glycodeoxycholic-acid and Disease-Models--Animal

Biliary atresia (BA) is a severe inflammatory and fibrosing neonatal cholangiopathy disease characterized by progressive obstruction of extrahepatic bile ducts, resulting in cholestasis and progressive hepatic failure. Cholestasis may play an important role in the inflammatory and fibrotic pathological processes, but its specific mechanism is still unclear. Necroptosis mediated by Z-DNA-binding protein 1 (ZBP1)/phosphorylated-mixed lineage kinase domain-like pseudokinase (p-MLKL) is a prominent pathogenic factor in inflammatory and fibrotic diseases, but its function in BA remains unclear. Here, we aim to determine the effect of macrophage necroptosis in the BA pathology, and to explore the specific molecular mechanism. We found that necroptosis existed in BA livers, which was occurred in liver macrophages. Furthermore, this process was mediated by ZBP1/p-MLKL, and the upregulated expression of ZBP1 in BA livers was correlated with liver fibrosis and prognosis. Similarly, in the bile duct ligation (BDL) induced mouse cholestatic liver injury model, macrophage necroptosis mediated by ZBP1/p-MLKL was also observed. In vitro, conjugated bile acid-glycodeoxycholate (GDCA) upregulated ZBP1 expression in mouse bone marrow-derived monocyte/macrophages (BMDMs) through sphingosine 1-phosphate receptor 2 (S1PR2), and the induction of ZBP1 was a prerequisite for the enhanced necroptosis. Finally, after selectively knocking down of macrophage S1pr2 in vivo, ZBP1/p-MLKL-mediated necroptosis was decreased, and further collagen deposition was markedly attenuated in BDL mice. Furthermore, macrophage Zbp1 or Mlkl specific knockdown also alleviated BDL-induced liver injury/fibrosis. In conclusion, GDCA/S1PR2/ZBP1/p-MLKL mediated macrophage necroptosis plays vital role in the pathogenesis of BA liver fibrosis, and targeting this process may represent a potential therapeutic strategy for BA.

Topics: Animals; Biliary Atresia; Cholestasis; Disease Models, Animal; Glycodeoxycholic Acid; Liver Cirrhosis; Macrophages; Mice; Necroptosis; Protein Kinases; RNA-Binding Proteins; Sphingosine-1-Phosphate Receptors

Acute lung injury (ALI) is one of the most common extra-pancreatic complications of acute pancreatitis. In this study, we examined the protective effect of protease inhibitor aprotinin and a matrix metalloproteinase inhibitor (MMPi) on pulmonary inflammation in rats with severe pancreatitis-associated ALI.. A rat model of acute pancreatitis (AP) was established by injecting sodium glycodeoxycholate (GDOC) into the pancreatic duct. Pharmacological interventions included pretreatment with a protease inhibitor aprotinin (10mg/kg) and a matrix metalloproteinase inhibitor (MMPi, 100g/kg). The extent of pancreatic and lung injury and systemic inflammation was assessed by examinations of blood, bronchoalveolar lavage (BAL), and lung tissue. Pancreatic or lung tissue edema was evaluated by tissue water content. Pulmonary arterial pressure and alveolar-capillary membrane permeability were evaluated post-injury via a catheter inserted into the pulmonary artery in an isolated, perfused lung model.. Pre-treatment with aprotinin or MMPi significantly decreased amylase and lactate dehydrogenase (LDH), and the wet/dry weight ratio of the lung and pancreas in AP rats. Compared to the GDOC alone group, administration of aprotinin or MMPi prevented pancreatitis-induced IL-6 increases in the lung. Similarly, treatment with aprotinin or MMPi significantly decreased the accumulation of white blood cells, oxygen radicals, nitrite/nitrates in both blood and BAL, and markedly reduced lung permeability.. Pretreatment with either aprotinin or MMPi attenuated the systemic inflammation and reduced the severity of lung and pancreas injuries. In short, our study demonstrated that inhibition of protease may be therapeutic to pulmonary inflammation in this GDOC-induced AP model.

Topics: Acute Lung Injury; Animals; Aprotinin; Cells, Cultured; Disease Models, Animal; Drug Therapy, Combination; Edema; Glycodeoxycholic Acid; Humans; Inflammation; Lung; Male; Matrix Metalloproteinase Inhibitors; Organ Culture Techniques; Pancreatitis; Pulmonary Artery; Rats; Rats, Sprague-Dawley

