac remodeling.. Male Sprague-Dawley rats were separated into 3 groups: sham operation, MI + NaCl, and MI + CCK-8. All rats were subjected to left coronary artery ligation to induce MI or sham operation and then treated with CCK-8 or saline for 28 days. After 4 weeks, echocardiography was performed to assess cardiac function and myocardial fibrosis was evaluated using H&E and Masson's Trichrome-stained sections. The levels of BNP, CCK-8 in the plasma of all rats were detected by ELISA; RNA sequencing (RNA-seq) analysis was also adapted to detect differentially expressed genes in myocardial tissues of each group. Myocardial expression of fibrosis markers was analyzed by western blotting, immunohistochemistry and qRT-PCR.. CCK-8 was demonstrated to improve left ventricular function and results of H&E staining, Masson's trichrome staining, immunohistochemistry and western blotting showed that CCK-8 attenuated MF. Gene expression profiles of the left ventricles were analysed by RNA-seq and validated by qRT-PCR. Cardiac fibrosis genes were downregulated by CCK-8 in the left ventricle.. CCK-8 can alleviate fibrosis in the noninfarcted regions and delay the left ventricular remodeling and the progress of heart failure in a MI rat model.

Topics: Animals; Cardiomyopathies; Disease Models, Animal; Echocardiography; Gene Expression Regulation; Heart Ventricles; Male; Myocardial Infarction; Myocytes, Cardiac; Natriuretic Peptide, Brain; Rats; Rats, Sprague-Dawley; RNA-Seq; Sincalide; Ventricular Remodeling

Dexamethasone (Dex), a widely prescribed anti-inflammatory drug, was reported to induce liver enlargement (hepatomegaly) in clinical practice and in animal models. However, the underlying mechanisms are not elucidated. Dex is a known activator of pregnane X receptor (PXR). Yes-associated protein (YAP) has been implicated in chemically induced liver enlargement. Here, the roles of PXR and YAP pathways were investigated in Dex-induced hepatomegaly. Upregulation of PXR downstream proteins, including cytochrome P450 (CYP) 3A11, 2B10, and organic anion transporter polypeptide 2 (OATP2), indicated PXR signaling was activated after high dose of Dex (50 mg/kg, i.p.), and Dex at 100 μM activated PXR in the dual-luciferase reporter gene assay. Dex also increased the expression of total YAP, nuclear YAP, and YAP downstream proteins, including connective tissue growth factor and cysteine-rich angiogenic inducer 61, indicating activation of the YAP pathway. Furthermore, nuclear translocation of YAP was promoted by activation of PXR. However, hepatocyte proliferation was inhibited with significant decrease in the expression of proliferation-related proteins cyclin D1 and proliferating cell nuclear antigen as well as other regulatory factors, such as forkhead box protein M1, c-MYC, and epidermal growth factor receptor. The inhibitory effect of Dex on hepatocyte proliferation was likely due to its anti-inflammation effect of suppression of inflammation factors. β-catenin staining revealed enlarged hepatocytes, which were mostly attributable to the accumulation of lipids, such as triglycerides. In summary, high-dose Dex increased liver size accompanied by enlarged hepatocytes, and this was due to the activation of PXR/YAP and their effects on lipid accumulation but not hepatocyte proliferation. These findings provide new insights for understanding the mechanism of Dex-induced hepatomegaly. SIGNIFICANCE STATEMENT: This study identified the roles of pregnane X receptor (PXR) and yes-associated protein (YAP) pathways in dexamethasone (Dex)-induced hepatomegaly. Dex induced PXR/YAP activation, enlarged hepatocytes, and promoted liver enlargement with lipid accumulation, such as triglycerides. However, hepatocyte proliferation was inhibited by the anti-inflammatory effect of Dex. These findings provide new insights for understanding the mechanism of Dex-induced hepatomegaly.

Topics: Adaptor Proteins, Signal Transducing; Animals; Cell Proliferation; Dexamethasone; Disease Models, Animal; HEK293 Cells; Hep G2 Cells; Hepatocytes; Hepatomegaly; Humans; Lipid Metabolism; Liver; Male; Mice; Pregnane X Receptor; Sincalide; Transcription Factors; Triglycerides; YAP-Signaling Proteins

Acute pancreatitis is an inflammatory process of the pancreas and a leading cause of hospitalization amongst gastrointestinal disorders. Previously, cholecystokinin (CCK) has been described to play a role in regeneration of pancreas. The aim of this study was to analyse the function of cholecystokinin octapeptide (CCK-8) during induced pancreatitis in an animal model.. Overall acute pancreatitis was induced in 38 pigs. After the induction of acute pancreatitis, half of the animals were treated with CCK-8. Intraoperative clinical data, postoperative blood parameters, 'Porcine Well-being' (PWB) and fitness score and post-mortal histopathological data were analysed.. At baseline, physiologically parameters of the pigs of both groups were comparable. No differences were observed regarding the overall survival of animals (p = 0.97). Postoperative PWB score were significantly enhanced in animals treated with CCK-8 as compared to the control group (p = 0.029). Moreover, histopathological analysis of the pancreatic tissue revealed that acinar necrosis and edema were significant reduced in the CCK-8 group in comparison to the control group (p = 0.016 and p = 0.019).. In conclusion, we found that CCK-8 treatment reduces acinar necrosis and edema of pancreatic tissue after induction of an acute pancreatitis in pigs.

Topics: Animals; Cholecystokinin; Disease Models, Animal; Necrosis; Pancreas; Pancreatitis; Peptide Fragments; Swine

Pain is associated with negative emotions such as anxiety, but the underlying neurocircuitry and modulators of the association of pain and anxiety remain unclear. The neuropeptide cholecystokinin (CCK) has both pronociceptive and anxiogenic properties, so we explored the role of CCK in anxiety and nociception in the central amygdala (CeA), a key area in control of emotions and descending pain pathways. Local infusion of CCK into the CeA of control rats increased anxiety, as measured in the light-dark box test, but had no effect on mechanical sensitivity. By contrast, intra-CeA CCK infusion 4 days after Complete Freund's Adjuvant (CFA) injection into the hindpaw resulted in analgesia, but also in loss of its anxiogenic capacity. Inflammatory conditions induced changes in the CeA CCK signaling system with an increase of CCK immunoreactivity and a decrease in CCK1, but not CCK2, receptor mRNA. In CFA rats, patch-clamp experiments revealed that CCK infusion increased CeA neuron excitability. It also partially blocked the discharge of wide dynamic range neurons in the dorsal spinal cord. These effects of CCK on CeA and spinal neurons in CFA rats were mimicked by the specific CCK2 receptor agonist, gastrin. This analgesic effect was likely mediated by identified CeA neurons projecting to the periaqueductal gray matter that express CCK receptors. Together, our data demonstrate that intra-CeA CCK infusion activated a descending CCK2 receptor-dependent pathway that inhibited spinal neuron discharge. Thus, persistent pain induces a functional switch to a newly identified analgesic capacity of CCK in the amygdala, indicating central emotion-related circuit controls pain transmission in spinal cord.

Topics: Amygdala; Animals; Cholecystokinin; Dark Adaptation; Disease Models, Animal; Exploratory Behavior; Freund's Adjuvant; Gastrins; Glutamate Decarboxylase; Inflammation; Male; Neurons; Nociception; Pain; Pain Threshold; Periaqueductal Gray; Rats; Rats, Sprague-Dawley; Receptor, Cholecystokinin B; Signal Transduction; Sincalide; Tetragastrin

HA modified by bisphosphonate (BP) (HA-BP) was synthesized by chemical reaction and possessed promising properties such as self-healing, injection ability, and strong adhesion. The main aim of this study was to confirm its role in promoting osteogenic differentiation in vitro and bone regeneration in vivo.. The cell biocompatibility of this material was determined using the CCK-8 assay. Alkaline phosphatase (ALP), osteocalcin (OT), vascular endothelial growth factor (VEGF), and collagen I were assessed by quantitative real-time polymerase chain reaction (Q-PCR) in the treated group. The number and density of calcium nodules and ALP were evaluated by Alizarin Red staining and ALP staining. We have successfully developed an animal model simulating osteonecrosis of the femoral head (ONFH). Utilizing this animal model, the impact of HA-BP/CaP on bone formation was assessed. The amount of bone regeneration at 1 and 2 months after HA-BP/CaP injection was estimated by micro-computed tomography (micro-CT) analysis and H&E, collagen I, and periostin staining.. The number of cells gradually increased in the experimental group over time and was close to that of the blank control group. ALP, collagen I, and VEGF expression was significantly higher in the experimental group than in the blank group (VEGF, ALP, both **p < 0.01; collagen I, ***p<0.001). In addition, the number and density of calcium nodules and ALP was clearly greater in the material group than in the control group. The quantification analysis showed that the mineral contents of regenerated bone at 1 and 2 months after HA-BP/CaP injection were significantly greater than those in the control group, according to micro-CT evaluation (**p<0.01). The amount of organic components in the HA-BP/CaP group was greater than that in the control group after decalcification and H&E staining. In addition, collagen I and periostin staining further confirmed the results of H&E staining.. This material can boost proliferation and osteogenic differentiation of MC3T3-E1 cells in vitro. It can intensely accelerate bone regeneration in vivo, which is a promising strategy for tissue engineering.

Topics: 3T3 Cells; Animals; Biocompatible Materials; Bone Regeneration; Calcium Phosphates; Cell Differentiation; Cell Proliferation; Cholecystokinin; Diphosphonates; Disease Models, Animal; Female; Femur Head Necrosis; Humans; Hyaluronic Acid; Hydrogels; Materials Testing; Mice; Osteogenesis; Peptide Fragments; Rabbits; Tissue Engineering; X-Ray Microtomography

Evodiamine (EVO) has been reported to play an important role in regulating gastrointestinal motility, but the evidence is insufficient, and the mechanism remains unknown. The aim of this study is to investigate the possible role of EVO in stress-induced colonic hypermotility and the potential mechanisms via both in vivo and in vitro investigations.. Male Sprague-Dawley rats were exposed to water avoidance stress (WAS) for 1 h or sham WAS daily for 10 consecutive days to construct the rat model. The colonic contractile activity was studied in an organ bath system. The serum CCK-8 level was detected using an enzyme immunoassay kit, and gastrointestinal transit was detected by intragastric administration of India ink.. WAS induced gastrointestinal hypermotility in male rats. EVO significantly inhibited the contractile activity of colonic muscle strips; this effect was not blocked by TTX and the CCK. EVO can reverse stress-induced gastrointestinal hypermotility. This effect may partially occur as a result of promoting the release of CCK and then activating the CCK

Topics: Animals; Avoidance Learning; Biomarkers; Disease Models, Animal; Gastrointestinal Motility; Male; Quinazolines; Rats; Rats, Sprague-Dawley; Receptors, Cholecystokinin; Sincalide; Stress, Psychological

Excessive extracellular matrix degradation and chondrocyte apoptosis are the pathological features of osteoarthritis (OA). The ability of flavonoid compounds isolated from Chinese hawthorn leaves to exert protective effects on several diseases, via inhibition of oxidative stress and inflammation, has been demonstrated in several studies. This study explored the effects of vitexin on chondrocytes, and the underlying mechanisms thereof. Vitexin, an active ingredient in hawthorn leaf extracts, was shown to exert protective effects on chondrocytes, by inhibiting the expression of GRP78 and PDI, and an apoptotic protein (CHOP) induced by interleukin-1β. It also modulated thapsigargin-induced upregulation of GRP78 and PDI and subsequently an apoptotic protein (CHOP). Among rat chondrocytes, both the ER stress-activated nuclear factor kappa B (NF-κB) pathway and the induced expression of inflammatory cytokines (IL-6 and TNF-α) were significantly inhibited by vitexin. Finally, vitexin attenuated the progression of OA in vivo in rats. Taken together, all data demonstrate the relationship of ER stress and inflammation in the progression of OA, the ability of vitexin to protect chondrocytes and thus its therapeutic potential in patients with OA.

Topics: Animals; Apigenin; Apoptosis; Cartilage; Caspase 3; Cell Survival; Chondrocytes; Disease Models, Animal; Endoplasmic Reticulum Stress; Heat-Shock Proteins; Inflammation; Interleukin-1beta; Male; NF-kappa B; Osteoarthritis; Rats; Rats, Sprague-Dawley; Sincalide; Thapsigargin; Transcription Factor CHOP; Tumor Necrosis Factor-alpha; Up-Regulation

Cholecystokinin (CCK) is one of the main neurohormone peptide systems in the brain, and a major anxiogenic mediator. The periaqueductal gray (PAG) is a key midbrain structure for defensive behaviors, which could include anxiety, fear, or even panic. The CCK system has wide distribution in the PAG, where the dorsolateral region (DL) participates in active defensive behavior and the ventrolateral region (VL) in passive defensive behavior. The aim of this study was to assess the effect of CCK-8 microinjection into DL-PAG or VL-PAG on anxiety-like behavior through two tests: elevated plus maze (EPM) and defensive burying behavior (DBB). CCK-8 (0.5 and 1.0 μg/0.5 μL) presently microinjected into the DL-PAG produced an anxiogenic-like effect on the EPM evidenced by decreasing the time spent/number of entries in open arms compared to vehicle group. Additionally, the latency to burying decreased and burying time increased on the DBB test. Contrarily, CCK-8 microinjected into the VL-PAG resulted in greater open-arm time and more open-arm entries compared to the vehicle-microinjected group. The results on the DBB test confirmed an anxiolytic-like response of CCK-8 into the VL-PAG. In conclusion, CCK-8 microinjected into DL-PAG produced anxiety-like behavior on EPM, and for first time reported on DBB. Contrarily, CCK-8 microinjected into the VL-PAG reduced anxiety-like behavior also for first time reported using both behavioral models EPM and DBB.

Topics: Animals; Anti-Anxiety Agents; Anxiety; Behavior, Animal; Cholecystokinin; Disease Models, Animal; Escape Reaction; Fear; Injections, Intraventricular; Male; Maze Learning; Microinjections; Periaqueductal Gray; Rats; Rats, Wistar; Sincalide

Inflammatory reaction plays a crucial role in cerebral ischemia reperfusion (IR) injury. It has been shown that activated microglia long-term existed in cerebral ischemia and induced second injury. Therefore, we hypothesize that prepared phosphatidylserine (PS)-modified microbubbles (PS-MBs) combined with ultrasound-targeted microbubble destruction (UTMD) can safely open the blood-brain barrier (BBB) and target activated microglia for inflammatory area in the later stage of ischemia reperfusion.. To verify our hypothesis, rat model of IR was established, then the change of activated microglia/macrophage (M/M) and permeability of BBB at 1, 7, 14, and 21 days could be clearly observed post IR. And the activated M/M still can be observed during the whole experiment.. The Evans blue extravasation of BBB gradually declined from day 1 to day 21. Compared to the control group, microbubbles containing PS were taken up more by activated M/M (approximately twofold) both in vitro and in vivo.. PS-MBs combined with ultrasound (US) exposure could safely open BBB, and the resulting PS nanoparticles (PS-NPs) could further target activated M/M in the neuroinflammation.

Topics: Animals; Blood-Brain Barrier; Cerebral Infarction; Disease Models, Animal; Dose-Response Relationship, Drug; Encephalitis; Hypoxia-Ischemia, Brain; Macrophages; Magnetic Resonance Imaging; Male; Microbubbles; Microglia; Permeability; Phosphatidylserines; Rats; Rats, Sprague-Dawley; Sincalide; Time Factors; Ultrasonography

A series of twenty two (E)-N-cinnamoyl aminoalkanols derivatives monosubstituted in phenyl ring with 4-Cl, 4-CH

Topics: Amino Alcohols; Animals; Anticonvulsants; Crystallography, X-Ray; Disease Models, Animal; Dose-Response Relationship, Drug; Electroshock; Mice; Models, Molecular; Molecular Structure; Rats; Seizures; Structure-Activity Relationship

The Sonic hedgehog (Shh) signaling pathway is recapitulated in response to ischemic injury. Here, we investigated the clinical implications of Shh protein in the ischemic stroke and explored the underlying mechanism. Intracerebroventricular injection of Shh, Cyclopamine, or anti-vascular endothelial growth factor (VEGF) was performed immediately after permanent middle cerebral artery occlusion (pMCAO) surgery and lasted for 7days (d). Phosphate-buffered saline (PBS) was used as control. Neurological deficits and infarct volume were examined 7d after pMCAO. Microvascular density with fluorescein-iso-thiocyanate (FITC) assay and double staining with CD31 and Ki-67 was measured at 7d. To observe in vitro angiogenesis, rat brain microvascular endothelial cells (RBMECs) were incubated under oxygen glucose deprivation (OGD) for 6h (h) and treated with Shh/anti-VEGF. We found that (1) Shh improved neurological scores and reduced infarct volume, which was blocked by Cyclopamine, (2) Shh improved the microvascular density and promoted angiogenesis and neuron survival in the ischemic boundary zone, (3) Shh enhanced VEGF expression and VEGF antibody could reverse angiogenic and protective effect of Shh in vivo and in vitro. These data demonstrate that the administration of Shh protein could protect brain from ischemic injury, in part by promoting angiogenic repair.

