Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.4 (trypsin)
 42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied the effect of four graded doses of SMS 201-995, a synthetic octapeptide somatostatin analogue (27, 80, 240, and 720 ng/kg/h) on the basal and secretin-plus-cerulein-stimulated exocrine pancreatic function and pancreatic polypeptide (PP) release in five healthy volunteers. Duodenal fluid secretion and bicarbonate output under basal and stimulated conditions were not significantly affected by any dose of SMS. The basal and stimulated enzyme secretion were decreased in a non-dose-dependent manner by all SMS doses used in the study and showed a 75% inhibition of the secretin-plus-cerulein-stimulated trypsin and amylase output. The cerulein-stimulated PP release was significantly suppressed by all four SMS doses. SMS appears to be a strong inhibitor of pancreatic enzyme secretion, at the same time affecting the PP release.
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PMID:Effect of a new somatostatin analogue on pancreatic function in healthy volunteers. 243 63

The diagnostic value of serum enzyme provocative tests (SEP) is disputed. In particular, the specificity of the test has not been adequately investigated. New interest in the test has arisen with the introduction of pancreas-specific serum enzyme tests. It has been shown that a poststimulatory increase of serum enzymes is found in chronic pancreatitis with well preserved exocrine function, but also in healthy individuals and particularly cigarette smokers. Recently it has been postulated that the lack of a poststimulatory enzyme response is typical of advanced chronic pancreatitis. We investigated the effect of secretin (1 CU/kg i.v.) on serum levels of amylase, pancreasisoamylase, lipase and trypsin for 30 minutes in 48 volunteers without pancreatic disease (19 non-smokers, 19 smokers and 10 patients with hypoxemia). Mean values of all enzymes were significantly higher after stimulation. Enzyme response of trypsin and lipase was more pronounced than that of amylase or pancreasisoamylase. However, depending on the enzyme studied, no significant increase of serum values was found in 47.4% to 89.5% of smokers, 26.3 to 68.4% of non-smokers and 10 to 50% of patients with hypoxemia. The marked variability of enzyme response in controls demonstrates the low specificity of this test. Therefore, SEP are of no diagnostic value in pancreatic disease.
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PMID:[Changes in the serum pancreas enzyme following i.v. stimulation with secretin in subjects with a normal pancreas]. 243 65

Thirty-six infants suffering from gastrointestinal diseases during infancy were evaluated for exocrine pancreatic function by means of the pancreozymin-secretin test. Duodenal fluid volume, protein content, and content and peak-specific activity of amylase, lipase, and trypsin were determined following intravenous administration of either pancreozymin (CCK) or secretin. Seven infants receiving long-term parenteral nutrition and 17 infants receiving oral feedings and exhibiting first-degree malnutrition in association with chronic diarrhea underwent testing. Results were compared to those of a group of 12 age-matched infants with chronic diarrhea and weight loss. Four patients receiving total parenteral nutrition (TPN) suffered from severe short bowel syndrome and three had intractable diarrhea of infancy. The total duration of TPN ranged from 1.5-12 months, and the period of exclusive TPN in the absence of oral feedings ranged from 1-4 months. The heights, weights, and weight-for-height relationships were at or above the fifth percentile for all seven infants. The weight-for-height relationship of each patient in the control group was above the fifth percentile, while that of all malnourished infants was below the fifth percentile. No significant difference was found in the volume of fluid collected following either CCK or secretin administration. The content and concentration of amylase and lipase were lower in those patients receiving TPN. The levels were statistically significant (p less than 0.05) following secretin administration. In contrast, the peak-specific activity and total trypsin content, as well as protein content, was not significantly different in patients receiving TPN, controls, and malnourished patients.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Nutrition and exocrine pancreatic function in infancy: effects of total parenteral nutrition and first degree malnutrition. 244 51