The effects of the glutamine on the acute pancreatitis are controversial in the clinical and experimental studies. The aim of this study was to investigate the influence of glutamine alone on acute necrotizing pancreatitis (ANP) induced by glycodeoxycholic acid in rats.. Fifty-two male Sprague-Dawley rats weighing 300-350 g were used. Rats were divided into four groups as sham + saline, sham + glutamine, ANP + saline and ANP + glutamine. ANP in rats was induced by glycodeoxycholic acid. The extent of acinar cell injury, mortality, systemic cardiorespiratory variables, functional capillary density, renal/hepatic functions, and changes in some enzyme markers for pancreatic and lung tissue were investigated during ANP in rats.. The induction of ANP resulted in a significant increase in the mortality rate, pancreatic necrosis, and serum activity of amylase, alanine aminotransferase, interleukin-6, lactate dehydrogenase in bronchoalveolar lavage fluid, serum concentration of urea, and tissue activity of myeloperoxidase and malondialdehyde in the pancreas and lung, and a significant decrease in concentrations of calcium, blood pressure, urine output, pO2, and functional capillary density. The use of glutamine alone improved these changes.. Glutamine demonstrated beneficial effect on the course of ANP in rats. Therefore, it may be used by itself in the treatment of acute pancreatitis.

Topics: Alanine Transaminase; Amylases; Animals; Detergents; Disease Models, Animal; Glutamine; Glycodeoxycholic Acid; Interleukin-6; L-Lactate Dehydrogenase; Male; Microcirculation; Pancreas; Pancreatitis, Acute Necrotizing; Rats, Sprague-Dawley; Sodium Chloride; Treatment Outcome

The endogenous immune response is influenced by the stimulation of the vagal nerve. Stimulation or ablation has a direct impact on the release of pro- and anti-inflammatory mediators. In the progression of acute pancreatitis from local to systemic disease, these mediators play a pivotal role. This study evaluates the effect of pharmacologic stimulation of the cholinergic system on pancreatic damage in experimental necrotizing pancreatitis.. Experimental severe necrotizing pancreatitis was induced in male Wistar rats using the glycodeoxycholic acid model. Animals with acute pancreatitis (n = 6) were compared with animals with acute pancreatitis and prophylactic or therapeutic pharmacologic activation of the cholinergic system using nicotine, physostigmine, or neostigmine (n = 36). Twelve hours after the induction of acute pancreatitis, morphological damage as well as the myeloperoxidase levels of the pancreas and the serum levels of high-mobility group box 1 protein were evaluated.. Prophylactic and delayed therapeutic application of nicotine, physostigmine, or neostigmine significantly attenuated the severity of acute pancreatitis 12 hours after the induction of severe necrotizing pancreatitis compared with untreated controls as evaluated with histological scores, myeloperoxidase, and high-mobility group box 1 levels (P < 0.05).. Stimulation of the cholinergic system is useful to attenuate damage in experimental acute pancreatitis. Not only prophylactic but also delayed application was effective in the present study.

Topics: Animals; Cholinergic Agents; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Glycodeoxycholic Acid; HMGB1 Protein; Humans; Male; Neostigmine; Nicotine; Pancreas; Pancreatitis, Acute Necrotizing; Peroxidase; Physostigmine; Rats; Rats, Wistar

This study aims to investigate the influence of clotrimazol (CLTZ) on acute necrotizing pancreatitis (ANP) induced by glycodeoxycholic acid in rats. Rats were divided into five groups as sham + saline, sham + CLTZ, sham + polyethylene glycol, ANP + saline, and ANP + CLTZ. ANP in rats was induced by glycodeoxycholic acid. The extent of acinar cell injury, mortality, systemic cardiorespiratory variables, functional capillary density (FCD), renal/hepatic functions, and changes in some enzyme markers for pancreatic and lung tissue were investigated during ANP in rats. The use of CLTZ after the induction of ANP resulted in a significant decrease in the mortality rate, pancreatic necrosis, and serum activity of amylase, alanine aminotransferase, interleukin-6, lactate dehydrogenase in bronchoalveolar lavage fluid, serum concentration of urea, and tissue activity of myeloperoxidase, and malondialdehyde in the pancreas and lung and a significant increase in concentrations of calcium, blood pressure, urine output, pO2, and FCD. This study showed that CLTZ demonstrated beneficial effect on the course of ANP in rats. Therefore, it may be used in the treatment of acute pancreatitis.

