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)

Ethanol-associated fatty liver was induced in rats fed a nutritionally deficient liquid diet containing 36% of total calories as ethanol. Control rats received the same diet with sucrose substituted isocalorically for ethanol. After 40 days, hepatic lipid content of the ethanol-maintained animals was four-fold greater than controls and ultrastructural changes in hepatocytes were well established. Clearance of intravenously administered human enterokinase from the circulation as well as bile flow were, however, the same in both groups. The proportion of enterokinase appearing in catalytically active form in bile after intravenous injection was substantially greater in the ethanol-maintained animals than the isocaloric controls; the difference was highly significant (p less than 0.001) and reached two- to four-fold after 70 days on the diet. These findings would suggest that the ability of hepatocytes to degrade enterokinase cleared from the blood may be bypassed or impaired by prolonged ethanol consumption and a deficient diet. Catalytically active enterokinase in bile may participate in the development of some types of acute necrotising pancreatitis.
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PMID:Biliary excretion of enterokinase in rats: studies in alcoholic rats with fatty liver. 633 13

The osmolality of contrast injected retrograde into the rat pancreatic duct did not affect the severity of the pancreatitis (Urografin, 1,300 mOsm/kg, and Hexabrix, 580 mOsm/kg). The severity of the pancreatitis induced in rats was assessed by survival rate, histologic grading, wet lung ratio, and serum levels of amylase, lipase, and trypsin-like activity. Rats with pancreatitis induced by retrograde injected Urografin, lipopolysaccharide, taurocholic acid plus enterokinase were treated with either intravenous (i.v.) FUT-175 (Nafamstat Mesilate), FUT-175 administered by retrograde pancreatic injection, i.v. terbutaline, i.v. piperacillin sodium, piperacillin sodium by retrograde pancreatic duct injection, or a combination of FUT-175 plus terbutaline and piperacillin. Survival among the rats was increased and the incidence of pancreatic infection reduced in rats treated with i.v. piperacillin or with a combination of FUT-175 plus i.v. terbutaline, plus i.v. piperacillin compared to controls.
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PMID:Therapeutic regimens in acute experimental pancreatitis in rats: effects of a protease inhibitor, a beta-agonist, and antibiotics. 747 69

Three hundred sixty Sprague-Dawley rats were allocated into four groups, according to different content of a 24-h i.v. infusion performed 1 h after intrabiliary injection of enterokinase/sodium taurocholate to induce acute pancreatitis (AP): (1) Saline; (2) 5 micrograms/kg/h nafamostat mesilate (FUT-175); (3) 10 micrograms/kg/h FUT-175; and (4) 25 micrograms/kg/h FUT-175. Peritoneal fluid was removed and exchanged with 1 mL 3.33 M fluorescein-isothiocyanate-conjugated (FITC) dextrans of 4000-40,000 Dalton. Serial blood samples were withdrawn and examined for FITC-dextrans, phospholipase A2 (PLA2), blood gases, amylase, and lipase. As compared to control (55%), FUT-175 brought about a lower (5 micrograms/kg/h: 25%) or no mortality (10 and 25 micrograms/kg/h), and a milder histological and biochemical evidence of AP. Untreated animals with PLA2 values over two times the standard deviation showed a respiratory distress. Further, unlike group 1, FUT-175 doses as low as 5 micrograms/kg prevented the increase in peritoneal permeability to small-size molecules (up to 20,000 Dalton). In a second experiment under the same drug protocol, 1000 U/mL of PLA2 and 2 mL of pancreatitis ascites were instilled ip. Peritoneal permeability to FITC-dextrans up to 30,000 Dalton and to PLA2 significantly increased in the saline group and in the 5 micrograms/kg FUT-175 group. However, 10 micrograms/kg and 25 micrograms/kg FUT-175 doses prevented such phenomenon. In conclusion, FUT-175 proves to be a potent antiprotease molecule with a biochemical activity also against PLA2 in vivo and prevents significant transperitoneal-blood access of pancreatic enzymes.
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PMID:Nafamostat mesilate on the course of acute pancreatitis. Protective effect on peritoneal permeability and relation with supervening pulmonary distress. 752 62