The action of synthetic human secretin, which differs in two amino acid residues from porcine secretin, was compared with synthetic porcine secretin in 6 healthy volunteers. Pancreatic secretion was assessed by a marker perfusion technique and plasma secretin concentrations were assessed by a specific radioimmunoassay. Increasing doses of either human or porcine secretin produced increasing bicarbonate output (p less than 0.01), whereas trypsin and lipase were not stimulated over basal. The highest doses of secretin induced a significant increase in pancreatic amylase secretion. The two secretin preparations were found to be equipotent with respect to pancreatic secretion and plasma kinetics. Significant increases of plasma secretin were observed after a steak meal in 15 volunteers (p less than 0.001). When human secretin was infused at postprandial concentrations, significant increases in pancreatic bicarbonate output were observed (p less than 0.05). We conclude (a) that the substitution of two amino acids in human secretin does not affect biologic activity and plasma metabolism of the compound; (b) secretin does not stimulate pancreatic enzyme secretion at physiologic concentrations; and (c) the stimulatory effects of secretin on pancreatic amylase remain to be elucidated. The study suggests that human secretin is a true hormone.
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PMID:Human secretin. Biologic effects and plasma kinetics in humans. 244 46

In an effort to develop a model of chronic alcoholic pancreatitis in Sprague-Dawley rats fed a nutritionally adequate diet, 3 groups of 15 animals each were fed Wayne Rodent-Blox ad libitum, Lieber-DeCarli diet with 40% of carbohydrate calories replaced by ethanol ad libitum and isocaloric amounts of Lieber-DeCarli diet respectively for a period of 18 months. Rats were anesthetized and basal and secretin-stimulated pancreatic juice was obtained. Pancreatic glands were isolated and divided into portions for histology, biochemical analyses, and cell fractionation. The homogenate, zymogen granule fraction, mitochondrial-lysosomal fraction, microsomal fraction and postmicrosomal supernatant as well as aliquots of pancreatic juice were analyzed for cathepsin B, acid phosphatase, beta-D-glucoronidase, arylsulphatase and leucine naphthylamidase. All of the ethanol-fed animals developed morphological changes akin to human chronic pancreatitis. There were focal areas of parenchymal degeneration with fibrosis, protein plug formation and tubular complexes. In the pancreatic tissue of animals fed ethanol, total protein, trypsinogen (and free trypsin) were increased and amylase was decreased. While acid phosphatase was increased in all of the particulate fractions, cathepsin B was increased in the zymogen granule and mitochondrial-lysosomal fractions. Basal and post-secretin pancreatic juice did not show a significant increase in digestive or lysosomal enzymes. It is suggested that focal degenerative changes may be due to trypsin generated by intracellular activation of digestive enzymes by lysosomal enzyme cathepsin B.
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PMID:Alcoholic pancreatitis in rats fed ethanol in a nutritionally adequate liquid diet. 244 6

A study conducted on intact and castrated male rats with cannulated biliary-pancreatic ducts has shown that long-term protein deficiency in the ration leads to decreased secretion of pancreatic juice, lowers activity of amylase, alkaline ribonuclease, trypsin, lipase in the juice, and changes pancreatic response to the action of secretin, pancreozymin or their mixture, that is especially pronounced in the castrated rats.
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PMID:[Response of the rat pancreas to the effects of secretin and pancreozymin under conditions of different nutrition]. 244 64

The mechanisms of pancreatic adaptation to dietary changes and whether these changes are reflected in the serum are not fully understood. The present study investigates secretagogue-induced release of digestive enzymes from dispersed pancreatic acini as well as the concentrations of these enzymes in serum and pancreas after adaptation to a high protein diet. Adult rats were fed an 8.5% casein diet ad libitum. After 14 d the rats were divided into three groups and fed isoenergetic diets constituting 8.5, 24 or 40% protein for an additional 6 d. No significant differences in final body weight or pancreatic weight were observed among the groups of rats. Rats adapted to the 40% protein diet showed significantly higher trypsin and chymotrypsin activity in pancreatic homogenates than rats fed the 8.5% protein diet. These changes in pancreatic enzyme content were not reflected in serum. Pancreatic acini isolated from the 8.5% protein group showed a markedly reduced responsiveness to cholecystokinin (CCK-8), secretin- and carbachol-induced enzyme release in comparison to the other two dietary groups, although basal enzyme release was the same in all groups. These results indicate that the secretion of pancreatic enzymes following a physiological stimulus is affected by a low protein, high carbohydrate diet.
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PMID:Secretagogue-induced enzyme release from the exocrine pancreas of rats following adaptation to a high protein diet. 245 Sep 76