Topics: 14-alpha Demethylase Inhibitors; Alanine Transaminase; Amylases; Animals; Blood Pressure; Bronchoalveolar Lavage Fluid; Calcium; Clotrimazole; Disease Models, Animal; Glycodeoxycholic Acid; Interleukin-6; L-Lactate Dehydrogenase; Lung; Male; Malondialdehyde; Pancreas; Pancreatitis, Acute Necrotizing; Peroxidase; Rats; Rats, Sprague-Dawley; Urea

Platelet-activating factor (PAF) is an important mediator of inflammation and postulated to be involved in the pathogenesis of acute pancreatitis. In this study, we evaluated the therapeutic effect of PAF antagonist WEB 2086 in acute experimental pancreatitis of graded severity in rats.. According to a block design, 64 animals were randomly allocated to 8 groups. Severe necrotizing pancreatitis was induced by intraductal infusion of taurocholic acid (4%, 0.4 mL), and the combination of glycodeoxycholic acid (10 mmol/L, 1.0 mL/kg, intraductal infusion) and cerulein (5 microg/kg per hour, intravenous) was applied to induce intermediate pancreatitis, or cerulein alone (5 microg/kg per hour, intravenous) to establish edematous pancreatitis. WEB 2086 was given 15 minutes after beginning the induction of pancreatitis. Pancreatic microcirculation was analyzed in vivo with an epiluminescent microscope. Histopathology was evaluated by a validated score. Trypsinogen-activating peptide and serum amylase were analyzed sequentially.. WEB 2086 had no significant influence on the breakdown of microcirculation, leukocyte adherence, histopathological damage, and amylase levels in severe necrotizing pancreatitis, intermediate pancreatitis, and edematous pancreatitis. Only in intermediate pancreatitis was there a significant reduction of trypsinogen-activating peptide levels.. In our study, PAF antagonist WEB 2086 had no beneficial effect on microcirculation in acute experimental pancreatitis.

Topics: Amylases; Animals; Azepines; Capillaries; Cell Adhesion; Ceruletide; Disease Models, Animal; Edema; Female; Glycodeoxycholic Acid; Leukocytes; Microcirculation; Oligopeptides; Pancreas; Pancreatitis; Pancreatitis, Acute Necrotizing; Platelet Activating Factor; Platelet Aggregation Inhibitors; Rats; Rats, Wistar; Regional Blood Flow; Severity of Illness Index; Taurocholic Acid; Time Factors; Triazoles

This study investigated the effect of caffeic acid phenethyl ester (CAPE) on acute necrotizing pancreatitis (ANP) induced by glycodeoxycholic acid in rats. CAPE, an active component of honeybee propolis, has previously been determined to have antioxidant, anti-inflammatory, antiviral, and anticancer activities.. Forty-eight rats were divided into four groups of 12. Group 1 animals received intraductal saline and intravenous saline infusion treatment. Group 2 was given intraductal saline and intraperitoneal CAPE infusion treatment. ANP was induced in the animals in group 3 (ANP with saline infusion), and group 4 had induced ANP plus CAPE infusion treatment (ANP with CAPE infusion). Sampling was performed 48 h after treatment.. ANP induction significantly increased mortality rate, pancreatic necrosis, and bacterial infection in pancreatic and extrapancreatic organs. ANP also increased levels of amylase and alanine aminotransferase (ALT) in serum, increased levels of urea and lactate dehydrogenase in bronchoalveolar lavage fluid (BAL LDH), increased the activities of myeloperoxidase (MPO) and malondialdehyde (MDA) in pancreas and lung tissue, and decreased the serum calcium levels. The use of CAPE did not significantly reduce the mortality rate but significantly reduced the ALT and BAL LDH levels, the activities of MPO and MDA in the pancreas, the activity of MDA in the lungs, and pancreatic damage. The administration of CAPE did not reduce the bacterial infection.. These results indicate that CAPE had beneficial effects on the course of ANP in rats and suggest that CAPE shows promise as a treatment for ANP.

Topics: Alanine Transaminase; Animals; Antioxidants; Bacterial Translocation; Bronchoalveolar Lavage Fluid; Caffeic Acids; Detergents; Disease Models, Animal; Glycodeoxycholic Acid; L-Lactate Dehydrogenase; Lung; Male; Malondialdehyde; Pancreas; Pancreatitis, Acute Necrotizing; Peroxidase; Phenylethyl Alcohol; Rats; Rats, Sprague-Dawley

The aim of this study was to investigate the influence of enalaprilat on acute necrotizing pancreatitis (ANP) induced by glycodeoxycholic acid in rats. The induction of ANP resulted in a significant increase in the mortality rate, pancreatic necrosis, serum activity of amylase, alanine aminotransferase (ALT), and interleukin-6 (IL-6), lactate dehydrogenase (LDH) in bronchoalveolar lavage (BAL) fluid, serum concentration of urea, and tissue activity of myeloperoxidase (MPO) and maondialdehyde (MDA) in the pancreas and lung, and a significant decrease in concentrations of calcium, blood pressure, urine output and p0(2). The use of enalaprilat inhibited the changes in urine output, blood pressure, serum concentration of urea, p0(2), and tissue activity of MPO and MDA in the pancreas and lungs. It reduced the mortality and pancreatic damage. Enalaprilat demonstrated a beneficial effect on the course of ANP in rats; therefore, it may be used in the treatment of acute pancreatitis.