Topics: Angiogenesis Inducing Agents; Animals; Brain; Brain Infarction; Cell Movement; Cells, Cultured; Cholecystokinin; Disease Models, Animal; Drug Delivery Systems; Dyneins; Endothelial Cells; Hedgehog Proteins; Male; Neovascularization, Pathologic; Patched-1 Receptor; Peptide Fragments; Rats; Rats, Sprague-Dawley; Signal Transduction; Stroke; Vascular Endothelial Growth Factor A

The sites of action regulating meal size (MS) and intermeal interval (IMI) length by glucagon like peptide-1 (7-36) (GLP-1 (7-36)) and cholecystokinin-8 (CCK-8) reside in the areas supplied by the two major branches of the abdominal aorta, celiac and cranial mesenteric arteries. We hypothesized that infusing GLP-1 near those sites reduces body weight (BW) and adding CCK-8 to this infusion enhances the reduction. Here, we measured BW in diet-induced obese (DIO) male rats maintained and tested on normal rat chow and infused with saline, GLP-1 (0.5nmol/kg) and GLP-1+CCK-8 (0.5nmol/kg each) in the aorta once daily for 21days. We found that GLP-1 and GLP-1+CCK-8 decrease BW relative to saline vehicle and GLP-1+CCK-8 reduced it more than GLP-1 alone. Reduction of BW by GLP-1 alone was accompanied by decreased 24-h food intake, first MS, duration of first meal and number of meals, and an increase in latency to first meal. Reduction of BW by the combination of the peptides was accompanied by decrease 24-h food intake, first MS, duration of first meal and number of meals, and increase in the IMI length, satiety ratio and latency to first meal. In conclusion, GLP-1 reduces BW and CCK-8 enhances this reduction if the peptides are given near their sites of action.

Topics: Animals; Anti-Obesity Agents; Aorta; Cholecystokinin; Diet, High-Fat; Disease Models, Animal; Drug Therapy, Combination; Eating; Feeding Behavior; Glucagon-Like Peptide 1; Male; Obesity; Peptide Fragments; Rats, Sprague-Dawley; Satiation; Time Factors; Weight Loss

Pyrroloquinoline quinone is an anionic, water-soluble compound with antioxidant characteristic. The role of pyrroloquinoline quinone in pharmacology and nutrition has attracted wide attention of researchers. Although a few experiments have confirmed that pyrroloquinoline quinone plays an obvious effective role in neuroprotection. There are few reports about the effect of pyrroloquinoline quinone on traumatic brain injury. Traumatic brain injury is one of the leading causes for adult disability and death. So far, there are no effective treatment methods for the injury because of its complex pathophysiology.. In the present study, a model of traumatic brain injury in rat was established to study the role of pyrroloquinoline quinone in central nervous system injury.. The results showed that the protein expression of cleaved-Caspase 3/Caspase 3 increased after traumatic brain injury and the expression decreased by treatment with 2mM pyrroloquinoline quinone. Terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) staining displayed that the TUNEL positive signals were up-regulated after traumatic brain injury and were down-regulated after treatment with 2mM pyrroloquinoline quinone. The protein expression of LC3II/LC3I or lysosome-associated membrane protein 2(LAMP2) was elevated after traumatic brain injury and reduced after administration with 2mM pyrroloquinoline quinone. Transmission electron microscopy showed that the number of autophagosomes increased markedly after traumatic brain injury and decreased on administration of 2mM pyrroloquinoline quinone. Electroencephalogram indicated that pyrroloquinoline quinone improved brain electrophysiological function after traumatic brain injury. The results of CCK-8 test showed that pyrroloquinoline quinone could increase the viability of primary astrocyte treated with Glutamate. Lactate dehydrogenase (LDH) assay demonstrated that pyrroloquinoline quinone decreased LDH content in primary astrocyte exposed to Glutamate.. Pyrroloquinoline quinone could play a neuroprotective role after traumatic brain injury in rat, which might be associated with inhibiting apoptosis and autophagy caused by traumatic brain injury.

Topics: Animals; Animals, Newborn; Apoptosis; Astrocytes; Autophagosomes; Autophagy; Brain Injuries, Traumatic; Caspase 3; Cells, Cultured; Disease Models, Animal; Glial Fibrillary Acidic Protein; Glutamic Acid; L-Lactate Dehydrogenase; Lysosomal-Associated Membrane Protein 2; Male; Microtubule-Associated Proteins; Neuroprotective Agents; Phosphopyruvate Hydratase; PQQ Cofactor; Rats; Rats, Sprague-Dawley; Sincalide

Axon development plays a pivotal role in the formation of synapse, nodes of Ranvier, and myelin sheath. Interleukin-1β (IL-1β) produced by microglia may cause myelination disturbances through suppression of oligodendrocyte progenitor cell maturation in the septic neonatal rats. Here, we explored if a microglia-derived IL-1β would disturb axon development in the corpus callosum (CC) following lipopolysaccharide (LPS) administration, and if so, whether it is associated with disorder of synapse formation in the cerebral cortex and node of Ranvier.. Sprague-Dawley rats (1-day old) in the septic model group were intraperitoneally administrated with lipopolysaccharide (1 mg/kg) and then sacrificed for detection of IL-1β, interleukin-1 receptor (IL-1R. In 1-day old septic rats, IL-1β expression was increased in microglia coupled with upregulated expression of IL-1R. The present results suggest that microglia-derived IL-1β might suppress axon development through activation of p38-MAPK signaling pathway that would contribute to formation disorder of cortical synapses and node of Ranvier following LPS exposure.

Topics: Age Factors; Animals; Animals, Newborn; Cells, Cultured; Cerebral Cortex; Disease Models, Animal; Gene Expression Regulation; Interleukin-1beta; Lipopolysaccharides; Microglia; Neonatal Sepsis; Nerve Tissue Proteins; Neurons; p38 Mitogen-Activated Protein Kinases; Rats; Rats, Sprague-Dawley; Signal Transduction; Sincalide; Synapses; Synaptophysin

Glaucoma is a progressive neurodegenerative disease, characterized by retinal ganglion cells (RGCs) and axon degeneration. The development of neuroprotective drug is required for improving the efficiency of glaucoma treatment. Eucommia ulmoides Oliv. has been used as a source of traditional medicine and as a beneficial health food. Lignans is one of the main bioactive components of Eucommia ulmoides. Here, we show that lignans protects RGCs against oxidative stress-induced injury in vitro. Moreover, lignans exerts neuroprotective effect on glaucoma-associated optic neuropathy in glaucomatous rats. Lignans treatment could improve oxidative stress response in RGCs and retinas of glaucomatous rats. Lignans plays an anti-oxidative stress role via the activation of AMPK signaling. This study provides evidence that lignans possesses protective effect on glaucoma-associated optic neuropathy. Lignans might be an alternative for the prevention and treatment of glaucomatous neurodegeneration.

Topics: Animals; Cells, Cultured; Disease Models, Animal; Dose-Response Relationship, Drug; Eucommiaceae; Fluoresceins; Gene Expression Regulation; Glaucoma; Hydrogen Peroxide; Lignans; Male; Neuroprotective Agents; Optic Nerve Diseases; Phosphopyruvate Hydratase; Rats; Rats, Wistar; Retinal Ganglion Cells; RNA, Long Noncoding; Signal Transduction; Sincalide; Tubulin

To investigate the mechanisms and effects of sphincter of Oddi (SO) motility on cholesterol gallbladder stone formation in guinea pigs.. Thirty-four adult male Hartley guinea pigs were divided randomly into two groups, the control group (n = 10) and the cholesterol gallstone group (n = 24), which was sequentially divided into four subgroups with six guinea pigs each according to time of sacrifice. The guinea pigs in the cholesterol gallstone group were fed a cholesterol lithogenic diet and sacrificed after 3, 6, 9, and 12 wk. SO manometry and recording of myoelectric activity were obtained by a multifunctional physiograph at each stage. Cholecystokinin-A receptor (CCKAR) expression levels in SO smooth muscle were detected by quantitative real-time PCR (qRT-PCR) and serum vasoactive intestinal peptide (VIP), gastrin, and cholecystokinin octapeptide (CCK-8) were detected by enzyme-linked immunosorbent assay at each stage in the process of cholesterol gallstone formation.. The gallstone formation rate was 0%, 0%, 16.7%, and 83.3% in the 3, 6, 9, and 12 wk groups, respectively. The frequency of myoelectric activity in the 9 wk group, the amplitude of myoelectric activity in the 9 and 12 wk groups, and the amplitude and the frequency of SO in the 9 wk group were all significantly decreased compared to the control group. The SO basal pressure and common bile duct pressure increased markedly in the 12 wk group, and the CCKAR expression levels increased in the 6 and 12 wk groups compared to the control group. Serum VIP was elevated significantly in the 9 and 12 wk groups and gastrin decreased significantly in the 3 and 9 wk groups. There was no difference in serum CCK-8 between the groups.. A cholesterol gallstone-causing diet can induce SO dysfunction. The increasing tension of the SO along with its decreasing activity may play an important role in cholesterol gallstone formation. Expression changes of CCKAR in SO smooth muscle and serum VIP and CCK-8 may be important causes of SO dysfunction.

Topics: Animals; Cholesterol; Disease Models, Animal; Electromyography; Enzyme-Linked Immunosorbent Assay; Gallstones; Gastrins; Guinea Pigs; Manometry; Muscle, Smooth; Real-Time Polymerase Chain Reaction; Receptor, Cholecystokinin A; Sincalide; Sphincter of Oddi; Sphincter of Oddi Dysfunction; Vasoactive Intestinal Peptide

Astilbin, a major bioactive compound extracted from Rhizoma smilacis glabrae (RSG), has been reported to possess immunosuppressive properties. Our study first evaluated the effect of astilbin on experimental autoimmune myasthenia gravis (EAMG) in Lewis rats. The results showed that astilbin could attenuate the severity of EAMG by decreasing antigen-specific autoantibodies with up-regulation of regulatory T cells and down-regulation of Th17 cells. In addition to, astilbin also reduced the efficiency of the antigen presenting cells on which the expression of MHC class II decreased. These results suggest that astilbin might be a candidate drug for immunoregulation of EAMG, and provide us new treatment ideas for human myasthenia gravis (MG).

Topics: Analysis of Variance; Animals; Anti-Inflammatory Agents; Antigens, CD; Body Weight; Cell Proliferation; Cytokines; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Flavonols; Flow Cytometry; HLA-DR alpha-Chains; Myasthenia Gravis, Autoimmune, Experimental; Rats; Rats, Inbred Lew; Sincalide; T-Lymphocytes, Regulatory; Th17 Cells

Major depressive disorder is a common and complex mental disorder with unknown etiology. GABAergic dysfunction is likely to contribute to the pathophysiology since disrupted GABAergic systems are well documented in depressed patients. Here we studied structural changes in the hippocampal GABAergic network using the chronic mild stress (CMS) model, as one of the best validated animal models for depression. Rats were subjected to 9 weeks of daily stress and behaviorally characterized using the sucrose consumption test into anhedonic and resilient animals based on their response to stress. Different subtypes of GABAergic interneurons were visualized by immunohistochemistry using antibodies for parvalbumin (PV), calretinin (CR), calbindin (CB), cholecystokinin (CCK), somatostatin (SOM), and neuropeptide Y (NPY). We used an unbiased quantification method to systematically count labeled cells in different subareas of the dorsal and ventral hippocampus. Chronic stress reduced the number of specific interneurons in distinct hippocampal subregions significantly. PV+ and CR+ neurons were reduced in all dorsal subareas, whereas in the ventral part only the CA1 was affected. Stress had the most pronounced effect on the NPY+ and SOM+ cells and reduced their number in almost all dorsal and ventral subareas. Stress had no effect on the CCK+ and CB+ interneurons. In most cases the effect of stress was irrespective to the behavioral phenotype. However, in a few specific areas the number of SOM+, NPY+, and CR+ neurons were significantly reduced in anhedonic animals compared to the resilient group. Overall, these data clearly demonstrate that chronic stress affects the structural integrity of specific GABAergic neuronal subpopulations and this should also affect the functioning of these hippocampal GABAergic networks.

Topics: Analysis of Variance; Animals; Calbindin 1; Cell Count; Cholecystokinin; Disease Models, Animal; Food Preferences; GABAergic Neurons; Hippocampus; Interneurons; Male; Nerve Tissue Proteins; Peptide Fragments; Rats; Rats, Wistar; Stress, Psychological; Sucrose; Sweetening Agents

Ethanol-induced neuronal loss is closely related to the pathogenesis of fetal alcohol spectrum disorders. The cerebellum is one of the brain areas that are most sensitive to ethanol. The mechanism underlying ethanol neurotoxicity remains unclear. Our previous in vitro studies have shown that the double-stranded RNA (dsRNA)-activated protein kinase (PKR) regulates neuronal apoptosis upon ethanol exposure and ethanol activates PKR through association with its intracellular activator RAX. However, the role of PKR and its interaction with RAX in vivo have not been investigated. In the current study, by utilizing N-PKR-/- mice, C57BL/6J mice with a deficient RAX-binding domain in PKR, we determined the critical role of RAX/PKR association in PKR-regulated ethanol neurotoxicity in the developing cerebellum. Our data indicate that while N-PKR-/- mice have a similar BAC profile as wild-type mice, ethanol induces less brain/body mass reduction as well as cerebellar neuronal loss. In addition, ethanol promotes interleukin-1β (IL-1β) secretion, and IL-1β is a master cytokine regulating inflammatory response. Importantly, ethanol-promoted IL-1β secretion is inhibited in the developing cerebellum of N-PKR-/- mice. Thus, RAX/PKR interaction and PKR activation regulate ethanol neurotoxicity in the developing cerebellum, which may involve ethanol-induced neuroinflammation. Further, PKR could be a possible target for pharmacological intervention to prevent or treat fetal alcohol spectrum disorder (FASD).

Topics: Age Factors; Animals; Animals, Genetically Modified; Animals, Newborn; Apoptosis; Cells, Cultured; Central Nervous System Depressants; Cerebellum; Cytokines; Disease Models, Animal; eIF-2 Kinase; Ethanol; Female; Gene Expression Regulation, Developmental; Humans; Male; Mice; Mice, Inbred C57BL; Neurons; Neurotoxicity Syndromes; Organ Size; Sincalide; Time Factors

Drosophila lethal (2) giant larvae (lgl) has been reported as a tumor suppressor and could regulate the Drosophila hippo signaling. Human giant larvae-1(Hugl-1), one human homologue of Drosophila lgl, also has been reported to be involved in the development of some human cancers. However, whether Hugl-1 is associated with the pathogenesis of malignant gliomas remains poorly understood. In the present work, we examined the effect of Hugl-1 on glioma cell growth both in vitro and in vivo. Firstly, we found that Hugl-1 protein levels decreased in the human glioma tissues, suggesting that Hugl-1 is involved in glioma progression. Unfortunately, either stably or transiently over-expressing Hugl-1 did not affect glioma cell proliferation in vitro. In addition, Hugl-1 over-expression did not regulate hippo signaling pathway. Interestingly, over-expression of Hugl-1 not only inhibited gliomagenesis but also markedly inhibited cell proliferation and promoted the apoptosis of U251 cells in an orthotopic model of nude mice. Taken together, this study provides the evidence that Hugl-1 inhibits glioma cell growth in intracranial model of nude mice, suggesting that Hugl-1 might be a potential tumor target for glioma therapy.

Topics: Animals; Astrocytoma; Brain Neoplasms; Cell Line, Tumor; Cell Proliferation; Cytoskeletal Proteins; Disease Models, Animal; Female; Gene Expression Regulation, Neoplastic; Green Fluorescent Proteins; Humans; Ki-67 Antigen; Male; Mice; Mice, Nude; Phenylurea Compounds; Sincalide; Transfection

Emerging data have demonstrated that peroxisome proliferator-activated receptor δ (PPARδ) activation confers a potentially neuroprotective role in some neurodegenerative diseases. However, whether PPARδ is involved in depression is unknown.. In this study, PPARδ was firstly investigated in the chronic mild stress (CMS) and learned helplessness (LH) models of depression. The changes in depressive behaviors and hippocampal neurogenesis were investigated after PPARδ overexpression by microinfusion of the lentiviral vector, containing the coding sequence of mouse PPARδ (LV-PPARδ), into the bilateral dentate gyri of the hippocampus or PPARδ activation by repeated systemic administration of PPARδ agonist GW0742 (5 or 10mg/kg.d, i.p., for 21 d).. We found that both CMS and LH resulted in a significant decrease in the PPARδ expression in the hippocampi of mice, and this change was reversed by treatment with the antidepressant fluoxetine. PPARδ overexpression and PPARδ activation each suppressed the CMS- and LH-induced depressive-like behavior and produced an antidepressive effect. In vivo or in vitro studies also showed that both overexpression and activation of PPARδ enhanced proliferation or differentiation of neural stem cells in the hippocampi of mice.. These results suggest that hippocampal PPARδ upregulation represses stress-induced depressive behaviors, accompanied by enhancement of neurogenesis.