This study describes the effect on the function and structure of the saline-perfused cat pancreas of factors implicated in the pathogenesis of pancreatitis (bile acid, ethanol, pancreatic enzymes) after their addition to the perfusion fluid or their instillation into the pancreatic duct. Instillation of trypsin or chenodeoxycholic acid, but not ethanol, into the pancreatic duct resulted in a profound suppression of secretory function. The leakage of perfusion fluid and amylase from the gland was also abruptly increased. Intraarterial perfusion of trypsin also inhibited secretin-induced flow and cholecystokinin evoked enzyme secretion. Intraarterial bile acid inhibited fluid flow but augmented enzyme secretion in a concentration-dependent manner. In addition, massive or focal parenchymal necrosis was caused by sustained intraarterial perfusion of bile acid or trypsin, respectively. Elastase and phospholipase A had little influence on pancreatic function or structure when added to the perfusion fluid. These findings show that pancreatic structure and function can be disturbed by potentially toxic factors administered not only via the ductal system but also via the vascular route, and consequently suggest that an "internal reflux" mechanism could be involved in the pathogenesis of pancreatitis in addition to a "ductal reflux" mechanism.
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PMID:Analysis in the isolated perfused cat pancreas of factors implicated in the pathogenesis of pancreatitis. 245 94

The present study investigates the effects of nicotine treatment on exocrine pancreatic function. Adult male, Sprague-Dawley rats received nicotine via a time-release pellet, at a rate of 1.65 micrograms/min for 3 weeks. At the end of the experimental period, it was observed that although nicotine did not affect final body or pancreatic weight, the activities of amylase, trypsin, and chymotrypsin in pancreatic homogenates from nicotine-treated rats were 51, 29, and 35% higher, respectively, than in controls. Levels of immunoreactive cationic trypsin(ogen) were significantly higher in pancreatic homogenates and serum from nicotine-treated rats as compared with controls. In addition, concentrations of mRNA, encoding for pancreatic amylase, were higher in pancreatic homogenates from the nicotine-treated rats than in controls. In dispersed pancreatic acini isolated from nicotine-treated rats, basal secretion of amylase, trypsinogen, and chymotrypsinogen was 50% higher than controls and enzyme release following CCK-8 (100 pM), secretin (1 microM), and carbachol (7.5 microM) stimulation was also significantly higher. These data indicate that nicotine treatment, at levels comparable to those expected in moderate cigarette smokers, increases the content of digestive enzymes in rat pancreas, as well as their basal and secretagogue-induced release.
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PMID:Altered exocrine pancreatic function in rats treated with nicotine. 246 Sep 70

In order to investigate whether the human pancreas is capable of adapting to a diet with high-carbohydrate, low-fat, and normal protein content, 10 healthy volunteers were given a defined elemental diet (60% of calories as carbohydrates, 22% as fat, and 18% as protein) for 7 d. For the next 7 d they received an elemental diet with a further increased carbohydrate content (76% of calories) and a decreased fat content (10% of calories). A complete secretin-pancreozymin test was carried out at the end of the first wk and at d 14. The results show that an increase in dietary carbohydrate does not provoke an adaptational response of stimulated secretion rates of amylase, trypsin, and chymotrypsin in humans, as expected from animal experiments.
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PMID:High amount of dietary carbohydrate does not cause an adaptational increase of stimulated human pancreatic amylase secretion. 247 55


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