Topics: Alanine Transaminase; Amylases; Angiotensin-Converting Enzyme Inhibitors; Animals; Blood Pressure; Bronchoalveolar Lavage Fluid; Calcium; Ceruletide; Disease Models, Animal; Enalaprilat; Glycodeoxycholic Acid; Interleukin-6; L-Lactate Dehydrogenase; Lung; Male; Malondialdehyde; Oxygen; Pancreas; Pancreatitis, Acute Necrotizing; Partial Pressure; Peroxidase; Rats; Rats, Sprague-Dawley; Urea; Urination

Pancreatitis is a mild and self-limiting disease. Although severe forms such as acute necrotizing pancreatitis (ANP) are rare it is associated with significant mortality rate reported to be 30-70%. Probiotics are viable microbial dietary supplements when introduced in sufficient quantities can have beneficial effects. The physiological effects of probiotics include suppression of bacterial infections, production of some digestive enzymes and vitamins and reconstruction of normal intestinal microflora. In the present study, the aim was to investigate the role of probiotics on the DNA damage in the peripheral lymphocytes, in the exfoliated epithelial cells and lymphocytes of the peritoneal fluids and in the pancreatic acinar cells of ANP induced rats. DNA damage was determined by COMET assay. ANP was induced by intravenous infusion of cerulein and superimposed infusion glycodeoxycholic acid into biliopancreatic duct. Saccharomyces Boulardii was used as the probiotic agent. DNA damage in pancreatic acinar cells and exfoliated epithelial cells and the lymphocytes of the peritoneal fluids was significantly higher in pancreatitis group compared to the controls and probiotic treated groups (P<0.001). No significant difference was observed in the DNA damage between the groups in the peripheral lymphocytes. In conclusion; our results support that probiotic agent Saccharomyces Boulardii can diminish bacterial infections and offer health benefits in the therapy of pancreatitis.

Topics: Animals; Ascitic Fluid; Ceruletide; Comet Assay; Disease Models, Animal; DNA Damage; Female; Glycodeoxycholic Acid; Lymphocytes; Pancreas; Pancreatitis, Acute Necrotizing; Probiotics; Rats; Rats, Wistar; Saccharomyces

Octreotide is considered to reduce exocrine pancreatic secretion in acute hemorrhagic necrotizing pancreatitis decreasing pancreatic autodigestion. The aim of this study was to determine whether octreotide also has antioxidative effects in acute pancreatitis. Additionally time and dose of application were of interest.. Ninety male Sprague-Dawley rats were randomized into six groups (n = 15). Group 1 underwent a laparotomy, and animals in groups 2-6 received intraductal glycodeoxycholic acid followed by intravenous cerulein. Groups 3 and 4 were injected with 0.5 mg octreotide, while groups 5 and 6 received continuous intravenous infusion of 0.05 mg octreotide/h for 10 h. Treatment was initiated 6 hours after induction of pancreatitis (IP) in groups 3 and 5, and 14 h after IP in groups 4 and 6. At 24 h after IP all animals were killed and each pancreas was analyzed histopathologically. In addition, levels of pancreatic lipid peroxidation protective enzymes glutathione-peroxidase (GSH-Px) and superoxide dismutase (SOD) as well as lipid peroxidation via thiobarbituric acid reactive substances (TBARS) were determined.. Early bolus application of octreotide reduced severity of histopathological changes in acute pancreatitis and decreased lipid peroxidation in pancreatic tissue samples; however, late bolus application and continuous intravenous infusion did not influence pancreatitis or lipid peroxidation.. Octreotide seems to have a dose- and time-dependent effect on histopathology and lipid peroxidation in a model of pancreatitis in rats.

Topics: Animals; Antioxidants; Ceruletide; Disease Models, Animal; Dose-Response Relationship, Drug; Glutathione Peroxidase; Glycodeoxycholic Acid; Hemorrhage; Infusions, Intravenous; Injections, Intravenous; Lipid Peroxidation; Male; Octreotide; Pancreas; Pancreatitis, Acute Necrotizing; Rats; Rats, Sprague-Dawley; Superoxide Dismutase; Thiobarbituric Acid Reactive Substances; Time Factors

During severe acute pancreatitis (AP), the liver may show an exaggerated response to the inflammatory products of gut injury transported in the portal vein. Our aim was to explore liver proinflammatory mediator production after a 'second hit' of portal lipopolysaccharide (LPS) during AP.. Twenty-four rats underwent one of three 'first-hit' scenarios: (1) severe AP induced by intraductal glycodeoxycholic acid injection and intravenous caerulein infusion, (2) sham laparotomy, or (3) no first intervention. Eighteen hours later, all animals received a 'second hit' of portal LPS in an isolated liver perfusion system. Tumour necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta, and IL-6 concentrations were measured in portal and systemic serum, and in the perfusate 30 and 90 min after the 'second hit'. Neutrophil activation by the perfusate was assayed using dihydrorhodamine-123 fluorescence.. We observed a six-fold increase in IL-6 concentration across the liver during AP. All livers produced TNF-alpha after the portal LPS challenge, but this was not exaggerated by AP. No differential neutrophil activation by the perfusate was seen.. TNF-alpha, IL-1beta, IL-6 and neutrophil activator production by the isolated perfused liver, in response to a 'second hit' of portal LPS, does not appear to be enhanced during AP.

