Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030305 (pancreatitis)
 16,014 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Studies in animal models suggest that oxygen radicals are important in the pathogenesis of acute pancreatitis. Cerulein, a decapeptide isolated from the skin of the frog, Hyla caerula, is closely related to the C-terminus of cholecystokinin and it is a potent stimulant of pancreatic exocrine secretion. The aim of the present study was to measure the activity of endogenous scavengers, superoxide dismutase, catalase and glutathione levels in cerulein-induced acute pancreatitis in rats. We found that the plasma amylase and ribonuclease levels in the pancreatitis group were both significantly high (p < 0.01, p < 0.05, respectively) when compared with the control group. Although superoxide dismutase and glutathione levels of pancreatic tissue were decreased significantly (p < 0.01, p < 0.01 respectively), we observed a significant increase (p < 0.01) in catalase activity in the cerulein treated group compared to the control group. Therefore, we concluded that the profound alteration of the activities of endogenous scavengers (superoxide dismutase, catalase) and glutathione depletion occurring after cerulein-induced pancreatitis seemed to be important in tissue injury and may provide the basis for successful therapy of the disease.
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PMID:The endogenous scavengers in cerulein-induced acute pancreatitis. 754 30

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.
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PMID:Time-course changes in pancreatic laboratory and morphologic parameters in two different acute pancreatitis models in rats. 754 70

Cholecystokinin (CCK) receptor antagonists have been reported on have an inhibitory effect on acute experimental pancreatitis, but their long-term administration is also reported to block pancreatic regeneration. We examined whether the short-term administration of KSG-504 (KSG), a synthetic CCK-A receptor antagonist, inhibited the regeneration of pancreatic acinar cells after ethionine-induced acute pancreatitis in rats. KSG (50 mg/kg), given 12 times by subcutaneous injection at 6-h intervals, prevented the reduction of protein, amylase, and trypsinogen levels, and the DNA content of the pancreas and facilitated the recovery of these values. Ornithine decarboxylase activity in pancreatic tissue and a 5-bromo-2'-deoxyuridine labeling study indicated that DNA synthesis was accelerated in rats treated with KSG. These findings suggest that the short-term administration of KSG inhibits the development of ethionine-induced acute pancreatitis and facilitates the regeneration of acinar cells.
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PMID:Effects of short-term administration of the CCK receptor antagonist, KSG-504, on regeneration of pancreatic acinar cells in acute pancreatitis in rats. 755 Aug 60

To study the early pathogenesis of acute edematous pancreatitis in dogs, we examined the relationship of pancreatic hyperstimulation with cholecystokinin-8 (10 micrograms/kg/hr intravenously for 6 hr) to alterations in circulating pancreatic enzymes and pancreatic morphology with special reference to trypsinogen activation. Cholecystokinin-8 infusion was associated with increases in plasma amylase, lipase, trypsin-like immunoreactivity, and plasma and urine trypsinogen activation peptide. Pancreatic parenchymal swelling and interlobular and subcapsular fluid accumulations were detected ultrasonographically within 2 hr of cholecystokinin-8. Circulating trypsin-like immunoreactivity and trypsinogen activation peptide in urine reached a peak at 2 and 4 hr, respectively, then declined despite progressive increases in circulating amylase and lipase and intrapancreatic fluid. No significant changes were observed in dogs receiving a saline infusion. This study illustrates that cholecystokinin-8 induces edematous pancreatitis in dogs that is associated with a short-lived burst of trypsinogen activation.
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PMID:Cholecystokinin-8 induces edematous pancreatitis in dogs associated with short burst of trypsinogen activation. 758 82