Two-hundred Wistar rats were allocated to 4 groups. The groups, 3 representing our acute pancreatitis model induced by intrabiliary injection of a trypsin/enterokinase mixture, were studied as follows: (A) no treatment; (B) given a daily 30-ml enema with 20 mg/kg rifaximin; (C) given a daily 30-ml enema with 20 mg/kg rifaximin plus lactitol 0.5 g/kg, and (D) given a daily 30-ml enema with warm saline. A further group of healthy rats was given an intrabiliary injection of 0.15 ml saline. Sacrifices were made after 6, 12, 24, 48 and 72 h of observation. Serial blood samples were drawn to measure pancreatic enzymes and endotoxin. At sacrifice, ascites, lymph nodes, pancreas, spleen, portal vein blood, arterial blood and bile were obtained for bacteriological culture. Both enema treatments brought about a significant improvement in survival. Enema treatments did not affect the serum level of pancreatic enzymes. A time-course increase in endotoxin level was observed in untreated rats. However, significantly decreased levels were observed after both enema treatments. Overall, ascites was the sample most frequently infected. Lymph nodes contiguous to the gut were found to be infected more frequently than those close to major vessels. The histological pancreatic damage was of a significantly lesser degree in both enema treatment groups. Virtually all severe necrotico-hemorrhagic pancreatic lesions were associated with bacterial infection. These data suggest that bacterial translocation plays a relevant role in the outcome of experimental necrotizing pancreatitis. Intra-abdominal spread and lymphatics seem to be the pathways most likely involved in such processes. Colonic cleansing by non-absorbable antibiotics and lactitol seems to exert a beneficial effect on the supervening infection of experimental necrotizing pancreatitis.
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PMID:Bacterial translocation in the course of acute pancreatitis: beneficial role of nonabsorbable antibiotics and lactitol enemas. 891 7

Activation of trypsinogen is thought to trigger the autodigestive process in acute pancreatitis. The lysosomal enzyme cathepsin B was suggested to cause the activation of trypsinogen because it is known that cathepsin B is able to activate trypsinogen in special circumstances and that lysosomal and digestive enzymes are colocalized within intracellular vacuoles in the early stage of pancreatitis. As yet this hypothesis has been difficult to prove because activated trypsin is difficult to quantify in pancreatitis by conventional enzymatic measurements. We therefore employed an ELISA for trypsin activating peptide (TAP), which is a small peptide cleaved during the activation of trypsinogen and can be determined reliably. Supraphysiological concentrations of cerulein (1 nM-1 microM) resulted in a marked increase in TAP in freshly isolated pancreatic acinar cells, indicating activation of trypsinogen. This activation as determined by the TAP increase was significantly reduced by the serine protease inhibitor Fut-175 but not by the cathepsin B inhibitors E-64 and NCO-700. The concentrations of NCO-700 and E-64 abolished the cathepsin B activity of pancreatic acinar cells but did not significantly reduce the trypsin activity (after enterokinase preincubation); correspondingly the concentrations of Fut-175 used abolished the trypsin activity but did not reduce the cathepsin B activity. The results indicate that an autoactivation of trypsin rather than an activation of trypsinogen by cathepsin B triggers trypsin activation by supramaximal cerulein concentrations.
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PMID:Inhibition of cathepsin B does not affect the intracellular activation of trypsinogen by cerulein hyperstimulation in isolated rat pancreatic acinar cells. 943 69

Pancreatic proteases are secreted in acute pancreatitis, but their contribution to associated lung injury is unclear. Applying models of mild edematous (intravenous caerulein) and severe necrotizing (intraductal glycodeoxycholic acid) pancreatitis in rats, we showed that both trypsinogen and trypsin concentrations in peripheral blood, as well as lung injury, correlate with the severity of the disease. To isolate the potential contribution of proteases to lung injury, trypsin or trypsinogen was injected into healthy rats or trypsinogen secreted in caerulein pancreatitis was activated by intravenous enterokinase. Pulmonary injury induced by protease infusions was dose dependent and was ameliorated by neutrophil depletion. Trypsinogen activation worsened lung injury in mild pancreatitis. In vitro incubation of leukocytes with trypsinogen showed that stimulated leukocytes can convert trypsinogen to trypsin. In conclusion, this study demonstrates that the occurrence and severity of pancreatitis-associated lung injury (PALI) corresponds to the levels of circulating trypsinogen and its activation to trypsin. Neutrophils are involved in both protease activation and development of pulmonary injury.
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PMID:Trypsin and activation of circulating trypsinogen contribute to pancreatitis-associated lung injury. 1056 7