Topics: Amylases; Animals; Animals, Outbred Strains; Ceruletide; Disease Models, Animal; Glycodeoxycholic Acid; Interleukin-6; Lipopolysaccharides; Liver; Male; Neutrophil Activation; Neutrophils; Pancreas; Pancreatitis, Acute Necrotizing; Perfusion; Rats; Rats, Wistar; Respiratory Burst; Systemic Inflammatory Response Syndrome; Tumor Necrosis Factor-alpha

The investigation of the effects of the celecoxib as a cylooxygenase-2 (COX-2) inhibitor on the course of the acute necrotising pancreatitis (ANP) in rats. ANP was induced in 72 rats by standardized intraductal glycodeoxycholic acid infusion and intravenous cerulein infusion. The rats were divided into four groups (six rats in each group): Sham + saline, sham + celecoxib, ANP + saline, ANP + celecoxib. Six hours later after the ANP induction, celecoxib (10 mg/kg) or saline was given i.p. In the 12th hour, routine cardiorespiratuar, renal parameters were monitored to assess the organ function. The serum amylase, alanine amino transferase (ALT), interleukin 6 (IL-6), lactate dehydrogenase (LDH) in bronchoalveolar lavage (BAL) fluid, the serum concentration of the urea, the tissue activity of myeloperoxidase (MPO) and malondialdehyde (MDA) in pancreas and lungs were measured. The pancreas histology was examined. In the second part of the study, 48 rats were studied in four groups similar to the first part. Survival of all the rats after the induction of ANP was observed for 24 h. The induction of the pancreatitis increased the mortality from 0/12, in the sham groups to 4/12 (30%) in the acute pancreatitis with saline group, 5/12 (42%) in the acute pancreatitis with celecoxib group respectively, heart rate, the serum activities of amylase, ALT, the tissue activities of MPO, MDA in the pancreas and lung, and LDH in BAL fluid, the serum concentration of the urea and IL-6, the degree of the pancreatic damage and decreased the blood pressure, the urine production, pO(2) and the serum concentration of calcium. The use of celecoxib did not alter these changes except the serum IL-6 concentration, urine production and MPO, MDA activities in the tissue of the lungs and pancreas. Serum urea concentration and pancreatic damage in ANP + celecoxib group were insignificantly lesser than ANP + saline group. Whereas treatment with celecoxib improves lung and renal functions, the degree of pancreatic damage partially and the serum IL-6 level completely, it does not improve the cardiovascular and liver functions, the mortality rate and the calcium level. Celecoxib may be useful for the support of some organ functions during ANP in rats.

Topics: Animals; Celecoxib; Ceruletide; Cyclooxygenase Inhibitors; Disease Models, Animal; Edema; Glycodeoxycholic Acid; Inflammation; Interleukin-6; Lung; Male; Malondialdehyde; Multiple Organ Failure; Pancreas; Pancreatitis, Acute Necrotizing; Peroxidase; Pyrazoles; Rats; Rats, Sprague-Dawley; Sulfonamides; Survival Analysis; Urea; Urine

Steroid metabolism along the gastrointestinal tract of the cannulated pig was studied. Thi was achieved by fitting simple gut cannulas in the terminal ileum, caecum and mid-colon of three Landrace x large white boars, which enabled convenient collection of digesta and faecal samples at defined time points. Biochemical analyses showed that the neutral steroid profile of the pig is similar to that of man, dominated by cholesterol and its bacterial metabolite coprostanol. In contrast, pigs consuming a normal diet excrete appreciably lower quantities of neutral sterols in faeces. The major primary bile acids detected were the glycine and taurine amidates of hyocholic and chenodeoxycholic acids, which were rapidly converted to the free bile acids and subsequently dehydroxylated to hyodeoxycholic and lithocholic acids respectively, in the terminal ileum and caecum. Bacterial deconjugation and 7 alpha-dehyrdoxylation are virtually complete in the caecum with negligible further metabolism in the colon and faeces. On a wet weight basis the concentration of both neutral and acid steroids was shown to increase aborally. Inclusion of dietary fibre in the form of cellulose (Solka floc) and guar gum reduced steroid concentration considerably at all sites of the large intestine, which is consistent with their stool bulking effects. In conclusion, this study shows that intestinal steroid metabolism in the pig is similar to that in man despite slightly different bile acid profiles and, therefore, the multicannulated pig may serve as a useful model of man in chemoprevention studies of colorectal cancer.