Topics: Animals; Cell Differentiation; Depression; Disease Models, Animal; Gene Expression Regulation; Glial Fibrillary Acidic Protein; Hindlimb Suspension; Hippocampus; Male; Mice; Mice, Inbred ICR; Neural Stem Cells; Neurogenesis; Phosphopyruvate Hydratase; PPAR delta; Sincalide; Stress, Psychological; Thiazoles; Time Factors; Transduction, Genetic

To investigate roles of sphincter of Oddi (SO) motility played in pigment gallbladder stone formation in model of guinea pigs.. Thirty-four adult male Hartley guinea pigs were divided randomly into two groups: the control group and pigment stone group. The pigment stone group was divided into 4 subgroups with 6 guinea pigs each according to time of sacrifice, and were fed a pigment lithogenic diet and sacrificed after 3, 6, 9 and 12 wk. SO manometry and recording of myoelectric activity of the guinea pigs were obtained by multifunctional physiograph at each stage. Serum vasoactive intestinal peptide (VIP), gastrin and cholecystokinin octapeptide (CCK-8) were detected at each stage in the process of pigment gallbladder stone formation by enzyme-linked immunosorbent assay.. The incidence of pigment gallstone formation was 0%, 0%, 16.7% and 66.7% in the 3-, 6-, 9- and 12-wk group, respectively. The frequency of myoelectric activity decreased in the 3-wk group. The amplitude of myoelectric activity had a tendency to decrease but not significantly. The frequency of the SO decreased significantly in the 9-wk group. The SO basal pressure and common bile duct pressure increased in the 12-wk group (25.19 ± 7.77 mmHg vs 40.56 ± 11.81 mmHg, 22.35 ± 7.60 mmHg vs 38.51 ± 11.57 mmHg, P < 0.05). Serum VIP was significantly elevated in the 6- and 12-wk groups and serum CCK-8 was decreased significantly in the 12-wk group.. Pigment gallstone-causing diet may induce SO dysfunction. The tension of the SO increased. The disturbance in SO motility may play a role in pigment gallstone formation, and changes in serum VIP and CCK-8 may be important causes of SO dysfunction.

Topics: Animals; Cholestasis; Disease Models, Animal; Gallstones; Gastrins; Guinea Pigs; Male; Manometry; Membrane Potentials; Pressure; Sincalide; Sphincter of Oddi; Time Factors; Vasoactive Intestinal Peptide

Cholecystokinin (CCK)-induced suppression of feeding is mediated by vagal sensory neurons that are destroyed by the neurotoxin capsaicin (CAP). Here we determined whether CAP-sensitive neurons mediate anorexic responses to intravenous infusions of gut hormones peptide YY-(3-36) [PYY-(3-36)] and glucagon-like peptide-1 (GLP-1). Rats received three intraperitoneal injections of CAP or vehicle (VEH) in 24 h. After recovery, non-food-deprived rats received at dark onset a 3-h intravenous infusion of CCK-8 (5, 17 pmol·kg⁻¹·min⁻¹), PYY-(3-36) (5, 17, 50 pmol·kg⁻¹·min⁻¹), or GLP-1 (17, 50 pmol·kg⁻¹·min⁻¹). CCK-8 was much less effective in reducing food intake in CAP vs. VEH rats. CCK-8 at 5 and 17 pmol·kg⁻¹·min⁻¹ reduced food intake during the 3-h infusion period by 39 and 71% in VEH rats and 7 and 18% in CAP rats. In contrast, PYY-(3-36) and GLP-1 were similarly effective in reducing food intake in VEH and CAP rats. PYY-(3-36) at 5, 17, and 50 pmol·kg⁻¹·min⁻¹ reduced food intake during the 3-h infusion period by 15, 33, and 70% in VEH rats and 13, 30, and 33% in CAP rats. GLP-1 at 17 and 50 pmol·kg⁻¹·min⁻¹ reduced food intake during the 3-h infusion period by 48 and 60% in VEH rats and 30 and 52% in CAP rats. These results suggest that anorexic responses to PYY-(3-36) and GLP-1 are not primarily mediated by the CAP-sensitive peripheral sensory neurons (presumably vagal) that mediate CCK-8-induced anorexia.

Topics: Animals; Anorexia; Behavior, Animal; Capsaicin; Cholecystokinin; Disease Models, Animal; Energy Intake; Feeding Behavior; Glucagon-Like Peptide 1; Infusions, Intravenous; Injections, Intraperitoneal; Intestinal Mucosa; Intestine, Small; Male; Neuritis; Neurons, Afferent; Peptide Fragments; Peptide YY; Rats; Vagus Nerve; Vagus Nerve Diseases

Acupuncture or electroacupuncture (EA) potentially offers a nonpharmacological approach to reduce high blood pressure (BP). However, ~70% of the patients and animal subjects respond to EA, while 30% do not. EA acts, in part, through an opioid mechanism in the rostral ventrolateral medulla (rVLM) to inhibit sympathoexcitatory reflexes induced by gastric distention. CCK-8 opposes the action of opioids during analgesia. Therefore, we hypothesized that CCK-8 in the rVLM antagonizes EA modulation of sympathoexcitatory cardiovascular reflex responses. Male rats anesthetized with ketamine and α-chloralose subjected to repeated gastric distension every 10 min were examined for their responsiveness to EA (2 Hz, 0.5 ms, 1-4 mA) at P5-P6 acupoints overlying median nerve. Repeated gastric distension every 10 min evoked consistent sympathoexcitatory responses. EA at P5-P6 modulated gastric distension-induced responses. Microinjection of CCK-8 in the rVLM reversed the EA effect in seven responders. The CCK1 receptor antagonist devazepide microinjected into the rVLM converted six nonresponders to responders by lowering the reflex response from 21 ± 2.2 to 10 ± 2.9 mmHg (first vs. second application of EA). The EA modulatory action in rats converted to responders with devazepide was reversed with rVLM microinjection of naloxone (n = 6). Microinjection of devazepide in the absence of a second application of EA did not influence the primary pressor reflexes of nonresponders. These data suggest that CCK-8 antagonizes EA modulation of sympathoexcitatory cardiovascular responses through an opioid mechanism and that inhibition of CCK-8 can convert animals that initially are unresponsive to EA to become responsive.

Topics: Animals; Blood Pressure; Devazepide; Disease Models, Animal; Electroacupuncture; Enkephalins; Hormone Antagonists; Hypertension; Male; Mechanotransduction, Cellular; Medulla Oblongata; Microinjections; Narcotic Antagonists; Pressure; Rats; Rats, Sprague-Dawley; Receptor, Cholecystokinin A; Reflex; Sincalide; Stomach; Time Factors

To observe changes of cholecystokinin octapeptide (CCK-8), calcitonin gene related peptide (CGRP), substance P (SP), and vasoactive intestinal peptide (VIP) in each tissue of the digestive system of allergic asthma (AA) model rats.. The pulmonary disease (AA) rat model was duplicated by 1% ovalbumin. Its effect on the pathological morphology of the six main parts of the digestive system (stomach, duodenum, jejunum, ileum, colon and rectum) and related regulating factors such as CCK8, CGRP, SP, and VIP were observed.. The pathological morphology of the lung was synchronously changed as that of the colon of model rats. But there was no obvious change in the stomach, duodenum, jejunum, ileum, or rectum. Significant changes occurred in CCK8 (79 961.4 +/- 12 577.9, 48 519.5 +/- 12 240.7), CGRP (41 950.1 +/- 12 600.1, 38 059.8 +/- 11 942.4), and SP (88 243.9 +/- 32 177.2, 47 417.8 +/- 16 462.4), and VIP (20 711.4 +/- 7 334.6, 43 208.1 +/- 13 433.8) of the lung tissue and the colon tissue of model rats (P < 0. 05, P < 0.01). But there was no significant change in the aforesaid substances of the stomach, duodenum, jejunum, ileum and rectum (P > 0.05).. Pulmonary disease might affect the colon, inducing pathological changes of the colon tissue and changes of related regulating factors such as CCK8, CGRP, SP, and VIP. It showed no significant effect on the stomach, duodenum, jejunum, ileum and rectum.

Topics: Animals; Asthma; Calcitonin Gene-Related Peptide; Colon; Disease Models, Animal; Lung; Male; Rats; Rats, Wistar; Sincalide; Substance P; Vasoactive Intestinal Peptide

Cholecystokinin (CCK) is a rapidly degraded gastrointestinal peptide that stimulates satiety and insulin secretion. We aimed to investigate the beneficial weight-lowering and metabolic effects of the novel N-terminally modified CCK analogue, (pGlu-Gln)-CCK-8.. The biological actions of (pGlu-Gln)-CCK-8 were comprehensively evaluated in pancreatic clonal BRIN BD11 cells and in vivo in high-fat-fed and ob/ob mice.. (pGlu-Gln)-CCK-8 was completely resistant to enzymatic degradation and its satiating effects were significantly (p < 0.05 to p < 0.001) more potent than CCK-8. In BRIN-BD11 cells, (pGlu-Gln)-CCK-8 exhibited enhanced (p < 0.01 to p < 0.001) insulinotropic actions compared with CCK-8. When administered acutely to high-fat-fed or ob/ob mice, (pGlu-Gln)-CCK-8 improved glucose homeostasis. Sub-chronic twice daily injections of (pGlu-Gln)-CCK-8 in high-fat-fed mice for 28 days significantly decreased body weight (p < 0.05 to p < 0.001), accumulated food intake (p < 0.05 to p < 0.001), non-fasting glucose (p < 0.05) and triacylglycerol deposition in pancreatic (p < 0.01), adipose (p < 0.05) and liver (p < 0.001) tissue, and improved oral (p < 0.05) and i.p. (p < 0.05) glucose tolerance and insulin sensitivity (p < 0.001). Similar observations were noted in ob/ob mice given twice daily injections of (pGlu-Gln)-CCK-8. In addition, these beneficial effects were not reproduced by simple dietary restriction and were not associated with changes in energy expenditure. There was no evidence for development of tolerance to (pGlu-Gln)-CCK-8, and analysis of histology or blood-borne markers for pancreatic, liver and renal function in mice treated with (pGlu-Gln)-CCK-8 suggested little abnormal pathology.. These studies emphasise the potential of (pGlu-Gln)-CCK-8 for the alleviation of obesity and insulin resistance.

Topics: Animals; Cholecystokinin; Comorbidity; Diabetes Mellitus; Disease Models, Animal; Glucose; Homeostasis; Insulin Resistance; Male; Mice; Mice, Obese; Obesity; Sincalide

The purpose of this study was to evaluate the potential therapeutic effect of cholecystokinin octapeptide (CCK-8) on collagen-induced arthritis (CIA), an accepted murine experimental disease model with diverse histopathological features similar to human rheumatoid arthritis (RA). CIA was induced in DBA/1J mice by immunization with chicken collagen type II (CII). CCK-8 at different doses was intraperitoneally administered daily for 1 week. Mice treated with CCK-8 at doses of 5 and 10 nmol but not 1 nmol displayed much delayed onset of CIA and significantly lower incidence and decreased severity of arthritis. CCK-8 treatment significantly reduced the production of cytokines (IL-17, IL-23, IL-6 and TNF-α) and chemokines monocyte chemoattractant protein 1 in the joints of arthritic mice or in synovial cell culture supernatant, and increased the levels of IFN-γ and TGF-β. T cells from CCK-8 treated mice proliferated much less, produced low level of IL-17 and high levels of IFN-γ and TGF-β. Moreover, CCK-8 treated mice showed lower levels of CII-specific IgG, particularly that of IgG2a, in sera than those from control mice. These results indicate that CCK-8 is effective in suppressing both inflammatory and Th17 responses in CIA. CCK-8 may represent a new therapeutic modality for rheumatoid arthritis.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Arthritis, Experimental; Cells, Cultured; Disease Models, Animal; Female; Immunosuppressive Agents; Incidence; Inflammation Mediators; Mice; Mice, Inbred DBA; Severity of Illness Index; Sincalide; Synovial Membrane; Th17 Cells

Acute pancreatitis is an inflammatory disease of the pancreas caused by release of activated digestive enzymes in the pancreas. A number of therapeutic options have been explored for acute pancreatitis, but none has been unambiguously proven to be effective. Rosiglitazone has been shown to be efficacious in acute pancreatitis; thus, the present study was planned to evaluate the effect of rosiglitazone on pancreatic regeneration. Pancreatitis was induced by l-arginine in rats which were divided into three groups: cholecystokinin (CCK-8), rosiglitazone and vehicle. Rats were sacrificed at four time points after induction of pancreatitis i.e. 24h, day 3, day 14 and day 28 for determination of biochemical parameters and histological examination. Rate of DNA synthesis, immunohistochemistry and RT-PCR were performed at day 3 and day 7. Drug administration was started 2h after last L-arginine injection and continued till the day of sacrifice. The lower levels of enzyme in rosiglitazone-treated group compared to vehicle group proved the efficacy of rosiglitazone treatment in reducing severity of acute pancreatitis. The nucleic acid content and rate of DNA synthesis were significantly higher in rosiglitazone group indicating promotion of pancreatic regeneration. The histopathological score were lower in rosiglitazone group. Rosiglitazone treatment promoted pancreatic regeneration after acute injury. Currently, only symptomatic treatment is available, regeneration of pancreatic tissue can be a future strategy in the management of acute pancreatitis. Further studies are required to support the findings of the present study.

Topics: Acute Disease; Animals; Arginine; Disease Models, Animal; DNA; Female; Male; Pancreatitis; PPAR gamma; Rats; Rats, Wistar; Regeneration; Reverse Transcriptase Polymerase Chain Reaction; Rosiglitazone; Severity of Illness Index; Sincalide; Thiazolidinediones; Time Factors

To investigate the effects of cholecystokinin octapeptide on thermoregulation, postresuscitation myocardial function, neurologic outcome, and duration of survival in a rat model of cardiopulmonary resuscitation.. : Prospective, randomized, placebo-controlled experimental study.. University-affiliated animal research laboratory.. Ten male Sprague-Dawley rats.. Ventricular fibrillation was induced and untreated for 6 mins. Defibrillation was attempted after 8 mins of cardiopulmonary resuscitation. Animal temperature was adjusted to 37.0 °C with the aid of a heating lamp. At 30 mins after resuscitation, animals were randomized to receive an intravenous injection of either cholecystokinin octapeptide (200 μg/kg in 0.3 mL saline) or vehicle placebo (0.3 mL saline). The ambient temperature settings and that of the distance of the heating lamp from the animal remained the same in both groups throughout the entire experiment.. Body temperature, hemodynamic measurements, and postresuscitation myocardial function, including cardiac output, left ventricular ejection fraction, and myocardial performance index, were measured together with neurologic deficit scores and duration of survival.. After injection of cholecystokinin octapeptide, blood temperature decreased progressively from 37.0 °C to 34.8 °C 5 hrs after resuscitation and returned to 37.0 °C at 9 hrs after injection. In the control group, blood temperature was sustained at 37.0 °C ± 0.2 °C during the same period of observation. Myocardial and neurologic function and duration of survival were significantly better in the cholecystokinin octapeptide-treated animals when compared to the control group.. : In a rat model of cardiopulmonary resuscitation, cholecystokinin octapeptide induced mild hypothermia, attenuated postresuscitation myocardial dysfunction, and improved neurologic outcome and duration of survival.

Topics: Animals; Body Temperature; Cardiopulmonary Resuscitation; Disease Models, Animal; Hemodynamics; Hypothermia, Induced; Male; Rats; Rats, Sprague-Dawley; Sincalide

Cholecystokinin octapeptide (CCK-8) is a neuropeptide, and is shown to be a potent immunomodulator with predominant anti-inflammatory effects. Although the regulatory effect of CCK-8 on macrophages and B cells has been defined, the effect of CCK-8 on dendritic cells (DCs) and T cells is not well understood. In this study, we showed that CCK-8 reduced the expression of CD80, CD86, and MHCII on DCs. Moreover, CCK-8 promoted Th1 and inhibited Th17 polarization by increasing the production of IL-12 and decreasing the production of IL-6 and IL-23 on DCs in vitro and in vivo. In addition, intraperitoneal administration of CCK-8 to mice with collagen-induced arthritis (CIA) was found to effectively reduce the incidence of arthritis, delay its onset and prevent the occurrence of joint damage. Collectively, these results suggest that CCK-8 significantly suppresses the incidence and severity of CIA in mice, through the inhibition of DC mediated Th17 polarization.

Topics: Animals; Antigens, CD; Arthritis, Experimental; Cell Differentiation; Collagen Type II; Dendritic Cells; Disease Models, Animal; Female; Flow Cytometry; Injections, Intraperitoneal; Interleukin-12; Interleukin-23; Interleukin-6; Joints; Mice; Mice, Inbred DBA; Polymerase Chain Reaction; Signal Transduction; Sincalide; Th1 Cells; Th17 Cells

Z-360 is an orally active cholecystokinin-2 (CCK2)/gastrin receptor antagonist currently under development as a therapeutic drug for pancreatic cancer. It was previously reported that Z-360 treatment in combination with gemcitabine prolonged the survival period in a lethal pancreatic cancer xenograft model in mice. In a phase Ib/IIa clinical study, Z-360 treatment displayed a trend of reduced pain in patients with advanced pancreatic cancer in combination with gemcitabine including analgesics such as opioids. Here, we investigated the mechanism of analgesic action of Z-360 in a severe cancer-induced pain model in mice, which is considered to be opioid-resistant, by examining ephrin B1 gene expression, N-methyl-D-aspartate receptor NR2B subunit phosphorylation, and interleukin-1β (IL-1β) production.. In a mouse model of cancer-induced pain, ephrin B1 gene expression in dorsal root ganglia (DRGs) and the phosphorylation of NR2B in the spinal cord were induced. Z-360 treatment inhibited both ephrin B1 gene expression and the phosphorylation of NR2B. In addition, IL-1β production increased in the cancer-inoculated hind paw of mice, but could be suppressed by treatment with Z-360. Moreover, we observed that the CCK1 receptor antagonist devazepide similarly suppressed up-regulation of ephrin B1 gene expression and IL-1β production, and that the intraperitoneal injection of sulfated CCK-8 induced the production of IL-1β in the cancer-inoculated region.. We have identified a novel pain cascade, in which IL-1β production in cancer-inoculated regions induces ephrin B1 gene expression in DRGs and then ephrin B1 enhances the tyrosine phosphorylation of NR2B via Eph B receptor in the spinal cord. Notably, Z-360 relieves cancer-induced pain by preventing this pain cascade through the suppression of IL-1β production, likely via the blockade of CCK1 receptor. The pre-clinical results presented here support the analgesic action of Z-360 in pancreatic cancer patients with severe, opioid-resistant pain. Pre-clinical and clinical results have demonstrated that Z-360 combined with gemcitabine represents a promising pancreatic cancer therapy approach with characteristic analgesic effects in addition to the prolongation of survival.