Receptor desensitization is a key process for the protection of the cell from continuous or repeated exposure to high concentrations of an agonist. Well-established mechanisms for desensitization of guanine nucleotide-binding protein (G protein)-coupled receptors include phosphorylation, sequestration/internalization, and down-regulation. In this work, we have examined some mechanisms for desensitization of the cholecystokinin (CCK) receptor which is native to the pancreatic acinar cell, and have found the predominant mechanism to be distinct from these recognized processes. Upon fluorescent agonist occupancy of the native receptor, it becomes "insulated" from the effects of acid washing and becomes immobilized on the surface of the plasma membrane in a time- and temperature-dependent manner. This localization was assessed by ultrastructural studies using a colloidal gold conjugate of CCK, and lateral mobility of the receptor was assessed using fluorescence recovery after photobleaching. Of note, recent application of the same morphologic techniques to a CCK receptor-bearing Chinese hamster ovary cell line demonstrated prominent internalization via the clathrin-dependent endocytic pathway, as well as entry into caveolae (Roettger, B.F., R.U. Rentsch, D. Pinon, E. Holicky, E. Hadac, J.M. Larkin, and L.J. Miller, 1995, J. Cell Biol. 128: 1029-1041). These organelles are not observed to represent prominent compartments for the same receptor to traverse in the acinar cell, although fluorescent insulin is clearly internalized in these cells via receptor-mediated endocytosis. In this work, the rate of lateral mobility of the CCK receptor is observed to be similar in both cell types (1-3 x 10(-10) cm2/s), while the fate of the agonist-occupied receptor is quite distinct in each cell. This supports the unique nature of desensitization processes which occur in a cell-specific manner. A plasmalemmal site of insulation of this important receptor on the pancreatic acinar cell could be particularly effective to protect the cell from processes which might initiate pancreatitis, while providing for the rapid resensitization of this receptor to ensure appropriate pancreatic secretion to aid in nutrient assimilation for the organism.
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PMID:Insulation of a G protein-coupled receptor on the plasmalemmal surface of the pancreatic acinar cell. 762 59

In the absence of causative therapy of acute pancreatitis the management of the disease focus on treatment and prevention of complications and symptoms. In mild acute pancreatitis intravenous fluid administration, analgetics and avoidance of oral fluid or food intake is sufficient in most cases. The treatment of severe pancreatitis involves identification of pancreatic and peripancreatic necroses, best demonstrated and evaluated by contrast-enhanced computerized tomography (CT). Infection of such necroses is the most common cause of death from acute pancreatitis. Recent data suggest that antibiotic prophylaxis is worthwhile and it should therefore always be instituted in the severe form of the disease. Careful monitoring of vital functions is mandatory and early treatment with assisted ventilation and renal dialysis is advised. Adequate volume replacement and nutritional support is important. The role of the gut in the development of infected necroses is becoming increasingly obvious. Also, the absence of food in the intestine may increase the intestinal barrier damage. Therefore, enteral nutrition is discussed as a logical step in pancreatitis treatment. However, the food should be delivered below the ligament of Treitz (below the area of the cholecystokinin (CCK) cells) as CCK stimulation probably worsen the course of the disease.
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PMID:Conservative treatment in acute pancreatitis. 766 93

Involvement of endogenous cholecystokinin (CCK) in the development of acute pancreatitis induced in rats by closed duodenal loop (CDL) was examined, and the effects of the potent and specific CCK receptor antagonist loxiglumide on this model of acute pancreatitis were evaluated. Plasma CCK bioactivity was markedly elevated 3 and 6 h after onset of acute pancreatitis. A single subcutaneous injection of 50 mg/kg body wt of loxiglumide 30 min before the induction of acute pancreatitis completely eliminated the hypercholecystokinemia. Loxiglumide given 3 h after the induction of acute pancreatitis suppressed plasma CCK bioactivity, which had risen up to 30-fold over basal value (0 h) at 3 h, to nearly the basal level. Loxiglumide pretreatment, in addition, significantly prevented the rise in serum amylase and lipase activity, as well as the increase in ascitic volume. It also ameliorated histological alterations of hemorrhagic and necrotizing pancreatitis. Reduction of plasma CCK bioactivity by loxiglumide after the onset of pancreatitis slowed the rate of progression of pancreatitis. However, pancreatic wet weight and cellular infiltration were not significantly influenced by loxiglumide treatment. These observations suggest that endogenous CCK is not involved in the initiation of acute hemorrhagic and necrotizing pancreatitis induced by CDL, but is involved in the development of pancreatitis in this model.
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PMID:Involvement of endogenous cholecystokinin in the development of acute pancreatitis induced by closed duodenal loop. 767 22