Topics: Animals; Bacteria; Bile Acids and Salts; Catheterization; Cecum; Cellulose; Cholestanol; Cholesterol; Colon; Dietary Fiber; Disease Models, Animal; Feces; Galactans; Gastrointestinal Contents; Glycochenodeoxycholic Acid; Glycocholic Acid; Glycodeoxycholic Acid; Humans; Ileum; Intestinal Mucosa; Intestines; Male; Mannans; Plant Gums; Steroids; Sterols; Swine; Taurochenodeoxycholic Acid; Taurocholic Acid; Taurodeoxycholic Acid; Taurolithocholic Acid

This study was designed to investigate hyperbaric oxygen (HBO) therapy as a treatment for managing animals with induced acute pancreatitis. Forty-five anesthetized male Sprague-Dawley rats were studied. A severe acute pancreatitis model was established by combining an intravenous infusion of cerulein (15 microg/kg/h) and an intraductal injection of 0.1 ml of glycodeoxycholic acid (5 mM). Pathology, serum amylase level, pancreatic malondiadehyde levels and water content of the lungs and the pancreas were used to evaluate the severity of disease. Moreover, an in vivo microscopic technique was used to investigate microcirculatory derangement in the pancreas, i.e., flow velocity and leukocytes sticking in postcapillary venules. HBO was delivered in three regimens, i.e., 100% oxygen at 2.5 absolute atmospheric pressure (AAP), 40% oxygen at 2.5 AAP, and 100% oxygen at 1 AAP, 6 h after the initiation of induction of acute pancreatitis. All animals survived until the end of the experiments. HBO significantly improved the pathologic conditions and pancreatic malondiadehyde levels. Concomitantly, it also significantly lessened the severity of lung edema and improved the microcirculatory environment in the pancreas. Our results support the findings that HBO therapy has a beneficial effect on pancreatic microcirculation and lung edema during acute pancreatitis in rats.

Topics: 3,4-Methylenedioxyamphetamine; Acute Disease; Amylases; Animals; Ceruletide; Disease Models, Animal; Extravascular Lung Water; Glycodeoxycholic Acid; Hyperbaric Oxygenation; Lung; Male; Microcirculation; Pancreas; Pancreatitis; Pulmonary Edema; Rats; Rats, Sprague-Dawley; Water

Extraintestinal trypsinogen activation peptides (TAP) have been shown to correlate with severity of acute pancreatitis in humans as well as in various animal models. Ischemia superimposed on experimental pancreatitis, however, increases acinar cell injury without increasing TAP in plasma. We speculated that TAP generated in the pancreas might not reach the circulation in necrotizing pancreatitis due to decreased pancreatic perfusion. To test the hypothesis that generation of TAP in plasma is related to pancreatic perfusion and that plasma TAP may therefore underestimate acinar cell injury in necrotizing disease, we correlated TAP in pancreatic tissue and body fluids with capillary pancreatic blood flow in necrotizing and edematous pancreatitis. The ratio between necrosis and TAP in tissue was similar in both models; the ratio between TAP in plasma and tissue, however, was significantly lower in necrotizing pancreatitis, indicating that a certain amount of TAP generated in the pancreas did not reach the circulation. Decreased pancreatic perfusion found in necrotizing pancreatitis was consistent with this finding. Our data suggest that TAP in tissue is most reliable to indicate severity of acute pancreatitis, whereas plasma TAP may underestimate pancreatic injury in necrotizing disease due to decreased pancreatic perfusion.

Topics: Acute Disease; Animals; Ceruletide; Disease Models, Animal; Edema; Glycodeoxycholic Acid; Male; Microcirculation; Necrosis; Oligopeptides; Pancreas; Pancreatitis; Rats; Rats, Sprague-Dawley; Trypsinogen

To investigate the benefit of pentoxifylline in severe experimental pancreatitis.. Prospective, randomized, controlled study.. Experimental animal laboratory in a University hospital.. Forty-two adult male Sprague-Dawley rats.. Acute pancreatitis was induced by supramaximal stimulation with cerulein plus a pressure and volume controlled 10 min intraductal infusion of 10-mM glycodeoxycholic acid. Thirty minutes after pancreatitis was induced, animals were randomized to receive pentoxifylline (60 mg/kg over 2.5 hrs), or saline. All animals received fluid resuscitation with lactated Ringer's solution (8 mL/kg/hr), and surviving animals were killed at 24 hrs.. There was a progressively significant decrease in mean arterial pressure after pancreatitis was induced, with no difference between pentoxifylline-treated rats and controls. Hematocrit increased significantly in both groups at 6 hrs, and returned to baseline values at 24 hrs. Ascites volume and levels of trypsinogen activation peptide in plasma and ascites were similar in both groups. Twenty-four hour mortality was 47% for the pentoxifylline group and 52% for the control group. Histologic scores for necrosis, edema, inflammation, and hemorrhage showed no significant differences between the two groups.. Treatment with pentoxifylline failed to improve outcome in a model of severe acute pancreatitis in the rat.