Topics: Animals; Benzodiazepinones; Cell Line, Tumor; Devazepide; Disease Models, Animal; Ephrin-B1; Extremities; Ganglia, Spinal; Gene Expression Regulation, Neoplastic; Injections; Interleukin-1beta; Mice; Pain; Pancreatic Neoplasms; Phosphorylation; Receptors, Eph Family; Receptors, N-Methyl-D-Aspartate; Sincalide; Up-Regulation

Animal models of inflammatory pain are characterized by the release of inflammatory mediators such as cytokines and neurotrophic factors, and enhanced analgesic sensitivity to opioids. In this study, we examine the mechanisms underlying this effect, in particular the roles of cholecystokinin (CCK) and nerve growth factor (NGF), in an animal model of central nervous system (CNS) inflammation induced by spinal administration of lipopolysaccharide (LPS). Although spinal administration of LY-225910 (25 ng), a CCK-B antagonist, enhanced morphine analgesia in naïve rats, it was unable to do so in LPS-treated animals. Conversely, spinal CCK-8S administration (1 ng) decreased morphine analgesia in LPS-treated rats, but not in naïve animals. Further, spinal anti-NGF (3 microg) was able to reduce morphine analgesia in LPS-treated rats, but not in naïve animals, an effect that was reversed by spinal administration of LY-225910. While CCK-8S concentration was increased in spinal cord extracts of LPS animals as compared to controls, morphine-induced spinal CCK release in the extracellular space, as measured by in-vivo spinal cord microdialysis was inhibited in LPS animals as compared to controls, and this was reversed by anti-NGF pretreatment. Finally, chronic spinal administration of beta-NGF (7 microg/day) for 7 days enhanced spinal morphine analgesia, possibly by mimicking a CNS inflammatory state. We suggest that in intrathecally LPS-treated rats, spinal CCK release is altered resulting in enhanced morphine analgesia, and that this mechanism may be regulated to an important extent by NGF.

Topics: Analgesics; Animals; Central Nervous System Diseases; Cholecystokinin; Disease Models, Animal; Inflammation; Injections, Spinal; Lipopolysaccharides; Male; Morphine; Nerve Growth Factor; Rats; Rats, Long-Evans; Sincalide; Spinal Cord

We evaluated the possible additive effect induced by the administration of the anticonvulsant vigabatrin (VGB) and cholecystokinin-8 sulfate (CCK-8S) on an experimental model of partial complex seizures (maximal dentate gyrus activation, MDA). Moreover, the functional involvement of gamma-aminobutyric acid (GABA) neurotransmission was tested by iontophoretically administering bicuculline (GABA receptor antagonist) in the dentate gyrus.. Urethane anesthetized rats were pretreated with VGB (50, 100 or 200 mg/kg, i.p.) or CCK-8S (8 nmol/kg, i.p.) alone or coadministered with VGB (50 mg/kg, i.p.). Dentate gyrus epileptic activity was obtained through the repetitive electrical stimulation of the angular bundle. MDA latency, duration, and poststimulus afterdischarge (AD) duration were evaluated. The extracellular activity of some dentate neurons was recorded before and during bicuculline iontophoresis.. Only the higher dose of VGB reduced the mean duration of dentate MDA and AD. CCK-8S significantly decreased the number of animals exhibiting MDA responses, characterized by increased latency and shorter duration. The coadministration of CCK-8S and VGB (50 mg/kg) significantly increased the anticonvulsant effects, either reducing the number of responding animals or decreasing both MDA and AD durations. During bicuculline iontophoresis, all the modifications induced on the MDA-related activity of dentate neurons by the pretreatments (VGB and/or CCK-8S) were abolished.. The results indicate that CCK-8S significantly enhances the VGB-induced anticonvulsant effect in the MDA model of partial epilepsy, probably through an increase of GABA cerebral levels. Such increased anticonvulsant effect becomes evident by using VGB at a lower dose.

Topics: Analysis of Variance; Animals; Anticonvulsants; Bicuculline; Convulsants; Dentate Gyrus; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Administration Schedule; Drug Synergism; Drug Therapy, Combination; Electric Stimulation; Epilepsy, Complex Partial; Evoked Potentials; Male; Nootropic Agents; Rats; Rats, Wistar; Reaction Time; Sincalide; Vigabatrin

Acinar cells in pancreatitis die through apoptosis and necrosis, the roles of which are different. The severity of experimental pancreatitis correlates directly with the extent of necrosis and inversely, with apoptosis. Apoptosis is mediated by the release of cytochrome c into the cytosol followed by caspase activation, whereas necrosis is associated with the mitochondrial membrane potential (DeltaPsim) loss leading to ATP depletion. Here, we investigate the role of Bcl-2 proteins in apoptosis and necrosis in pancreatitis. We found up-regulation of prosurvival Bcl-2 proteins in pancreas in various experimental models of acute pancreatitis, most pronounced for Bcl-xL. This up-regulation translated into increased levels of Bcl-xL and Bcl-2 in pancreatic mitochondria. Bcl-xL/Bcl-2 inhibitors induced DeltaPsim loss and cytochrome c release in isolated mitochondria. Corroborating the results on mitochondria, Bcl-xL/Bcl-2 inhibitors induced DeltaPsim loss, ATP depletion and necrosis in pancreatic acinar cells, both untreated and hyperstimulated with CCK-8 (in vitro pancreatitis model). Together Bcl-xL/Bcl-2 inhibitors and CCK induced more necrosis than either treatment alone. Bcl-xL/Bcl-2 inhibitors also stimulated cytochrome c release in acinar cells leading to caspase-3 activation and apoptosis. However, different from their effect on pronecrotic signals, the stimulation by Bcl-xL/Bcl-2 inhibitors of apoptotic responses was less in CCK-treated than control cells. Therefore, Bcl-xL/Bcl-2 inhibitors potentiated CCK-induced necrosis but not apoptosis. Correspondingly, transfection with Bcl-xL siRNA stimulated necrosis but not apoptosis in the in vitro pancreatitis model. Further, in animal models of pancreatitis Bcl-xL up-regulation inversely correlated with necrosis, but not apoptosis. Results indicate that Bcl-xL and Bcl-2 protect acinar cells from necrosis in pancreatitis by stabilizing mitochondria against death signals. We conclude that Bcl-xL/Bcl-2 inhibition would aggravate acute pancreatitis, whereas Bcl-xL/Bcl-2 up-regulation presents a strategy to prevent or attenuate necrosis in pancreatitis.

Topics: Adenosine Triphosphate; Animals; Base Sequence; bcl-X Protein; Capsid Proteins; Caspase 3; Ceruletide; Cytochromes c; Disease Models, Animal; DNA Primers; Gene Expression; In Vitro Techniques; Male; Membrane Potential, Mitochondrial; Mice; Mitochondria; Necrosis; Pancreas; Pancreatitis, Acute Necrotizing; Proto-Oncogene Proteins c-bcl-2; Rats; Rats, Sprague-Dawley; RNA, Messenger; Sincalide

Receptor-stimulated Ca(2+) influx is a critical component of the Ca(2+) signal and mediates all cellular functions regulated by Ca(2+). However, excessive Ca(2+) influx is highly toxic, resulting in cell death, which is the nodal point in all forms of pancreatitis. Ca(2+) influx is mediated by store-operated channels (SOCs). The identity and function of the native SOCs in most cells is unknown.. Here, we determined the role of deletion of Trpc3 in mice on Ca(2+) signaling, exocytosis, intracellular trypsin activation, and pancreatitis.. Deletion of TRPC3 reduced the receptor-stimulated and SOC-mediated Ca(2+) influx by about 50%, indicating that TRPC3 functions as an SOC in vivo. The reduced Ca(2+) influx in TRPC3(-/-) acini resulted in reduced frequency of the physiologic Ca(2+) oscillations and of the pathologic sustained increase in cytosolic Ca(2+) levels caused by supramaximal stimulation and by the toxins bile acids and palmitoleic acid ethyl ester. Consequently, deletion of TRPC3 shifted the dose response for receptor-stimulated exocytosis and prevented the pathologic inhibition of digestive enzyme secretion at supramaximal agonist concentrations. Accordingly, deletion of TRPC3 markedly reduced intracellular trypsin activation and excessive actin depolymerization in vitro and the severity of pancreatitis in vivo.. These findings establish the native TRPC3 as an SOC in vivo and a role for TRPC3-mediated Ca(2+) influx in the pathogenesis of acute pancreatitis and suggest that TRPC3 should be considered a target for prevention of pancreatic damage in acute pancreatitis.

Topics: Actins; Acute Disease; Animals; Calcium Signaling; Carbachol; Ceruletide; Cholinergic Agonists; Disease Models, Animal; Dose-Response Relationship, Drug; eIF-2 Kinase; Enzyme Activation; Enzyme Inhibitors; Exocytosis; Indoles; Membrane Potentials; Mice; Mice, Knockout; Pancreas; Pancreatitis; Phosphorylation; Sarcoplasmic Reticulum; Sarcoplasmic Reticulum Calcium-Transporting ATPases; Severity of Illness Index; Sincalide; Taurocholic Acid; TRPC Cation Channels; Trypsin

cis-4-(Piperazin-1-yl)-5,6,7a,8,9,10,11,11a-octahydrobenzofuro[2,3-h]quinazolin-2-amine, 4 (A-987306) is a new histamine H(4) antagonist. The compound is potent in H(4) receptor binding assays (rat H(4), K(i) = 3.4 nM, human H(4) K(i) = 5.8 nM) and demonstrated potent functional antagonism in vitro at human, rat, and mouse H(4) receptors in cell-based FLIPR assays. Compound 4 also demonstrated H(4) antagonism in vivo in mice, blocking H(4)-agonist induced scratch responses, and showed anti-inflammatory activity in mice in a peritonitis model. Most interesting was the high potency and efficacy of this compound in blocking pain responses, where it showed an ED(50) of 42 mumol/kg (ip) in a rat post-carrageenan thermal hyperalgesia model of inflammatory pain.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzofurans; Carrageenan; Disease Models, Animal; Drug Design; Drug Evaluation, Preclinical; Humans; Hyperalgesia; Ligands; Mice; Molecular Structure; Pain; Peritonitis; Quinazolines; Rats; Receptors, G-Protein-Coupled; Receptors, Histamine; Receptors, Histamine H4; Stereoisomerism; Structure-Activity Relationship

Cholecystokinin (CCK) stimulates the release of amylase and lipase from the normal pancreas. However, it is not clear to what extent this occurs in the early stages of pancreatitis induced by biliary tract obstruction in the rat and whether CCK initiates an inflammatory cascade in this condition.. Selective CCK1 receptor antagonists, JNJ-17156516 ((S)-(3-[5-(3,4-dichloro-phenyl)-1-(4-methoxy-phenyl)-1H-pyrazol-3-yl]-2-m-tolyl-propionic acid) and dexloxiglumide, were used to assess the response of plasma amylase and lipase to a CCK analogue, CCK8S, in normal rats and in rats with bile duct ligation.. Both antagonists suppressed CCK8S-induced elevation of plasma amylase activity in normal rats. JNJ-17156516 was more potent than dexloxiglumide (ED(50)=8.2 vs >30 micromol kg(-1) p.o.) and produced a longer lived inhibition (6 vs 2 h). Plasma amylase and lipase activity were elevated in parallel to CCK plasma concentrations after bile duct ligation and both activities were suppressed in a dose-dependent manner by JNJ-17156516 and dexloxiglumide. JNJ-17156516 was approximately 5- to 10-fold more potent than dexloxiglumide. Infusion of CCK8S to naïve rats to achieve levels similar to those observed after bile duct ligation (20 pM) increased plasma amylase activity and activated nuclear factor-kappaB in the pancreas. These effects were prevented by pretreatment with JNJ-17156516.. The elevation of plasma amylase and lipase activity in the early stages of obstruction-induced pancreatitis is largely driven by elevation of plasma CCK concentration and activation of CCK1 receptors. These data show that CCK is an initiating factor in acute pancreatitis in the rat.

Topics: Acute Disease; Amylases; Animals; Bile Ducts; Cholecystokinin; Disease Models, Animal; Ligation; Lipase; Male; NF-kappa B; Pancreatitis; Pentanoic Acids; Phenylpropionates; Pyrazoles; Rats; Rats, Sprague-Dawley; Receptor, Cholecystokinin A; Sincalide

The mechanisms that trigger gallbladder evacuation dysfunction, the key risk factor for gallstone formation, have not yet been fully elucidated. The sphincter of Oddi (SO) plays important roles in the regulation of gallbladder evacuation and maintenance of normal hydraulic pressure of the biliary tract. The aim of our study was to investigate the effects of hypercholesterolemia on the motility function of SO and the underlying mechanisms of SO dysfunction (SOD).. Forty New Zealand white rabbits were divided randomly into the control group fed with standard chow and the experimental (Ch) group fed with a high-cholesterol diet for 8 weeks. Changes in the maximal gallbladder emptying rate, gallbladder evacuation with cholecystokinin-octapeptide (CCK-8) stimulation and SO functions of both groups were measured in vivo; B ultrasound examination was used for dynamic observation of peristaltic movements in vivo; SO pressure was measured using manometry; morphological characteristics were observed by electronic microscope; laser scanning confocal fluorescence microscopy was used to identify changes in [Ca]i and Ca oscillation in primary SO smooth muscle cells (SMCs).. Gallbladder cholestasis was observed during early stages of gallstone formation in Ch rabbits. CCK-8 could not improve the gallbladder cholestatic state in Ch group. Passive dilation of SO significantly improved the cholestatic state in Ch rabbits (P<0.05), although the maximal gallbladder emptying rate was still lower than that of the control group. Manometry data indicted a significant increase in the base pressure of the SO low-pressure ampulla segment and high-pressure segment (P<0.05) in Ch group. laser scanning confocal fluorescence microscopy assay data indicated that [Ca]i in SO cells of Ch group significantly increased and were in a state of overload (P<0.05); Ca oscillation signals in SO cells of Ch group were also abnormal.. Hypercholesterolemia initially induced SOD, leading to increased gallbladder evacuation resistance and cholestasis. We suggested that [Ca]i overload and/or Ca oscillation abnormality potentially play important roles in the pathogenesis of SOD.

Topics: Animals; Bile; Calcium Signaling; Cholecystography; Cholestasis; Cholesterol; Cholesterol, Dietary; Disease Models, Animal; Female; Gallbladder Emptying; Hypercholesterolemia; Male; Microscopy, Confocal; Peristalsis; Rabbits; Sincalide; Sphincter of Oddi; Sphincter of Oddi Dysfunction

Bee venom (BV) has frequently been used as a remedy for inflammatory diseases. The aim of this study was to investigate the effect of BV on cholecystokinin octapeptide (CCK-8)-induced acute pancreatitis (AP) in rats.. The BV pretreatment group: 0.25 mg/kg BV was administered subcutaneously, followed by 75 mug/kg CCK-8 subcutaneously 3 times after 1, 3, and 5 hours. This whole procedure was repeated for 5 days.. CCK-8 subcutaneously 3 times after 1, 3, and 5 hours for 5 days. The BV posttreatment group: CCK-8 subcutaneously 3 times at an interval of 2 hours for 3 days, and then 0.25 mg/kg of BV was administered subcutaneously.. CCK-8 subcutaneously 3 times at an interval of 2 hours for 3 days.. The BV pretreatment and posttreatment ameliorated many of the examined laboratory parameters (the pancreatic weight [PW]/body weight [BW] ratio, the serum amylase and lipase activity) and reduced histological damages in pancreas. Furthermore, BV pretreatment reduced the production of tumor necrosis factor-alpha, interleukin 1, and interleukin 6 and also decreased pancreatic nuclearfactor-kappaB binding activity compared with saline-treated group in the AP model. The BV also increased heat shock protein 60 (HSP60) and heat shock protein 72 (HSP72) compared with the saline-treated group in the AP model.. These findings suggest that the anti-inflammatory effect of BV in CCK-8-induced AP seems to be mediated by inhibiting nuclear factor-kappaB binding activity, and that BV may have a protective effect against AP.