In healthy subjects, the 3 known pancreatic trypsinogens, which are endopeptidases belonging to the chymotrypsin superfamily, are activated by enterokinase and partial autoactivation in the duodenum. The premature activation of trypsinogen in the pancreatic interstitium, with the subsequent activation of other pancreatic zymogens, is believed to lead to the autodigestion of the gland, this being the first event in acute pancreatitis. The mechanisms that lead to trypsinogen, activation in acute pancreatitis are largely unknown. However, ischemia, hypercalcemia and the activation of cathepsin B (by cholecystokinin) are thought to be of importance. The easiest and most reliable way to assess trypsinogen activation is the measurement of the activation peptide, TAP, in urine, plasma, pancreatic tissue or ascitic fluid. In the animal model of acute pancreatitis, TAP in ascites and pancreatic tissue has been shown to correlate with the presence and extent of necroses. It has proven to be a good marker for the severity of pancreatitis and is a useful marker in examining the pathophysiology and possible treatment modalities in the animal model of acute pancreatitis. Studies on TAP in human acute pancreatitis were most commonly focused on urinary TAP. Within a 48-hour time frame after the onset of the disease, TAP was a good predictor of the severity of acute pancreatitis. The main advantage over other markers, such as CRP, is that TAP is the earliest marker of necrosis to be increased. Also, increased levels of TAP in ascitic fluid were shown to correlate well with pancreatic necroses. In our experience, plasma TAP was found to have a "diagnostic window" within the first 3 days predicting pancreatic necroses. Positive TAP gave a very good positive prediction and a high specificity towards the development of pancreatic necroses, but did not differ between necrotizing pancreatitis with systemic complications or uncomplicated necrotizing pancreatitis. We therefore think that plasma TAP is a very good marker for local complication in acute pancreatitis and its routine measurements may help to identify patients at a high risk within the first days of the disease.
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PMID:Mechanism and role of trypsinogen activation in acute pancreatitis. 1057 41

Autodigestion by proteolytic enzymes is thought to represent the critical mechanism by which acute pancreatitis is initiated. Where and why pancreatic proteases, which are physiologically stored and secreted as inactive precursor zymogens, are activated within the pancreas has remained controversial. Here we present data which indicate that: the lysosomal protease cathepsin B can activate trypsinogen in vitro in a manner that is similar to trypsinogen activation by enterokinase; that cathepsin B colocalizes with trypsinogen in the secretory compartment of the rat pancreas and of the human pancreas; that trypsinogen activation begins in a secretory compartment that is distinct from mature zymogen granules; and that the inhibition of cathepsin B can either increase or decrease premature trypsinogen activation depending on the concentration of the inhibitor, its specificity and its site of action in the pancreatic acinar cell. These observations elucidate some of the complex relations between cysteine and serine proteases in the pancreas with respect to their mechanisms of activation, their subcellular sites of action, and their possible role in the onset of pancreatitis.
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PMID:The role of cysteine proteases in intracellular pancreatic serine protease activation. 1084 66

Hyperthermia, raising the body temperature from normal to above 40 degrees C, has been shown to prevent pancreatitis in an experimental animal model of the disease, but the underlying cellular mechanisms of this protection remain unknown. We induced controlled hyperthermia in either laboratory rats and isolated pancreatic acini or, alternatively, raised the temperature of pancreatic homogenates in vitro from 37 to 41 degrees C. In vitro controlled hyperthermia of up to 41 degrees C increased the autoactivation-induced and enterokinase-induced trypsinogen activation as well as free trypsin activity. Conversely, in whole animal studies and in living acinar cells hyperthermia reduced or abolished premature intracellular trypsinogen activation in a time- and temperature-dependent manner and this protective effect was independent of either de novo protein synthesis, interference with acinar cell signal transduction, or confirmational changes in pancreatic trypsinogen. We conclude that hyperthermia, in a manner that is independent of the synthesis of pancreatic chaperone or heat shock proteins, can directly abolish the earliest initiating event involved in the onset of pancreatitis, namely the premature and intracellular activation of digestive zymogens.
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PMID:Effect of hyperthermia on premature intracellular trypsinogen activation in the exocrine pancreas. 1126 86

Hereditary pancreatitis has been found to be associated with germline mutations in the cationic trypsinogen (PRSS1) gene. Here we report a family with hereditary pancreatitis that carries a novel PRSS1 mutation (R122C). This mutation cannot be diagnosed with the conventional screening method using AflIII restriction enzyme digest. We therefore propose a new assay based on restriction enzyme digest with BstUI, a technique that permits detection of the novel R122C mutation in addition to the most common R122H mutation, and even in the presence of a recently reported neutral polymorphism that prevents its detection by the AflIII method. Recombinantly expressed R122C mutant human trypsinogen was found to undergo greatly reduced autoactivation and cathepsin B-induced activation, which is most likely caused by misfolding or disulfide mismatches of the mutant zymogen. The K(m) of R122C trypsin was found to be unchanged, but its k(cat) was reduced to 37% of the wild type. After correction for enterokinase activatable activity, and specifically in the absence of calcium, the R122C mutant was more resistant to autolysis than the wild type and autoactivated more rapidly at pH 8. Molecular modeling of the R122C mutant trypsin predicted an unimpaired active site but an altered stability of the calcium binding loop. This previously unknown trypsinogen mutation is associated with hereditary pancreatitis, requires a novel diagnostic screening method, and, for the first time, raises the question whether a gain or a loss of trypsin function participates in the onset of pancreatitis.
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PMID:Hereditary pancreatitis caused by a novel PRSS1 mutation (Arg-122 --> Cys) that alters autoactivation and autodegradation of cationic trypsinogen. 1171 9


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