Cholecystokinin and its analogues such as cerulein, muscarinic cholinergic agonists, and gastrin-releasing peptide (bombesin) bind to distinct receptors on the surface of pancreatic acinar cells and stimulate digestive protein secretion by a calcium-dependent mechanism. The mechanisms of the calcium-dependent secretagogue classes has been assumed to be similar. In this study we have noted that dispersed pancreatic acini secrete comparable maximal rates of amylase in response to cerulein and bombesin; however, the maximal level of phosphatidylinositol 4,5-bisphosphate hydrolysis was less with bombesin than with cerulein. The high agonist dose-inhibited secretion in vitro observed with cerulein was absent with bombesin. In vivo administration of supramaximal secretory stimulating doses of both cerulein and bombesin caused pancreatic edema; however, the increase in serum concentrations of amylase and lipase induced by cerulein treatment was not detected with bombesin. These data indicate that cerulein and bombesin display distinctly different effects on the exocrine pancreas both in vivo and in vitro. That pancreatic edema and elevated serum enzyme levels may be the result of different cellular mechanisms in experimental pancreatitis is strongly suggested.
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PMID:Different effects of hyperstimulation by similar classes of secretagogues on the exocrine pancreas. 767 26

The present study investigates the effect of oral pretreatment with the protease inhibitor camostate on the outcome of pancreatitis in three experimental models. In pancreatitis induced by overstimulation with cholecystokinin (CCK) in rats, pancreatic enzymes and the histological degree of pancreatitis were quantified; in pancreatitis induced by a choline-deficient ethionine-supplemented (CDE) diet in mice, the effect on survival was monitored; and in bile-induced pancreatitis in rats, the effect on survival, pancreatic enzymes, and histology was studied. Feeding of camostate (200 mg/kg/day) for 2 weeks worsened the histological degree of pancreatitis induced by overstimulation with CCK or by injection of taurocholate. The concentration of amylase in the pancreas and in serum was significantly lower after pretreatment with camostate, both in cerulein-induced pancreatitis and in bile-induced pancreatitis, while the concentration of trypsin in the pancreas was significantly increased in the camostate-treated animals. Pretreatment with camostate significantly lowered survival. In pancreatitis induced by a CDE diet, 3 of 20 mice survived the observation period, while 9 of 20 control animals survived (p < 0.05). In taurocholate-induced pancreatitis, 5 of 29 rats were alive after 3 days versus 18 of 30 animals in the control group (p < 0.001). CCK levels were not elevated in camostate-treated rats, when pancreatitis was induced 24 h after finishing camostate feeding. It is concluded that camostate induced pancreatic hypertrophy and increased concentration of proteolytic enzymes aggravate experimental panceatitis and that this is not mediated by increased CCK levels.
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PMID:Effect of camostate administration for two weeks on experimental pancreatitis in mice and rats. 767 29

Cholecystokinin (CCK) receptor antagonists are shown to have therapeutic as well as preventive effects in some types of acute pancreatitis. However, there is a possibility that administration of CCK receptor antagonists with a high inhibitory potency on the endocrine pancreas to patients with acute pancreatitis exacerbates the associated glucose intolerance. In the present study we simultaneously examined the effects of the newly developed benzodiazepine derivative FK480 and proglumide-related antagonist KSG-504 on CCK octapeptide (CCK-8)-stimulated exocrine and endocrine function in the isolated perfused rat pancreas. FK480 and KSG-504 inhibited CCK-8-stimulated pancreatic juice flow, protein output, and insulin release in a dose-dependent manner. FK480 was approximately 10 times more potent than KSG-504 in inhibiting exocrine and endocrine secretion. Both antagonists inhibited CCK-8-stimulated insulin release more potently than exocrine secretion. FK480 caused a dose-dependent residual inhibition of exocrine secretion after its removal from the perfusate, whereas insulin release was only slightly impaired even at the highest dose. In contrast, termination of KSG-504 infusion resulted in an immediate increase in both exocrine and insulin responses without causing any residual inhibition. With regard to the residual inhibition, therefore, KSG-504 had no significant influences on exocrine and insulin release, whereas FK480 inhibited exocrine secretion more potently than insulin response. These results suggest that FK480 might become a useful therapeutic agent for pancreatitis with respect to its long-duration inhibitory effect on exocrine secretion and short-duration inhibitory effect on insulin release.
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PMID:Different inhibitory effects of the newly developed CCK receptor antagonists FK480 and KSG-504 on pancreatic exocrine and endocrine secretion in the isolated perfused rat pancreas. 771 33


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