Topics: Acute Disease; Amylases; Animals; Anti-Inflammatory Agents; Bee Venoms; Body Weight; Chaperonin 60; Disease Models, Animal; HSP72 Heat-Shock Proteins; Injections, Subcutaneous; Interleukin-1; Interleukin-6; Lipase; Male; NF-kappa B; Organ Size; Pancreas; Pancreatitis; Rats; Rats, Wistar; Severity of Illness Index; Sincalide; Tumor Necrosis Factor-alpha

To investigate the effect of selective Cycloo-xygenase-2 (COX-2) inhibitor 4-[5-(4-Chloro-phenyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl] benzenesulfonamide (SC-236), on the cholecystokinin (CCK)-octapeptide-induced acute pancreatitis (AP) in rats.. Wistar rat weighing 240 g to 260 g were divided into three groups. (1) Normal DMSO treated group, (2) SC-236 at 4 mg/kg treated group; SC-236 systemically administered via the intravenous (i.v.) catheter, followed by 75 microg/kg CCK octapeptide subcutaneously three times, after 1, 3 and 5 h. This whole procedure was repeated for 5 d. (3) Dimethyl sulfoxide (DMSO) treated group: an identical protocol was used in this group as in the SC-236 cohort (see 2. above). Repeated CCK octapeptide treatment resulted in a typical experimentally induced pancreatitis in the Wistar rats.. SC-236 improved the severity of CCK-octapeptide-induced AP as measured by laboratory criteria [the pancreatic weight/body weight (p.w/b.w) ratio, the level of serum amylase and lipase]. The SC-236 treated group showed minimal histologic evidence of pancreatitis and a significant reduction in myeloperoxidase activity. SC-236 also increased heat shock protein (HSP)-60 and HSP72 compared with the DMSO-treated group in the CCK-octapeptide-induced AP and also reduced the pancreatic levels of COX-2. Furthermore, SC-236 reduced proinflammatory cytokine synthesis and inhibited NF-kappaB activation compared with the DMSO-treated group in the CCK-octapeptide-induced AP.. Our results suggested that COX-2 plays pivotal role in the development of AP and COX-2 inhibitors may play a beneficial role in preventing AP.

Topics: Acute Disease; Animals; Chaperonin 60; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Disease Models, Animal; Gene Expression Regulation; HSP72 Heat-Shock Proteins; Interleukin-1; Interleukin-6; Male; NF-kappa B; Pancreas; Pancreatitis; Pyrazoles; Rats; Rats, Wistar; Sincalide; Sulfonamides; Tumor Necrosis Factor-alpha

Previous studies have identified a counterinflammatory vagal reflex in the context of endotoxic shock. We have extended this observation to show that the vagus confers protection against acute (5 days) colitis induced by dextran sodium sulfate (DSS) or by dinitrobenzene sulfonic acid (DNBS). We have shown that this is mediated via macrophages and involves the suppression of proinflammatory cytokines. In this study, we have examined whether the vagal integrity confers long-lasting protection by studying DNBS- and DSS-induced inflammatory responses in the colon at 9 to 61 days postvagotomy. The integrity of vagotomy was confirmed at all time points using CCK-induced satiety. As previously described in a DNBS and DSS model, vagotomy associated with the pyloroplasty increased all indices of inflammation. Vagotomy increased the disease activity index as well as the macroscopic and histological scores by 75 and 41%, respectively. In addition, myeloperoxidase (MPO) activity, serum levels of C-reactive protein (CRP), and colonic tissue levels of proinflammatory cytokine increased when colitis was induced 9 days postvagotomy. However, these increases in inflammatory indices were substantially diminished in mice with colitis induced 21, 33, and 61 days postvagotomy. This was accompanied by an increased production of interleukin-10, transforming growth factor-beta, Forkhead Box P3 (FOXP3) staining in colonic tissue, and serum corticosterone. These findings indicate that although vagal integrity is an important protective factor, other counterinflammatory mechanisms come into play if vagal integrity is compromised beyond 2 wk.

Topics: Animals; C-Reactive Protein; Colitis; Colon; Corticosterone; Dextran Sulfate; Dinitrofluorobenzene; Disease Models, Animal; Eating; Forkhead Transcription Factors; Interleukins; Male; Mice; Mice, Inbred C57BL; Peroxidase; Reflex; Severity of Illness Index; Sincalide; T-Lymphocytes, Regulatory; Time Factors; Transforming Growth Factor beta; Vagotomy, Truncal; Vagus Nerve

The vagus nerve inhibits the response to systemic administration of endotoxin, and we have recently extended this observation to show that the vagus attenuates acute experimental colitis in mice. The purpose of the present study was to determine whether there is a tonic counterinflammatory influence of the vagus on colitis maintained over several weeks. We assessed disease activity index, macroscopic and histological damage, myeloperoxidase (MPO) activity, and Th1 and Th2 cytokine profiles in chronic colitis induced by administration of dextran sodium sulfate (DSS) in drinking water for three cycles during 5 days with 11 days of rest between each cycle (DSS 3, 2, 2%) in healthy and vagotomized C57BL/6 mice and in mice deficient in macrophage-colony stimulating factor (M-CSF). A pyloroplasty was performed in vagotomized mice. Vagotomy accelerated the onset and the severity of inflammation during the first and second but not the third cycle. Although macroscopic scores were not significantly changed, histological scores as well as MPO activity and colonic tissue levels of IL-1alpha, TNF-alpha, IFN-gamma, and IL-18 but not IL-4 were significantly increased in vagotomized mice compared with sham-operated mice that received DSS. In control mice (without colitis), vagotomy per se did not affect any inflammatory marker. Vagotomy had no effect on the colitis in M-CSF-derived macrophage-deficient mice. These results indicate that the vagus protects against acute relapses on a background of chronic inflammation. Identification of the molecular mechanisms underlying the protective role of parasympathetic nerves opens a new therapeutic avenue for the treatment of acute relapses of chronic inflammatory bowel disease.

Topics: Animals; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Interferon-gamma; Interleukin-18; Interleukin-1beta; Interleukin-4; Macrophage Colony-Stimulating Factor; Male; Mice; Mice, Inbred C57BL; Sincalide; Tumor Necrosis Factor-alpha; Vagotomy; Vagus Nerve

To study the effects and the mechanisms of cholecystokinin octapeptide(CCK-8) on hippocampal injury during endotoxic shock (ES).. Rabbits were injected intravenously with lipopolysaccharide (LPS, 8 mg/kg) to establish ES model. Thirty-two Rabbits were divided into 4 groups at random (n = 8): control (saline, iv), LPS, CCK-8 + LPS (CCK-8 pre-administrated 30 min before LPS, iv), proglumide (Pro, nonspecific antagonist of CCK receptors) + LPS (Pro pre-administrated 30 min before LPS, iv) group. The changes of mean arterial pressure (MAP) were measured. The morphologic changes in the hippocampus were observed through light microscope (LM) and transmission electron microscope (TEM). The alterations of activities of nitric oxide synthase (NOS) and superoxide dismutase (SOD), contents of nitric oxide (NO) and malondialdehyde (MDA) in the hippocampus were assayed. Twelve Sprague-Dawley rats, grouped as that of the rabbits, were used to detect the expression of inducible NOS (iNOS) and neuronal NOS (nNOS) protein by immunohistochemistry staining.. LPS administration resulted insignificant reduction in MAP (P < 0.01 vs control group) and hydropic degeneration of neurons in the hippocampus. Compared with those of control group, the NOS activity, NO level and MDA content were increased significantly (P < 0.05, P < 0.01 and P < 0.05), while SOD activity was reduced (P < 0.01) in the hippocampus of ES rabbits. LPS administration induced the expression of iNOS protein in the cytoplasm of hippocampus neurons, and lead to stronger positive signals of nNOS than that of control group. CCK-8 pre-administration could alleviate the changes induced by LPS, while Pro pre-administration aggravated those alterations.. CCK-8 could protect hippocampus neurons against the injury induced by LPS during ES, which might be associated with its effects of suppressing the over production of NO and free radicals.

Topics: Animals; Disease Models, Animal; Hippocampus; Male; Nitric Oxide; Rabbits; Rats; Rats, Sprague-Dawley; Shock, Septic; Signal Transduction; Sincalide

Valsartan is a highly selective angiotensin II AT1-receptor antagonist for the treatment of hypertension. Valsartan is mainly excreted into the bile in unchanged form. Because valsartan has an anionic carboxyl group, we hypothesized that a series of organic anion transporters could be involved in its hepatic clearance. In this study, to identify transporters that mediate the hepatic uptake and biliary excretion of valsartan and estimate the contribution of each transporter to the overall hepatic uptake and efflux, we characterized its transport using transporter-expressing systems, human cryopreserved hepatocytes, and Mrp2-deficient Eisai hyperbilirubinemic rats (EHBRs). Valsartan was significantly taken up into organic anion-transporting polypeptide (OATP) 1B1 (OATP2/OATP-C)- and OATP1B3 (OATP8)-expressing HEK293 cells. We also observed saturable uptake into human hepatocytes. Based on our estimation, the relative contribution of OATP1B1 to the uptake of valsartan in human hepatocytes depends on the batch, ranging from 20 to 70%. Regarding efflux transporters, the ratio of basal-to-apical transcellular transport of valsartan to that in the opposite direction in OATP1B1/MRP2 (multidrug resistance-associated protein 2) double transfected cells was the highest among the three kinds of double transfectants, OATP1B1/MRP2, OATP1B1/multi-drug resistance 1, and OATP1B1/breast cancer resistance protein-expressing MDCKII cells. We observed saturable ATP-dependent transport into membrane vesicles expressing human MRP2. We also found that the elimination of intravenously administered valsartan from plasma was markedly delayed, and the biliary excretion was severely impaired in EHBR compared with normal Sprague-Dawley rats. These results suggest that OATP1B1 and OATP1B3 as the uptake transporters and MRP2 as the efflux transporter are responsible for the efficient hepatobiliary transport of valsartan.

Topics: Adenosine Triphosphate; Angiotensin II Type 1 Receptor Blockers; Animals; Bile; Cell Line; Cell Membrane; Disease Models, Animal; Estrone; Hepatocytes; Humans; Hyperbilirubinemia; Liver-Specific Organic Anion Transporter 1; Male; Membrane Transport Proteins; Multidrug Resistance-Associated Protein 2; Multidrug Resistance-Associated Proteins; Organic Anion Transporters; Organic Anion Transporters, Sodium-Independent; Rats; Rats, Sprague-Dawley; Sincalide; Solute Carrier Organic Anion Transporter Family Member 1B3; Tetrazoles; Transfection; Valine; Valsartan

To illustrate the existence of bile regurgitation under stress condition, and explore the possible effects and related mechanism of changes of plasma cholecystokinin octapeptide (CCK-8) and intragastric pH on stress-induced bile regurgitation in rats.. (1) Changes in plasma CCK-8 and gastric bile concentration were respectively measured by using radioimmunoassay (RIA) method while simultaneously calculating gastric ulcer index (UI) and intragastric pH; (2) Each isolated gastric strips were suspended in a tissue chamber to record the contractile responses by polyphysiograph; (3) The responsiveness of gastric smooth muscle cells (SMCs) to sulfated cholecystokinin octapeptide (CCK-8S) were examined using fura-2-loaded microfluorimetric measurement of intracellular calcium concentration ([Ca(2+)]i); (4) The current of L-type calcium channels (I(CaL)) of SMCs were recorded by patch clamp techniques.. (1) Compared with the normal control group, plasma CCK-8 and gastric bile concentration significantly increased during stress (p<0.01) and both simultaneously reached the peak at the time point of 2 h after stress; UI and intragastric pH apparently increased (p<0.01); (2) Significant changes to CCK-8S were found in the mean contractile amplitude and frequency of circular muscle (CM) and longitudinal muscle (LM) of gastric antrum and pylorus; (3) CCK-8S-evoked significant increase in [Ca(2+)]i (p<0.01) could be suppressed by CCK-A receptor (CCK-AR) antagonist; whereas a small but significant increase was still elicited by CCK-8S under condition of the removal of extracellular calcium or by given nifidipine; (4) CCK-8S-intensified calcium current (I(CaL)) apparently inhibited by respective administration of nifidipine, Ca(2+)-ATPase inhibitors or calcium dependent chloride channel (I(Cl-Ca)) blocker (p<0.01).. Gastric mucosal damage induced by bile regurgitation is closely connected with gastric antrum and pylorus dysmotility evoked by CCK-8 during the stress. CCK-8S-evoked [Ca(2+)]i increase in gastric antrum and pylorus SMC depends on the release of intracellular calcium stores which activates L-type voltage-dependent calcium channels (VDCC) through the activation of calcium dependent chloride channels.

Topics: Animals; Bile; Calcium; Cholecystokinin; Digestive System; Disease Models, Animal; Female; Gastric Mucosa; Hydrogen-Ion Concentration; Male; Patch-Clamp Techniques; Peptide Fragments; Rats; Rats, Sprague-Dawley; Stomach Diseases; Ulcer

The recently proposed Inflammatory Reflex describes an interaction between the vagus nerve and peripheral macrophages, resulting in attenuation of proinflammatory cytokine release in response to systemic exposure to bacterial endotoxin. The purpose of this study was to determine whether a similar vagus/macrophage axis modulates the inflammatory responses in the colon in mice.. We assessed the Disease Activity Index (DAI), macroscopic and histologic damage, serum amyloid-P level, and myeloperoxidase activity in colitis induced by administration of dextran sodium sulfate (DSS) in healthy and vagotomized C57BL/6 and in mice deficient in macrophage-colony stimulating factor (M-CSF)-induced and in hapten-induced colitis. A pyloroplasty was performed in vagotomized mice.. DAI, macroscopic and histologic scores, myeloperoxidase activity, levels of serum amyloid-P, and colonic tissue levels of interleukin (IL)-1beta, IL-6, and tumor necrosis factor-alpha were increased significantly in vagotomized mice 5 days post-DSS and 3 days after hapten-induced colitis compared with sham-operated mice that received DSS or the hapten. Pretreatment with nicotine significantly decreased each of these markers in vagotomized mice with DSS colitis, and all markers except DAI and IL-6 in sham-operated DSS-treated mice. Conversely, hexamethonium treatment significantly increased each of these markers in the sham-operated DSS-treated mice. Vagotomy had no effect on the colitis in M-CSF-deficient mice.. The vagus nerve plays a counterinflammatory role in acute colitis via a macrophage-dependent mechanism, involving hexamethonium-sensitive nicotinic receptors. The identification of a counterinflammatory neural pathway would open new therapeutic avenues for treating acute exacerbations of inflammatory bowel disease.

Topics: Animals; Anticoagulants; Appetite Depressants; Dextran Sulfate; Dinitrofluorobenzene; Disease Models, Animal; Eating; Ganglionic Blockers; Ganglionic Stimulants; Hexamethonium; Inflammatory Bowel Diseases; Macrophage Colony-Stimulating Factor; Macrophages, Peritoneal; Male; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; Neural Inhibition; Nicotine; Pylorus; Sincalide; Vagotomy; Vagus Nerve

Major aspects of temporal lobe epilepsy (TLE) can be reproduced in mice following a unilateral injection of kainic acid into the dorsal hippocampus. This treatment induces a non-convulsive status epilepticus and acute lesion of CA1, CA3c and hilar neurons, followed by a latent phase with ongoing ipsilateral neuronal degeneration. Spontaneous focal seizures mark the onset of the chronic phase. In striking contrast, the ventral hippocampus and the contralateral side remain structurally unaffected and seizure-free. In this study, functional and neurochemical alterations of the contralateral side were studied to find candidate mechanisms underlying the lack of a mirror focus in this model of TLE. A quantitative analysis of simultaneous, bilateral EEG recordings revealed a significant decrease of theta oscillations ipsilaterally during the latent phase and bilaterally during the chronic phase. Furthermore, the synchronization of bilateral activity, which is very high in control, was strongly reduced already during the latent phase and the decrease was independent of recurrent seizures. Immunohistochemical analysis performed in the contralateral hippocampus of kainate-treated mice revealed reduced calbindin-labeling of CA1 pyramidal cells; down-regulation of CCK-8 and up-regulation of NPY-labeling in mossy fibers; and a redistribution of galanin immunoreactivity. These changes collectively might limit neuronal excitability in CA1 and dentate gyrus, as well as glutamate release from mossy fiber terminals. Although these functional and neurochemical alterations might not be causally related, they likely reflect long-ranging network alterations underlying the independent evolution of the two hippocampal formations during the development of an epileptic focus in this model of TLE.

Topics: Action Potentials; Animals; Brain Chemistry; Calbindins; Chronic Disease; Disease Models, Animal; Down-Regulation; Electroencephalography; Epilepsy; Epilepsy, Temporal Lobe; Functional Laterality; Galanin; Hippocampus; Kainic Acid; Mice; Mossy Fibers, Hippocampal; Nerve Degeneration; Neural Pathways; Neuropeptide Y; Neurotoxins; Pyramidal Cells; S100 Calcium Binding Protein G; Sincalide; Status Epilepticus; Theta Rhythm; Up-Regulation

Systemic administration of cholecystokinin (CCK) fragments produces anxiogenic effects. The dorsal periaqueductal gray (dPAG) has been related to anxiety and panic reactions. The objective of this study was to investigate a possible anxiogenic effect of CCK-8 microinjected into the dPAG. At 10 min after the last microinjection (0.5 microl) into the dPAG male Wistar rats (N=7-17) were tested in the elevated plus-maze, an animal model of anxiety. The following treatments were tested alone or in combination: sulfated CCK-8 (CCK-8s, 0.5-1 microg), PD 135158 (N-methyl-D-glucamine, 0.1 microg), a CCK-2 receptor antagonist, lorglumide (0.1-0.3 microg), a CCK-1 receptor antagonist. In addition, Fos immunohistochemistry was performed in rats (n=3-4) treated with CCK-8s (1 microg) alone or in combination with PD 135158 (0.1 microg). CCK-8s produced anxiogenic-like effect, decreasing the percentage of time spent in open arm (saline=30.3+/-6.6, CCK 0.5 microg=15.2+/-1.8; CCK 1 microg=14.6+/-2.1). This effect was prevented by pretreatment with PD 135158, but not by lorglumide. CCK-8s injected into the dPAG induced Fos immunoreactivity in several brain areas related to defensive behavior, including the PAG, median, and dorsal raphe nuclei, superior colliculus, lateral septal nuclei, medial hypothalamus, and medial amygdala. This effect was also prevented by pretreatment with PD 135,158. These results suggest that CCK-8s, acting on CCK-2 receptors, may modulate anxiety reactions in the dPAG.