Topics: Acute Disease; Analysis of Variance; Animals; Ceruletide; Chi-Square Distribution; Disease Models, Animal; Drug Evaluation, Preclinical; Glycodeoxycholic Acid; Male; Pancreas; Pancreatitis; Pentoxifylline; Prospective Studies; Random Allocation; Rats; Rats, Sprague-Dawley

Bacterial infection of pancreatic necrosis is thought to be a major determinant of outcome in acute necrotizing pancreatitis. The determinants and possibilities for prophylaxis are unknown and difficult to study in humans.. The time course of bacterial infection of the pancreas in a rodent model of acute necrotizing pancreatitis was characterized. The authors ascertained if there is a correlation with the degree of necrosis.. Acute pancreatitis (AP) of graded severity was induced under sterile conditions by an intravenous infusion of cerulein (5 micrograms/kg/hr) for 6 hours (mild AP), or a combination of intravenous cerulein with an intraductal infusion of 10-mM glycodeoxycholic acid (0.2 mL for 2 min for moderate AP, 0.5 mL for 10 min for severe AP). Sham-operated animals (intravenous and intraductal NaCl 0.9%) served as controls. Ninety-six hours after induction, animals were killed for quantitative bacterial examination and histologic scoring of necrosis. In addition, groups of animals with severe AP were investigated at 12, 24, 48, 96, and 144 hours.. No significant pancreatic necrosis was found in control animals (0.3 +/- 0.1) or animals with mild AP (0.6 +/- 0.1) killed at 96 hours. Necrosis scores were 1.1 +/- 0.2 for animals with moderate AP and 1.9 +/- 0.2 for animals with severe AP. Control animals did not develop significant bacterial infection of the pancreas (> or = 10(3) CFU/g). At 96 hours, the prevalence of infection was 37.5% in animals with mild AP and 50% in animals with moderate AP. In animals with severe AP, infection of the pancreas increased from 33% in the first 24 hours to 75% between 48 and 96 hours (p < 0.05). The bacterial counts and the number of different species increased with time and was maximal (> 10(11) CFU/g) at 96 hours.. Bacterial infection of the pancreas in rodent AP increases during the first several days, and its likelihood correlates with the severity of the disease. This model, which closely mimics the features of human acute pancreatitis, provides a unique opportunity to study the pathogenesis of infected necrosis and test therapeutic strategies.

Topics: Acute Disease; Animals; Bacterial Infections; Ceruletide; Colony Count, Microbial; Disease Models, Animal; Edema; Enterococcus; Escherichia coli Infections; Glycodeoxycholic Acid; Gram-Positive Bacterial Infections; Leukocytes; Male; Necrosis; Pancreas; Pancreatitis; Rats; Rats, Sprague-Dawley; Staphylococcal Infections; Survival Rate; Time Factors

Existing models of acute pancreatitis have limitations to studying novel therapy. Whereas some produce mild self-limited pancreatitis, others result in sudden necrotizing injury. The authors developed an improved model providing homogeneous moderately severe injury by superimposing secretory hyperstimulation on minimal intraductal bile acid exposure. Sprague-Dawley rats (n = 231) received low-pressure intraductal glycodeoxycholic acid (GDOC) at very low (5 or 10 mmol/L) concentrations followed by intravenous cerulein. Cerulein or GDOC alone caused only very mild inflammation. However, GDOC combined with cerulein was uniformly associated with more edema (p less than 0.0005), acinar necrosis (p less than 0.01), inflammation (p less than 0.006), and hemorrhage (p less than 0.01). Pancreatic injury was further increased and death was potentiated by increasing volume and duration of intraductal low-dose GDOC infusion. There was significant morphologic progression between 6 and 24 hours. The authors conclude that (1) combining minimal intraductal bile acid exposure with intravenous hyperstimulation produces homogeneous pancreatitis of intermediate severity that can be modulated at will; (2) the injury is progressive over at least 24 hours with finite mortality rate; (3) the model provides superior opportunity to study innovative therapy.