Topics: Analysis of Variance; Animals; Anti-Anxiety Agents; Anxiety; Appetite Depressants; Cell Count; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Combinations; Drug Interactions; Hormone Antagonists; Immunohistochemistry; Indoles; Male; Maze Learning; Meglumine; Microinjections; Neurons; Periaqueductal Gray; Proglumide; Proto-Oncogene Proteins c-fos; Rats; Rats, Sprague-Dawley; Receptor, Cholecystokinin B; Sincalide; Superior Colliculi; Time Factors

Cholecystokinin-octapeptide (CCK-8) has been shown to possess an acute thermogenic and hyperthermic action when given intracerebroventricularly in slightly restrained rats. To substantiate the febrile nature of that hyperthermia freely moving animals should be used and together with body core temperature, at least one behavioral parameter, such as general activity, should also be recorded. In the present studies, Wistar rats (N=34) exposed to thermoneutral (26-28 degrees C) or cold (4 degrees C) ambient temperature and to a 12:12-h light/darkness schedule were infused intracerebroventricularly with CCK-8 or prostaglandin E1 (PGE1) for several days using ALZET minipump and changes in body core temperature and general activity were recorded by biotelemetry (Minimitter). In rats exposed to a thermoneutral ambient temperature, low doses of CCK-8 induced slight but significant rises of day minima of circadian body temperature rhythm (CBTR) and with a high dose (1 microg/h) of the peptide--infused either at thermoneutrality or during cold exposure--an increase of acrometron could also be recorded. All of these changes were observed only during the first 2-4 days of 7-day-long infusions. Intracerebroventricular infusion of PGE1 administered at thermoneutrality in a dose of 1 microg/h for 7 days induced a marked rise in body core temperature with a disappearance of CBTR in some rats for 2-3 days or with rises of day minima/acrometron in others. General activity--running parallel with CBTR in periods without infusions--tended to be decreased when core temperature rose during the first couple of days of intracerebroventricular infusion of higher doses of CCK-8 or of PGE1. The decreased general activity--one component of sickness behavior--together with an increased body core temperature found in the present study, supports the view that they are components of a genuine fever induced by the central effect of the two mediators used.

Topics: Alprostadil; Animals; Body Temperature Regulation; Circadian Rhythm; Disease Models, Animal; Female; Fever; Hyperthermia, Induced; Infusion Pumps, Implantable; Injections, Intraventricular; Motor Activity; Pyrogens; Rats; Rats, Wistar; Restraint, Physical; Sincalide

The pharmacological profile of the new CCK1 receptor antagonist IQM-97,423, (4aS,5R)-2-benzyl-5-(tert-butylaminocarbonyl-tryptophyl)amino-1,3-dioxoperhydropyrido-[1,2-c]pyrimidine, was examined in in vitro and in vivo studies and compared with typical CCK1 antagonists such as devazepide and lorglumide. IQM-97,423 showed a high affinity at [3H]-pCCK8-labeled rat pancreatic CCK1 receptors, and was virtually devoid of affinity at brain CCK2 receptors. IQM-97,423 antagonized CCK8S-stimulated alpha-amylase release from rat pancreatic acini with a potency similar to devazepide and much higher than lorglumide. In the guinea pig isolated longitudinal muscle-myenteric plexus preparation, IQM-97,423 produced a full antagonism of the contractile response elicited by CCK8S and a weaker effect on the contraction elicited by CCK4, suggesting a selective antagonism at CCK1 receptors. The protective effect of IQM-97,423 and devazepide was tested in two models of acute pancreatitis in rats, induced by injection of cerulein or by combined bile and pancreatic duct obstruction. The new compound fully prevented the cerulein-induced increase in plasma pancreatic enzymes and in pancreas weight with a potency similar to devazepide. In common bile-pancreatic duct ligature-induced acute pancreatitis, IQM-97,423 partially prevented, like devazepide, the increase in plasma pancreatic enzyme activity and in pancreas weight. Consequently, the pyridopyrimidine derivative IQM-97,423 is a potent and highly selective CCK1 receptor antagonist with preventive effects in two experimental models of acute pancreatitis and a potential therapeutic interest.

Topics: Acute Disease; alpha-Amylases; Animals; Binding, Competitive; Cerebral Cortex; Cholecystokinin; Devazepide; Disease Models, Animal; Guinea Pigs; Ileum; In Vitro Techniques; Male; Mice; Muscle Contraction; Muscle, Smooth; Myenteric Plexus; Neuromuscular Junction; Pancreatitis; Peptide Fragments; Proglumide; Pyrimidinones; Rats; Rats, Wistar; Receptor, Cholecystokinin A

We examined the roles of cholecystokinin (CCK)-2 receptors in the regulation of pepsinogen secretion in the CCK-1 receptor deficient Otsuka Long-Evans Tokushima Fatty (OLETF) rats. Pepsinogen secretion was determined in fasted acute fistula OLETF and control Long-Evans Tokusima Otsuka (LETO) rats. Pepsinogen secretion in OLETF rats under basal conditions as well as in response to CCK-8 stimulation was significantly higher than that in LETO rats. CCK-1 receptor specific agonist ARL 15849 was unable to stimulate pepsinogen secretion in OLETF rats, whereas it elicited pepsinogen secretion in LETO rats to levels similar to those obtained with equimolar CCK-8 stimulation. CCK-2 receptor antagonist reduced basal pepsinogen secretion and completely abolished CCK-8-stimulated pepsinogen output in OLETF rats, whereas in LETO rats, it reduced basal pepsinogen secretion but augmented CCK-8-stimulated pepsinogen output. CCK-1 receptor antagonist loxiglumide also greatly decreased CCK-8-stimulated pepsinogen secretion in OLETF rat, which indicates that loxiglumide is not a specific CCK-1 receptor antagonist. Intravenous infusion of somatostatin antagonist significantly increased CCK-8-stimulated pepsinogen secretion in LETO rats, whereas it had no significant influence on CCK-8-stimulated pepsinogen secretion in OLETF rats. These results indicate that CCK-8 stimulates pepsinogen secretion via CCK-2 receptors in CCK-1 receptor deficient OLETF rats and that the higher CCK-8-stimulated as well as basal pepsinogen secretion in OLETF rats might result from an elimination of tonic inhibition by somatostatin that is released from D cells through mainly CCK-1 receptors.

Topics: Animals; Disease Models, Animal; Gastrins; Male; Pepsinogen A; Probability; Rats; Rats, Inbred OLETF; Rats, Long-Evans; Receptor, Cholecystokinin A; Receptors, Cholecystokinin; Reference Values; Risk Factors; Sensitivity and Specificity; Sincalide; Somatostatin; Species Specificity; Statistics, Nonparametric

The neuropeptide cholecystokinin (CCK) has been implicated in fear and anxiety. CCK is found in the CNS in several molecular forms such as the tetrapeptide (CCK-4) and, mainly, the sulfated octapeptide (CCK-8s) fragments. Administration of CCK-4 induces panic attacks in humans and increases the expression of different anxiety-related behaviors in laboratory animals. The effects of CCK-8s on fear and anxiety are less straightforward and seem to be influenced, among other factors, by the route of the peptide administration and the animal model employed. In other to further investigate the role of CCK-8s in fear and anxiety, in the present study we analyzed the effect of CCK-8s in male Wistar rats submitted to the elevated T-maze. This animal model of anxiety was developed in order to separate generalized anxiety (inhibitory avoidance) and panic-like (escape) responses in the same rat. The effect of CCK-8s in this test was also investigated after injection of the peptide into the dorsal periaqueductal gray (DPAG). This brainstem area is rich in CCK receptors and has consistently been implicated in the mediation of fear and anxiety responses. The results showed that both the intraperitoneal and intra-DPAG injections of CCK-8s potentiated one-way escape behavior, suggesting a panicogenic action. In contrast, the injection of the CCK2 receptor antagonist CR2945 inhibited the expression of this behavior, a panicolytic-like effect. Therefore, the elevated T-maze, in contrast to other animal models of anxiety, can detect the anxiety-eliciting effects of CCK-8s both after its systemic and central administration. Also, the results provide further evidence about the involvement of a CCK-mediated mechanism within the DPAG in the regulation of panic-related defensive behaviors.

Topics: Animals; Anxiety; Behavior, Animal; Benzodiazepines; Disease Models, Animal; Fear; Infusion Pumps; Injections, Intraperitoneal; Male; Maze Learning; Microinjections; Neurons; Nootropic Agents; Panic; Periaqueductal Gray; Rats; Rats, Wistar; Sincalide

Although ethanol abuse is the major etiologic factor in the development of acute and chronic pancreatitis, the mechanisms of ethanol effects to cause pancreatitis are poorly understood. The major reason for the lack of progress is the relative lack of animal models that reproduce the deleterious effects of ethanol on the pancreas that are observed in human disease. We propose that the effect of ethanol on the pancreas is due to its ability to sensitize animals and humans to the potentially injurious effects of other stimuli. We have developed models of ethanol-induced acute and chronic pancreatitis in rats as well as pancreatic acinar cells in primary culture demonstrating that ethanol sensitizes the pancreas to the inflammatory, cell death, and fibrosing responses caused by cholecystokinin (CCK). Our results indicate that the ethanol-sensitized inflammatory response is the key or trigger event for the development of the other pathologic responses in both acute and chronic pancreatitis, such as cell death, intracellular digestive enzyme activation, and fibrosis. These findings suggest that experimental strategies designed to reveal the modulating effects of ethanol on the mechanisms underlying the inflammatory, cell death, and fibrosing responses stimulated by CCK will provide the key information needed to understand how ethanol abuse causes pancreatitis.

Topics: Animals; Disease Models, Animal; Ethanol; Humans; In Vitro Techniques; NF-kappa B; Pancreas; Pancreatitis, Alcoholic; Rats; Sincalide; Transcription Factor AP-1

We investigated the effects of increasing concentrations of cholecystokinin octapeptide (CCK-8) on the exocrine pancreas of a new model of type 2 diabetic rats due to the partial protection exerted by nicotinamide against the beta-cytotoxic effect of streptozotocin. CCK-8, administered for 8 successive days, exerted a biphasic action on the growth of the pancreas in non-diabetic and type 2 diabetic rats; however, the latter were less sensitive to CCK-8. Similar results were obtained in vitro by measuring the uptake of 5-bromo-2'-deoxyuridine (BrdU) in cultured isolated acinar cells. This effect was completely blocked by 3S(-)(N'-2,3-dihydro-1-methyl-2-oxo5-phenyl-1H-1,4-benzo-diazepin-3-yl)-1H-indole-2-carboxamide (L 364,718; a CCK(1) receptor antagonist) but not by (3R)-3[N'-(3-methylphenyl)ureido]-1,3-dihydro-1-methyl-5-phenyl-2H1,4-benzo-diazepin-2-one (L 365,260; a CCK(2) receptor antagonist), suggesting a direct effect via CCK(1) receptors. Binding studies showed that these effects were mediated by a single class of low-affinity CCK(1) receptors in diabetic rats and two classes of CCK-8 binding sites (with high and low affinity) in non-diabetic rats. Thus, in our new type 2 diabetes model, the loss of sensitivity of the pancreas to CCK-8 could be attributed to the loss of CCK(1) receptors of high affinity.

Topics: Animals; Diabetes Mellitus, Type 2; Disease Models, Animal; Dose-Response Relationship, Drug; Male; Organ Size; Pancreas; Rats; Rats, Wistar; Receptors, Cholecystokinin; Sincalide

Cells respond to stress by upregulating the synthesis of cytoprotective heat shock proteins (HSPs) and antioxidant enzymes. The aim of this study was to compare the effects of cold (CWI) or hot water immersion (HWI) stress on three different acute pancreatitis models (cholecystokinin octapeptide (CCK), sodium taurocholate (TC), and L-arginine (Arg)). We examined the levels of pancreatic HSP60, HSP72, and antioxidants after the water immersion stress. Male Wistar rats were injected with CCK, TC, or Arg at the peak level of pancreatic HSP synthesis, as determined by Western blot analysis. HWI significantly elevated HSP72 expression and CWI significantly increased HSP60 expression in the pancreas. Water immersion stress decreased the levels of pancreatic antioxidants. CWI and-HWI pretreatment ameliorated most of the examined laboratory and morphological parameters of CCK-induced pancreatitis. CWI pretreatment decreased pancreatic edema and the serum amylase level; however, the morphological damage was more severe in TC-induced acute pancreatitis. Overall, CWI and HWI pretreatment only decreased the serum cytokine concentrations in Arg-induced pancreatitis. CWI and HWI resulted in differential induction of pancreatic HSP60 and HSP72 and the depletion of antioxidants. The findings suggest the possible roles of HSP60 and (or) HSP72 (but not that of the antioxidant enzymes) in the protection against CCK- and TC-induced acute pancreatitis. Unexpectedly, CWI pretreatment was detrimental to the morphological parameters of TC-induced pancreatitis. It was demonstrated that CWI and HWI pretreatment only influenced cytokine synthesis in Arg-induced pancreatitis.

Topics: Acute Disease; Amylases; Animals; Antioxidants; Blotting, Western; Body Weight; Chaperonin 60; Cytokines; Disease Models, Animal; Heat-Shock Proteins; HSP72 Heat-Shock Proteins; Immersion; Lipase; Male; Microscopy, Electron; Organ Size; Pancreas; Pancreatitis; Rats; Rats, Wistar; Sincalide; Stress, Physiological; Trypsinogen

A series of our studies have shown that formation of cholesterol-supersaturated bile in patients with cholesterol gallstone disease is causatively related to decreased gallbladder contractility and mucin hypersecretion by the gallbladder. Supersaturated bile may modify the composition of gallbladder membranes so that the transduction of smooth muscle regulatory signals is impaired, and it may enhance the inflammation-induced mucin secretion by the gallbladder. To achieve a better understanding of the mechanism by which supersaturated bile impairs the contractility, we studied changes in the expression levels of gallbladder cholecystokinin (CCK-A) receptor messenger ribonucleic acid (mRNA) in prairie dogs fed a high-cholesterol diet. Levels of pathobiological determinants in arachidonate metabolism which are important for mucin secretion were also measured in their bile. Adult male prairie dogs were randomly assigned to receive either a semisynthetic diet (SSD) or an SSD plus 1.2% cholesterol (a high-cholesterol diet) for 2-, 4-, and 6-week periods. The contractile force in response to CCK-octapeptide (CCK-8) was measured by using gallbladder muscle strips. The mRNA levels of the CCK-A receptor were determined by reverse-transcription polymerase chain reaction (RT-PCR). Parallel to the increase in the cholesterol saturation index, the contractile responses to CCK-8 decreased in the animals fed a high-cholesterol diet for 4 weeks and markedly decreased in the animals with gallstone formation. However, in contrast to the decreased contractility, the steady-state mRNA levels of the gallbladder CCK-A receptor were significantly increased in the animals fed a high-cholesterol diet in comparison with the corresponding control animals. In the bile, a high-cholesterol diet caused an increase in the proportion of arachidonyl-phosphatidylcholine species, where phospholipase A(2) activity, prostaglandin E(2), and mucin concentrations were increased parallel to the feeding period. Up-regulation of the CCK-A receptor mRNA in the gallbladder of animals fed a high-cholesterol diet associated with decreased contractility may be due to an impairment of CCK signaling related to increased membrane cholesterol contents and its related reaction of biological compensation in order to increase the receptor concentration. The results of the present study suggest that in prairie dogs fed a high-cholesterol diet both a decrease in gallbladder contractility related to impairment of

Topics: Animals; Arachidonic Acid; Bile; Blotting, Northern; Body Weight; Cholelithiasis; Cholesterol; Cholesterol 7-alpha-Hydroxylase; Cholesterol, Dietary; Crystallization; Dinoprostone; Disease Models, Animal; Fatty Acids; Gallbladder; Gene Expression; Hydroxymethylglutaryl CoA Reductases; Lipids; Liver; Male; Microsomes, Liver; Mucins; Muscle Contraction; Muscles; Phosphatidylcholines; Phospholipases A; Receptor, Cholecystokinin A; Receptors, Cholecystokinin; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sciuridae; Sincalide

The aim of our study was to investigate the role of cholecystokinin-8 (CCK-8), which is able to induce the synthesis of nerve growth factor (NGF), in the joint inflammation of carrageenan-injected rats.. Adult rats were injected in the ankle joint with carrageenan, with or without CCK-8 or a CCK receptor antagonist (proglumide), and tissue swelling, NGF levels and NGF mRNA expression were assessed.. Expression of NGF and NGF mRNA increased transiently after carrageenan injection. This effect was not altered by CCK-8 injection but was inhibited by the CCK receptor antagonist. The decrease in NGF level after treatment with the antagonist was concurrent with an increase in paw swelling.. The results demonstrate that, whereas CCK-8 has no anti-inflammatory action in carrageenan-injected animals, proglumide induces a worsening of inflammation and reduces the expression of both NGF and NGF mRNA in inflamed ankle joints. Our data point to a regulatory action of CCK-8 on NGF synthesis during acute synovitis and suggest a role for NGF in the healing phase of inflammation.