Topics: Acute Disease; Animals; Blood Chemical Analysis; Ceruletide; Disease Models, Animal; Glycodeoxycholic Acid; Hemodynamics; Infusions, Intravenous; Male; Pancreas; Pancreatic Ducts; Pancreatitis; Pulmonary Gas Exchange; Rats; Rats, Inbred Strains

Hypocalcemia and lipid abnormalities commonly occur in acute pancreatitis. Experimentally, increased plasma concentrations of free fatty acids (NEFA) can lower the serum calcium (Ca). We hypothesized that changes in blood-ionized calcium might parallel changes in NEFA concentration in pancreatitis. This hypothesis was tested in a model of severe necrotizing pancreatitis and a model of mild edematous pancreatitis. Adult male Sprague-Dawley rats (300-400 g) were randomized to receive: 100 microL sodium glycodeoxycholic acid (GDOC 34 mmol/L) infused into the pancreatic duct to produce severe necrotizing pancreatitis (Group 1); 100 microL 0.9% NaCl (NS) infused into the pancreatic duct (Group 2); Sham laparotomy (Group 3); A 6 h IV infusion of cerulein (5 mucg/kg/h) to produce mild edematous pancreatitis (Group 4); and a 6 h IV infusion of NS (Group 5). A significant time dependent decrease in blood-ionized Ca concentration, compared to normal rats, was observed in both GDOC-pancreatitis (0.836 +/- .057 vs 1.069 +/- .038 mmol/L p less than 0.001) and cerulein pancreatitis (0.988 +/- .028 vs 1.069 +/- .038 p less than 0.05), which was maximal 24 h after induction of pancreatitis. The degree of hypocalcemia correlated with the severity of pancreatitis (GDOC 0.836 +/- .057 vs cerulein 0.988 +/- .028 p less than .001). Hypocalcemia was not observed in any of the control groups. All experimental and control groups had significantly increased baseline NEFA concentrations compared with normal rats (p less than 0.001); however, no further increase in NEFA concentration occurred in conjunction with the observed time-dependent decline in ionized calcium concentrations. Although the NEFA concentrations observed in these experiments were comparable to those measured in human acute pancreatitis (exclusive of hyperlipemic pancreatitis), the time course of the changes suggests that increases in serum NEFA concentrations in experimental pancreatitis are not the primary factor mediating hypocalcemia.

Topics: Acute Disease; Amylases; Animals; Calcium; Ceruletide; Disease Models, Animal; Edema; Fatty Acids, Nonesterified; Glycodeoxycholic Acid; Hypocalcemia; Male; Pancreatic Ducts; Pancreatitis; Random Allocation; Rats; Rats, Inbred Strains

In a model of acute pancreatitis which requires that pancreatic enzymes leak from a permeable duct, we studied the role of intravenous enterokinase (195,000 daltons) in pancreatic enzyme activation. Anesthetized cats were given intravenous 16,16-dimethyl prostaglandin E2 to increase pancreatic blood flow and microvascular permeability. In some animals the permeability of the pancreatic duct was increased by perfusion of the duct with glycodeoxycholic acid (7.5 mM). Endogenous enzyme secretion was stimulated by IV CCK and secretin. Some cats also received enterokinase intravenously. Those animals that received PGE2, glycodeoxycholate, and enterokinase all developed pancreatitis. When any of these agents were not given the pancreases appeared normal. These findings were consistent with the hypothesis that intravenous enterokinase leaked from small pancreatic blood vessels into the pancreatic parenchyma and/or ducts where activation of pancreatic enzymes occurred. The development of pancreatitis appeared to require an increase in both microvascular and ductal permeability.

Topics: 16,16-Dimethylprostaglandin E2; Acute Disease; Animals; Capillary Permeability; Cats; Disease Models, Animal; Enteropeptidase; Glycodeoxycholic Acid; Pancreas; Pancreatic Ducts; Pancreatitis; Particle Size; Permeability

Hyodeoxycholic acid and its isomer, 6 beta-hyodeoxycholic acid, when added to a lithogenic diet prevented the formation of cholesterol gallstones and crystals in prairie dogs. This beneficial effect occurred in the presence of bile supersaturated with cholesterol. Hyodeoxycholic acid abolished the feedback inhibition of hepatic hydroxymethylglutaryl coenzyme A reductase activity, the rate-limiting enzyme of cholesterol synthesis, and prevented elevations in serum and liver cholesterol observed in animals fed a 0.4 percent cholesterol diet. The gallbladder bile of the animals fed hyodeoxycholic acid and 6 beta-hyodeoxycholic acid contained abundant liquid crystals. This suggests that these bile acids prevented the transition of cholesterol from its liquid crystalline phase to solid crystals and stones.

Topics: Animals; Bile; Cholelithiasis; Cholesterol; Cholesterol, Dietary; Crystallization; Deoxycholic Acid; Diet; Disease Models, Animal; Female; Glycodeoxycholic Acid; Hydroxymethylglutaryl CoA Reductases; Liver; Male; Microsomes, Liver; Sciuridae