Topics: Animals; Arthritis, Experimental; Carrageenan; Disease Models, Animal; Drug Interactions; Enzyme-Linked Immunosorbent Assay; Female; Joints; Nerve Growth Factor; Proglumide; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sincalide

Many in vitro studies in the choledochoduodenal junction of the guinea pig have shown that cholecystokinin (CCK) contracts the sphincter of Oddi (SO). This study, using the choledochal sphincter of the guinea pig as the SO, evaluates the hypothesis that effects of CCK on the SO were mediated by nitric oxide (NO).. Spontaneous motility and effects of CCK on the choledochal sphincter were recorded using a constant-perfusion technique, and direct measurement of NO release using a specific NO sensor was performed at the same time.. CCK-8 decreased the phasic wave amplitude of the choledochal sphincter, and increased NO release. N(G)-L-arginine-methyl-ester (L-NAME), an inhibitor of NO synthase, increased the spontaneous motility and converted the CCK-induced inhibitory response into an excitatory response. L-NAME also reduced NO release and abolished the increase of NO that had been caused by CCK-8. These effects were reduced by treatment with L-arginine (L-Arg). L-Arg application enhanced NO release, and recovered the increase of NO by CCK-8.. These studies demonstrate that CCK relaxes the choledochal sphincter and this relaxant response is mediated by NO.

Topics: Animals; Common Bile Duct; Culture Techniques; Disease Models, Animal; Gallbladder Emptying; Gastrointestinal Agents; Guinea Pigs; Male; Monitoring, Physiologic; NG-Nitroarginine Methyl Ester; Nitric Oxide; Reference Values; Sincalide; Sphincter of Oddi

The Koletsky ("corpulent) obese rat is homozygous for an autosomal recessive mutation of the leptin receptor (Lepr) that results in hyperphagia, obesity, and hyperlipidemia. Unlike the Lepr mutation that characterizes the fatty Zucker rat (Lepr(fa)), the Koletsky mutation (Lepr(fak)) is null. Because the Lepr(fak) mutation is null, exogenous leptin should have no effect on body weight or food intake in fa(k)/fa(k) rats. We confirmed that prediction: murine leptin, administered into the third ventricle for 5 consecutive days, did not affect daily food intake or body weight in fa(k)/fa(k) rats but produced dose-related inhibitions of food intake and body weight in +/+ and +/fa(k) rats. Although fa(k)/fa(k) rats did not respond to leptin, their response to CCK-8 (4 microg/kg ip) injected before 30-min test meals of 10% sucrose was not different from that of +/+ or +/fa(k) rats. These results demonstrate that the fa(k)/fa(k) rat is a good model in which to analyze the controls of food intake, energy expenditure, and energy storage in the absence of leptin effects.

Topics: Animals; Carrier Proteins; Dietary Sucrose; Disease Models, Animal; Eating; Injections, Intraventricular; Leptin; Obesity; Rats; Rats, Mutant Strains; Receptors, Cell Surface; Receptors, Leptin; Satiation; Sincalide; Weight Gain; Weight Loss

We examined the influence of 2 gut hormones involved in the enhancement of pancreatic exocrine secretion, secretin and cholecystokinin (CCK), in the exacerbation of pancreatitis. We also examined the role of the vagal system, which was considered to be a transmission route for these hormones. Our model of pancreatitis in the rat was prepared by pancreatic bile duct ligation (PBDL), which simultaneously ligated the pancreatic duct and the common bile duct. Serum amylase activity and histopathological changes in the pancreas were used as indices of pancreatitis. We also measured the volume of pancreatic juice, as well as the amylase activity and protein level of the pancreatic juice, as indices of increased pancreatic exocrine secretion. Two gut hormones were given 6 times at 1-h intervals. Administration of secretin (1-3 microg/kg, s.c.) did not influence serum amylase activity in rats with PBDL-induced pancreatitis. However, food stimulation and administration of CCK-8 (1 microg/kg, s.c.) increased serum amylase activity and promoted vacuolation of the pancreatic acinar cells in rats with PBDL-induced pancreatitis. Administration of atropine (3 mg/kg, s.c.) or a CCK1-receptor antagonist, Z-203 (0.1 mg/kg, i.v.), inhibited food-stimulated or CCK-8-induced (1 microg/kg, s.c.) enhancement of pancreatic exocrine secretion and exacerbation after the development of PBDL-induced pancreatitis. These results suggest that not secretin, which regulates the volume of pancreatic juice, but CCK, which regulates the secretion of pancreatic enzymes via the vagal system, plays an essential role in food-stimulated exacerbation after the development of pancreatitis.

Topics: Amylases; Animals; Bile Ducts; Cholecystokinin; Disease Models, Animal; Fasting; Ligation; Male; Pancreas; Pancreatitis; Rats; Secretin; Sincalide; Vagus Nerve

To study the regulatory effect of Erbao granules (EBG) on central and peripheral brain-gut peptide in juvenile animal model of anorexia.. Juvenile rat model of anorexia was established by imitating the major cause of infantile anorexia and treated with EBG. The cholocystokinin-octapeptide (CCK-8) and beta-endorphin (beta-EP) concentration in hypothalamus, antrum pyloricum and peripheral blood were examined by radioimmunoassay.. CCK-8 concentration in hypothalamus and plasma in the model rats increased (P < 0.05), while blood beta-EP concentration decreased (P < 0.05). After EBG treatment, the CCK-8 concentration normalized and beta-EP increased significantly.. EBG could reduce the central and peripheral CCK-8 and increase beta-EP secretion significantly in the juvenile anorexia model.

Topics: Animals; Anorexia; beta-Endorphin; Disease Models, Animal; Drugs, Chinese Herbal; Female; Gastric Mucosa; Hypothalamus; Male; Rats; Rats, Sprague-Dawley; Sincalide

Although alcoholism is a major cause of pancreatitis, the pathogenesis of this disorder remains obscure. Failure to produce experimental alcoholic pancreatitis suggests that ethanol may only increase predisposition to pancreatitis. This study sought to develop a model of ethanol pancreatitis by determining if an ethanol diet sensitizes rats to pancreatitis caused by cholecystokinin octapeptide (CCK-8).. Rats were fed intragastrically either control or ethanol diet for 2 or 6 weeks. The animals were then infused for 6 hours with either saline or CCK-8 at a dose of 3000 pmol. kg(-1). h(-1), which by itself did not induce pancreatitis. The following parameters were measured: serum amylase and lipase levels, pancreatic weight, inflammatory infiltration, number of apoptotic acinar cells, pancreatic messenger RNA (mRNA) expression of cytokines and chemokines, and nuclear factor (NF)-kappaB activity.. All measures of pancreatitis, as well as NF-kappaB activity and mRNA expression for tumor necrosis factor alpha, interleukin 6, monocyte chemotactic protein 1, macrophage inflammatory protein 2, and inducible nitric oxide synthase, were significantly increased only in rats treated with ethanol plus CCK-8.. An ethanol diet sensitizes rats to pancreatitis caused by CCK-8. The combined action of ethanol and CCK-8 results in NF-kappaB activation and up-regulation of proinflammatory cytokines and chemokines in the pancreas. These mechanisms may contribute to the development of alcoholic pancreatitis.

Topics: Amylases; Animals; Apoptosis; Chemokines; Cytokines; Disease Models, Animal; Ethanol; Lipase; Male; NF-kappa B; Nuclear Proteins; Pancreas; Pancreatitis, Alcoholic; Rats; Rats, Wistar; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sincalide

Perinatal malnutrition and growth retardation at birth are suggested to be important risk factors for the development of overweight and syndrome X in later life. Underlying mechanisms are unknown. Body weight and food intake are regulated, e.g. by hypothalamic neuropeptidergic systems which are thought to be highly vulnerable to persisting malorganization due to perinatal malnutrition. To investigate possible consequences for hypothalamic cholecystokinin-8S (CCK-8S) in the offspring, pregnant Wistar rats were fed an 8% protein diet during pregnancy and lactation (low-protein group; LP) while control mothers (CO) received a 17% protein isocaloric standard diet. LP offspring displayed underweight at birth (P < 0.05) and during suckling (P < 0.001), while leptin levels were not altered. At weaning, under basal conditions CCK-8S was decreased in LP offspring in the paraventricular hypothalamic nucleus and arcuate hypothalamic nucleus (P < 0.05), as well as in the dorsomedial hypothalamic nucleus, lateral hypothalamic area and ventromedial hypothalamic nucleus (P < 0.01). In summary, these data indicate (1) an inhibition of the satiety peptide CCK-8S in main regulators of body weight and food intake in low-protein malnourished newborn rats; (2) no direct relationship of hypothalamic CCK-8S to circulating leptin at this age; and (3) no neurochemical signs of hypothalamic CCKergic dysregulation in this animal model at the age of weaning.

Topics: Animals; Animals, Newborn; Birth Weight; Body Weight; Dietary Proteins; Disease Models, Animal; Eating; Female; Hypothalamus; Insulin Resistance; Male; Maternal-Fetal Exchange; Nutrition Disorders; Obesity; Pregnancy; Pregnancy Complications; Rats; Rats, Wistar; Sincalide

We compared pancreatic exocrine secretion in 5-month-old WBN/Kob rats, a model of chronic pancreatitis, with that in Wistar rats of the same age in a conscious state. Basal pancreatic secretion and pancreatic wet weight in WBN/Kob rats were lower than the values for Wistar rats. There was no difference in plasma cholecystokinin (CCK) concentration between the two types of rats. When CCK-8 was intravenously administered, the stimulation of pancreatic protein secretion in WBN/Kob rats was weaker than that in Wistar rats. When bile and pancreatic juice were diverted from the duodenum, the resulting increase in the plasma CCK concentration was similar in both types of rats, but stimulation of the volume and protein output of pancreatic juice in WBN/Kob rats was weaker than that in Wistar rats. In addition, WBN/Kob rats exhibited little increase in pancreatic wet weight because of this diversion. When secretin was intravenously administered, the stimulation of fluid secretion in WBN/ Kob rats was also weaker than that in Wistar rats. The binding of CCK-8 to pancreatic membrane fractions in WBN/Kob rats was much weaker than that in Wistar rats. Histological findings in WBN/Kob rat pancreas showed proliferation of fibrous tissue and atrophy of acinar cells. In conclusion, pancreatic exocrine secretion in response to the gastrointestinal hormones, CCK and secretin, was lower in WBN/Kob rats than in Wistar rats. These findings suggest that the hyposecretion of pancreas in WBN/Kob rats is hyporeaction of pancreatic membrane to gastrointestinal hormones.

Topics: Animals; Bile; Cholecystokinin; Chronic Disease; Disease Models, Animal; Male; Pancreas; Pancreatic Juice; Pancreatitis; Proteins; Rats; Rats, Wistar; Secretin; Sincalide

Human astrocytic tumors grow into the normal brain parenchyma either as localized tumors, or as highly diffuse neoplasms. The diffuse phenotype relates to a specific sub-type of neoplastic astrocytes with a high motility and invasion capacity. Motility features refer to locomotion while invasion features refer to protease secretion. Our data reveal that several peptides belonging to the gastrin/cholecystokinin peptide class are able to significantly (and in certain cases very significantly) modify the level of tumor growth (at the level of cell proliferation and/or cell death), of motility and of invasion in various experimental models of human astrocytic tumors. We are synthesizing various gastrin/cholecystokinin-related peptides in order to develop clinical applications with which we want to inhibit astrocytic tumor growth, individual neoplastic astrocytic motility and the invasion of the normal brain parenchyma.

Topics: Animals; Astrocytoma; Biomarkers, Tumor; Brain Neoplasms; Disease Models, Animal; Drug Evaluation, Preclinical; Gastrins; Humans; Mice; Sincalide

This study was conducted to determine what, if any, role L-NAME (inhibitor of nitric oxide synthase) plays in the behavioral effects induced by sulfated cholecystokinin octapeptide CCK-8) and cholecystokinin tetrapeptide (CCK-4) in adult male rats. The motility, stereotypy, anxiety, extinction of conditioned avoidance responses and recall of passive avoidance behavior were estimated. CCK-8 (but not CCK-4) injected intracerebroventricularly (icv) at the dose 0.1 nmole decreased of locomotor activity in the "open field" test. Administration of CCK-8 intensified stereotypy evoked by apomorphine (1 mg/kg, i.p.). The CCK-4 was ineffective in this test. Both, CCK-8 and CCK-4 did not make any significant differences in passive avoidance behavior. Examine the influence of CCK-8 and CCK-4 on the extinction of conditioned avoidance responses (CAR) proved that both peptide tended to facilitate extinction of CAR's. CCK-8 and CCK-4 induced anxiogenic-like effect in the elevated 'plus' maze behavior. Application of L-NAME alone (50 nmole,-icv) decreased of motility and stereotypy behavior in control rats. It was ineffective in a passive avoidance behavior and extinction of CAR's. In elevated 'plus' maze behavior injection of L-NAME, similarly to cholecystokinin, induced anxiogenic-like effect. L-NAME induced of motility decreases in the "open field" test were blocked by injection of CCK-8 and CCK-4. Our results indicate that observed behavioral activity of CCK-8 and CCK-4 (except of influence on motility) is probably independent of NO concentration in the brain.

Topics: Analysis of Variance; Animals; Behavior, Animal; Brain; Disease Models, Animal; Dopamine Agents; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide Synthase; Rats; Rats, Wistar; Sincalide; Tetragastrin

Psammomys obesus fed a high-calorie diet develops a NIDDM-like syndrome. The use of reverse-phase high-performance liquid chromatography (HPLC) to study Psammomys insulin biosynthesis and release revealed a very delayed elution time for the Psammomys insulin peak appearing near the position of human proinsulin. This unusual peak was initially thought to represent partially processed insulin on the basis of its molecular size and susceptibility to trimming by carboxypeptidase B (CpB). However, the findings of an active carboxypeptidase E (CpE) enzyme and the normal amidated forms of gastrin and cholecystokinin octapeptide (CCK-8) in Psammomys tissues were inconsistent with CpE-related aberrant processing of insulin. Moreover, amino acid sequencing of the delayed peak of Psammomys insulin revealed fully processed insulin with amino acid sequence as predicted by the cDNA. The unique presence of a B-30 phenylalanine residue, resulting in an increased hydrophobicity of the insulin molecule, probably underlies the marked delay in elution time on HPLC. The unusual structure of Psammomys insulin does not appear to contribute to the proinsulinemia observed in diabetic Psammomys since the HPLC-purified molecule did not inhibit PC1 and PC2 convertase activities in an in vitro assay.

Topics: Amino Acid Sequence; Animals; Base Sequence; Blotting, Western; Carboxypeptidases; Chromatography, High Pressure Liquid; Diabetes Mellitus, Type 2; Diet; Disease Models, Animal; DNA Primers; Furin; Gastrins; Gerbillinae; Humans; Insulin; Islets of Langerhans; Molecular Sequence Data; Pituitary Gland; Polymerase Chain Reaction; Proinsulin; Protein Precursors; Rats; Rats, Sprague-Dawley; Sincalide; Subtilisins

Activated leukocytes and cytokines have important roles in the multi-system involvement during acute pancreatitis. The changes in the serum level of tumor necrosis factor-a (TNF-alpha) and interleukin-6 (IL-6) over time were investigated in two experimental acute pancreatitis models in rats. Mild edematous pancreatitis was induced with an overdose of cholecystokinin octapeptide (CCK-8), while a severe hemorrhagic form of pancreatitis was induced by ligation of the common bilio-pancreatic duct. The rats were examined 2, 4, 8, 16, 24 and 48 h after pancreatitis induction. The severity of the inflammation was assessed by measurement of the serum amylase activity, quantification of the edema, and histological examination. Serum TNF-alpha and IL-6 were determined by bioassay, using the TNF-sensitive WEHI 164 and the IL-6-dependent B9 cell lines, respectively. In CCK-8-induced acute pancreatitis, the pancreatic weight/body weight ratio (pw/bw) and amylase level were significantly elevated at 2 h, and the maximum levels were observed at 4 h (8.19 +/- 1.13 mg/g and 69.4 +/- 12.8 x 10(3) U/ml, respectively). Both parameters subsequently decreased continuously during the observation period. The serum IL-6 level was significantly increased at 4 h relative to the controls (123.3 +/- 5.8 vs 37.5 +/- 15 pg/ml), and then decreased continuously. In this model, only a moderate level of serum TNF-alpha was observed at 2 h. In the biliary type of acute pancreatitis, the ratio pw/bw increased continuously during the study and reached the maximum level at 48 h relative to the sham-operated control (8.8 +/- 1.4 vs 5.3 +/- 0.8 mg/g). The serum amylase level was significantly elevated at 2 h (43.2 +/- 13 x 10(3) U/ml), but then decreased continuously. The serum IL-6 reached its maximum level at 16 h (3800 +/- 447 pg/ml). In this model, increased TNF-alpha levels (75-300 U/ml) were measured 8, 16 and 24 h after pancreatitis induction. The results led to correlations between the serum IL-6 levels and the biochemical and morphological severity of acute pancreatitis in both experimental models. The data suggest that IL-6 and TNF-alpha may participate in the pathogenesis of these types of acute pancreatitis.

Topics: Acute Disease; Amylases; Animals; Body Weight; Cholestasis; Disease Models, Animal; Interleukin-6; Laparotomy; Ligation; Male; Organ Size; Pancreatitis; Rats; Rats, Wistar; Sincalide; Time Factors; Tumor Necrosis Factor-alpha

Pancreatic exocrine hypofunction is markedly deteriorated during acute exacerbation in a rat model with chronic pancreatitis.. Little is known about pancreatic exocrine function during acute exacerbation in patients with chronic pancreatitis. We investigated changes in pancreatic exocrine function after inducing acute pancreatitis in an animal model of spontaneous chronic pancreatitis.. WBN/Kob rats with chronic pancreatitis sequentially underwent pancreatic exocrine function test 1-6 d after surgical preparation with external pancreatic fistula. We induced acute pancreatitis in another WBN/Kob rats by i.v. administration of cerulein at a rate of 10 micrograms/kg/h for 4 h 4 d after surgical preparation. Pancreatic exocrine function test was undertaken in a conscious state 1 d before and after cerulein administration.. In WBN/Kob rats not given cerulein, pancreatic exocrine function remained almost constant at 3-6 d after surgery. Marked hyperamylasemia developed immediately after cerulein administration. After its administration, the pancreas microscopically showed prominent interstitial edema and intracellular vacuolization of acinar cells in addition to the finding of pre-existing chronic pancreatitis. Basal and cholecystokinin-stimulated flow rate, bicarbonate output, and protein output, which were substantially impaired 1 d before cerulein administration, were further reduced 1 d after its administration.

Topics: Acute Disease; Amylases; Animals; Ceruletide; Chronic Disease; Disease Models, Animal; Dose-Response Relationship, Drug; Male; Pancreas; Pancreatic Function Tests; Pancreatic Juice; Pancreatitis; Rats; Rats, Inbred Strains; Sincalide

Expressions of the CCK-A and B receptor genes in fetal and adult pancreas of OLETF rats were examined by the reverse transcriptase polymerase chain reaction followed by Southern blot hybridization. The pancreatic responses to various stimulants were examined in vitro and results were compared with those of control (LETO) rats. CCK-A receptor mRNA was not expressed in the fetal pancreas of either strain or in the adult pancreas of OLETF rats, but was expressed in the adult pancreas of LETO rats. CCK-B receptor mRNA was expressed in fetal and adult pancreas in both strains. Southern blot hybridization indicated a difference in gene structure in the two strains. The maximal effective concentrations of neuromedin C, carbachol, and secretin for amylase secretion and intracellular Ca2+ movement stimulated by carbachol and neuromedin C were similar in the two strains. CCK-8 and the non-sulfated form stimulated amylase secretion only in LETO rats. These results suggest that OLETF rats are a new model of a congenital defect of the CCK-A receptor gene and should be useful for determining CCK receptor function.

Topics: Amylases; Animals; Base Sequence; Blotting, Southern; Bombesin; Brain; Calcium; Carbachol; Disease Models, Animal; DNA Primers; Female; Fetus; Gene Expression; Male; Metabolism, Inborn Errors; Molecular Sequence Data; Pancreas; Peptide Fragments; Polymerase Chain Reaction; Pregnancy; Rats; Rats, Inbred Strains; Receptor, Cholecystokinin A; Receptor, Cholecystokinin B; Receptors, Cholecystokinin; Reference Values; Secretin; Sincalide; Species Specificity

Biliary manometry, the "gold standard" for the diagnosis of sphincter of Oddi dysfunction, is associated with technical and methodological problems. The lack of a suitable experimental model has hindered efforts to solve these problems. We report here on the first practical animal model for endoscopic biliary manometry, similar in technique to the procedure in humans. Piglets were sedated and intubated with a standard human duodenoscope. A standard water-perfused manometry catheter was inserted into the bile duct. The biliary sphincter was identified by a zone of high-pressure activity with superimposed phasic contractions. The sphincter responded normally to the administration of cholecystokinin and morphine by relaxation and contraction, respectively. This model should be useful for training in biliary manometry, and facilitate technical innovations in the field. Since it is relatively atraumatic, it may also be better than existing surgical models for studying the normal physiology and pharmacology of the sphincter of Oddi.

Topics: Animals; Catheterization; Common Bile Duct Diseases; Disease Models, Animal; Duodenoscopy; Gastroenterology; Injections, Intravenous; Male; Manometry; Morphine; Research; Sincalide; Sphincter of Oddi; Swine

The present work studies the effect of previous hydrocortisone administration (10 mg/kg/day) over 7 days on the later development of diet-induced acute pancreatitis in the rat. Acute pancreatitis was induced by feeding a diet deficient in choline and supplemented with 0.5% ethionine (CDE diet) over 10 days. Hydrocortisone pretreatment exacerbated CDE-induced acute pancreatitis. There was a significant increase in serum amylase, pancreatic edema, and haematocrit levels and an insignificant decrease in pancreatic mass in rats pretreated with hydrocortisone. Pancreatic enzyme secretion was strongly reduced in the rats subjected to acute pancreatitis, and although the drop in enzyme levels did not reach statistical significance, the values of secretion were even further reduced in the animals treated with hydrocortisone, pointing to the absence of pancreatic functionality. This effect can be attributed to enzyme storage elicited by previous hydrocortisone administration; activated intracellularly, these enzymes could aggravate the pathology. Administration of the cholecystokinin octapeptide (CCK-8) (10 micrograms/kg/day) during the development of acute pancreatitis in animals pretreated with hydrocortisone substantially improved the general state of the animals' pancreases. There was a significant decrease in serum amylase, pancreatic edema and haematocrit levels in rats injected with CCK, which was accompanied by an increase in pancreatic functionality. Conversely, the administration of L-364,718 (0.1 mg/kg/day), a CCK antagonist, did not improve pancreatic functionality and did not appreciably affect the general state of the organ. It is concluded that in rats with storage levels increased by hydrocortisone administration that are subjected to acute pancreatitis, the secretagogue effect of CCK is more beneficial than the repose of the gland induced by L-364,718.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Amylases; Analysis of Variance; Animals; Antimetabolites; Benzodiazepinones; Choline; Devazepide; Disease Models, Animal; Ethionine; Hydrocortisone; Male; Organ Size; Pancreas; Pancreatitis; Rats; Rats, Wistar; Sincalide

The present study determined the effect of pretreatment with "silent" selective 5-HT1A receptor antagonists on cholecystokinin (CCK)-mediated effects on rat behaviour in the elevated x-maze model of anxiety. In the absence of 5-HT1A receptor antagonists, non-sulphated cholecystokinin-octapeptide (CCK-8ns; 10 and 50 micrograms/kg, i.p.; 30 min prior to testing) produced an anxiogenic profile of behaviour on the x-maze, reducing the number of open arm entries and the number of exploratory head dips, while increasing the level of risk-assessment as measured by the number of stretched-attend postures. CCK-8ns did not, however, alter ambulatory activity. Two 5-HT1A receptor antagonists were employed in these experiments: (+)WAY100135 (the active enantiomer of N-tert-butyl-3-(4-(2-methoxyphenyl)piperzin-1-yl)- 2-phenylpropronamine) [sequence: see text] and WAY100635 (N-[2-[4(2-methoxyphenyl)-1-piperazinyl-1-piperazinyl]-N-2- pyridinyl)cyclohexanecarbonate [sequence: see text] trihydrochloride). When administered 10 min prior to CCK-8ns, (+) WAY100135 and 0.3 mg/kg s.c.) significantly attenuated profile of CCK-8ns. (+)WAY100135 was also demonstrated to significantly inhibit postsynaptic 5-HT1A receptor-mediated 8-OH-DPAT (8-hydroxy-2-(di-N-propylamino)tetralin)-induced 5-HT syndrome at the same dose used in the x-maze experiment. Neither (+)WAY100135 nor WAY100635 had any affects on ambulatory activity. These results support a CCK/5-HT1A receptor interaction in the modulation of aversion in rats exposed to the elevated x-maze.

Topics: 8-Hydroxy-2-(di-n-propylamino)tetralin; Animals; Anxiety; Behavior, Animal; Cholecystokinin; Disease Models, Animal; Dose-Response Relationship, Drug; Male; Maze Learning; Peptide Fragments; Piperazines; Pyridines; Rats; Rats, Inbred Strains; Serotonin Antagonists; Sincalide; Time Factors

The aim of this work was to study in rats the temporal course of laboratory parameters and morphologic features in acute pancreatitis induced by cholecystokinin octapeptide (CCK-8) or by a closed duodenal loop. Pancreatitis was induced either with an overdose of CCK-8 (3 x 75 micrograms/kg at 1 h intervals) or by ligation of the duodenum on both sides of the bilio-pancreatic duct. The animals were examined at 0, 2, 4, 8, 16 and 24 h after AP induction. In CCK-8-induced acute pancreatitis, the pancreatic weight/body weight ratio (8.2 +/- 1.1 mg/g) and the amylase level (44.8 +/- 7.5 x 10(3) U/ml) were significantly increased vs. the controls (4.5 +/- 0.8 mg/g and 3.3 +/- 0.2 x 10(3) U/ml, respectively) 2 h after the intervention. The plasma CCK was significantly increased at 4 h (4.55 +/- 1.7 pM) and remained elevated thereafter. The tissue malonyldialdehyde concentration was significantly elevated at 8 h (0.28 +/- 0.07 mumol/mg pancreas) vs. the controls (0.20 +/- 0.02 mumol/mg pancreas). In closed duodenal loop-induced acute pancreatitis, the ratio pancreatic weight/body weight steadily increased during the study; it reached its maximum level at 24 h (7.1 +/- 0.5 mg/g) vs. the sham-operated control (4.8 +/- 0.9 mg/g). The serum amylase level was significantly elevated at 2 h (47.1 +/- 9.3 x 10(3) U/ml), and then decreased steadily. Plasma CCK values were significantly higher than the controls throughout the study. A significant increase in the tissue malonyldialdehyde concentration (0.94 +/- 0.15 mumol/mg vs. 0.20 +/- 0.01 mumol/mg pancreas) appeared at 4 h. Our data indicate that in CCK-8-induced acute pancreatitis the laboratory signs of pancreatitis are most expressed at 4 h, whereas the morphologic changes culminate 8 h, following the last CCK injection. In closed duodenal loop-induced acute pancreatitis, the histologic findings showed a progressive deterioration. Endogenous CCK and oxygen-derived free radicals seem to play a role in the pathogenesis of both types of acute pancreatitis.

Topics: Acute Disease; Amylases; Animals; Cholecystokinin; Disease Models, Animal; Duodenal Obstruction; Lipid Peroxidation; Male; Malondialdehyde; Organ Size; Pancreatitis; Rats; Rats, Wistar; Sincalide; Time Factors

The neuroprotective actions of cholecystokinin (CCK) peptides were investigated in a mouse hypoxia model, in which the animals were successively exposed to CO gas. Working memory impairment 5 days after CO exposure was examined by using a Y-maze test; delayed amnesia was examined 7 days after CO exposure, by using a step-down type passive avoidance test. Ceruletide (1-100 micrograms/kg, given s.c. 30 min before CO exposure) significantly prevented the CO-induced impairment of performance in both tests, the improvement being correlated with the severity of hypoxia. This severity was increased by maintaining the body temperature at 38 degrees C. Ceruletide was less effective when injected immediately after a single CO exposure. The order of potency of the CCK-peptides administered systemically was: ceruletide > CCK-8S > CCK-8NS >> CCK-4. Ceruletide (0.03-0.3 micrograms/mouse) and CCK-8S (0.03-1 microgram/mouse) prevented CO-induced amnesia after i.c.v. administration. Under all experimental conditions, dizocilpine [MK-801, (+)-5-methyl-10,11-dihydro-5H-dibenzo(a,d)cyclohepten-5,10-imine maleate, 500 micrograms/kg s.c. or 10 micrograms/mouse i.c.v.] prevented completely the CO-induced amnesia. The protective effects of systemic ceruletide were blocked, partially but significantly, by the preadministration of L-364,718 (3S-(-)-N-[2,3-dihydro-1-methyl-2-oxo-S-phenyl-1H-1,4- benzodiazepine-3-yl]-1H-indole-2-carboxamide, 1-10 mg/kg i.p.), a selective CCK-A receptor antagonist. L-365,260 ([3R-(+)-2,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepine-3-yl] -N' - [3-methyl-phenyl]urea), a CCK-B antagonist, also decreased ceruletide-induced protection.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Amnesia; Animals; Avoidance Learning; Carbon Monoxide; Ceruletide; Disease Models, Animal; Injections, Intraventricular; Male; Mice; Sincalide

The effect of CCK-8 (50 ng, i.c.v.) on the neurohypophysial vasopressin and oxytocin storage was estimated in haemorrhaged (1 ml per 100 g b.w.) male Wistar rats. In another experimental series rats dehydrated for three days were given CCK-8 in a daily i.c.v. dose of 50 ng. The neurohypophysial vasopressin and oxytocin content was bioassayed by pressor effect following Dekański or milk-ejection activity in vitro following van Dongen and Hays, respectively. The decrease of neurohypophysial vasopressin and oxytocin content, brought about by dehydration, was significantly less marked in animals treated with CCK-8. The depletion of neurohypophysial vasopressin and oxytocin content in haemorrhaged animals could be completely inhibited by earlier i.c.v. administration of CCK-8. It is suggested that hypothalamic cholecystokinin may serve as a modulator of neurohypophysial function.

Topics: Animals; Bloodletting; Dehydration; Disease Models, Animal; Hemorrhage; Injections, Intraventricular; Male; Models, Biological; Oxytocin; Pituitary Gland, Posterior; Rats; Rats, Wistar; Sincalide; Vasopressins

Alzheimer's Disease (AD) patients have a severe degeneration of cholinergic neurons in their cerebral cortices. Basal forebrain (BF)-lesioned rat is used as a model animal of a cholinergic deficit in the cerebral cortex. Cholinergic markers were decreased in the cerebral cortex of BF-lesioned rats. Intracerebroventricular continuous infusion of cholecystokinin octapeptide (CCK8) following BF lesion obviously preserved these cholinergic markers. These results suggest that CCK8 prevents the degeneration of cholinergic neurons in the cerebral cortex following BF lesion.

Topics: Acetylcholine; Alzheimer Disease; Animals; Cerebral Cortex; Choline; Choline O-Acetyltransferase; Cholinergic Fibers; Disease Models, Animal; Injections, Intraventricular; Male; Prosencephalon; Rats; Rats, Inbred Strains; Sincalide

Systemic administration of CCK-8S (1 or 10 micrograms/kg IP) markedly inhibited L-dopa-induced dyskinesias in parkinsonian monkeys, but did not interfere with locomotor stimulation by L-dopa. CCK analogues may be useful antidyskinetic agents for improved control of Parkinson's disease.

Topics: 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; Animals; Disease Models, Animal; Dyskinesia, Drug-Induced; Levodopa; Parkinson Disease, Secondary; Saimiri; Sincalide

The chronically reserpine-treated rat, an experimental model for cystic fibrosis, exhibits generalized exocrinopathy, impaired pancreatic secretion, and decreased pancreatic amylase. Although chronic reserpine treatment induces malnutrition by decreasing food consumption and growth, the effects of this malnutrition per se on the exocrine pancreas have not been considered. In this study, the effects of chronic reserpine treatment and malnutrition on the exocrine pancreas were determined using pair-fed controls. Male, Sprague-Dawley rats were treated daily subcutaneously for 5 to 7 days with: no injection (control), 1.0 ml/kg vehicle or sham (control-sham, pair fed-sham), or 0.5 mg/kg reserpine (chronically reserpine-treated). Both chronic reserpine-treatment and pair-feeding significantly decreased food consumption (40%), body weight (51 and 59%), total pancreatic amylase (49 and 56%) and specific amylase activity (62 and 61%), pancreatic protein (65 and 75%), and pancreatic weights (62 and 65%) compared to controls. These decreases, however, were comparable between the chronically reserpine-treated and pair fed-sham rats. In contrast, the secretory response to the biologically active cholecystokinin analog cholecystokinin octapeptide was significantly attenuated in isolated pancreatic acini prepared from reserpine-treated rats compared to that from either control or pair-fed sham rats. Malnutrition decreased pancreatic amylase activity and protein comparably to reserpine treatment, but only partially attenuated the secretory response to cholecystokinin octapeptide. Based on the results of this study, pair-fed controls should be used to distinguish between the effects of reserpine alone and the induced malnutrition on pancreatic exocrine function in studies of this experimental model of cystic fibrosis.

Topics: Amylases; Animals; Body Weight; Cystic Fibrosis; Disease Models, Animal; Eating; Lipase; Male; Nutrition Disorders; Organ Size; Pancreas; Rats; Rats, Inbred Strains; Reserpine; Sincalide