Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.21.1 (chymotrypsin)
 10,938 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied the effects of small-bowel resection and bypass on pancreatic function in rats subjected to a 50% distal resection (DR), a 50% proximal resection (PR), a 50% jejunal bypass (BP) or an intestinal transection (SH) (controls). Duodenal contents were collected after cannulation (under basal conditions). Afterwards, an in vivo duodenal perfusion was made using a glucose/saline solution and perfusate was collected for 1 h. Following this, a cholecystokinin (CCK) solution was injected into the jugular vein (1 U/kg body wt.) and perfusion continued for another 1 h. Basal duodenal volume only increased in rats with a PR, and no significant changes occurred in protein content. In basal conditions, no decreases in amylase, lipase, trypsin, or chymotrypsin activities after DR, PR or BP were detected. When animals were subjected to a perfusion and CCK stimulation, no significant changes occurred in animals with BP; the volume was maintained in rats with PR and DR but a decrease in protein and enzymatic contents was found. We concluded that, in basal conditions, the lack (resections) or exclusion (BP) of 50% of the small bowel does not negatively affect the digestive function. When however, a sustained activity is required, the extirpation of intestinal surface provokes a fall in enzymatic activities and is not modified if only the intestinal transit is suppressed, as occurs in the cases of BP.
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PMID:Comparative effect of distal and proximal intestinal resection and bypass on the rat exocrine pancreas. 170 46

It is believed that activation of zymogen proteases occurs in the early development of acute pancreatitis. This hypothesis was proved on subcellular fractions of rat pancreas after induction of pancreatitis by infusion of high doses of cerulein for 2 h. Secretory enzyme activities were measured spectrophotometrically in subcellular fractions obtained by differential ultracentrifugation. Additionally, trypsin and chymotrypsin activities were detected by enzyme blots after isoelectric focusing. Finally immunoblotting (Western-blot analysis) for amylase, lipase, trypsin/ogen, and chymotrypsin/ogen was carried out on fractions separated by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). In cerulein pancreatitis, subcellular fractions of secretory granules and vacuoles showed significant amounts of free trypsin and chymotrypsin activities compared with controls. The presence of free activities of serine proteases was paralleled by the appearance of numerous low molecular weight peptides detected by 2-dimensional electrophoresis and SDS-PAGE, which in part represented proteolytically cleaved secretory proteins. It is concluded that the intracellular activation of serine proteases that occurs in cerulein pancreatitis could contribute to further acinar cell destruction.
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PMID:Evidence of intracellular activation of serine proteases in acute cerulein-induced pancreatitis in rats. 170 79

The effects of the removal of bile from the proximal intestine on pancreas, plasma cholecystokinin (CCK) concentration, and duodenal content of CCK were examined in rats. Bile was excluded from the duodenum and introduced into the distal ileum through a silastic cannula for 7 days. Pancreatic juice was maintained to be normally secreted into the duodenum. After 7-day bile diversion, plasma CCK concentration and duodenal CCK content were significantly increased in bile-diverted rats. Trypsin content in the proximal intestine in bile-diverted rats was one-half that in control. Pancreatic wet weight, protein content, and DNA content in the pancreas were slightly increased, and lipase content was slightly decreased, by bile diversion, but none of these changes was statistically significant. Amylase content significantly decreased and chymotrypsin content significantly increased in bile-diverted rats. Intragastric administration of camostate (trypsin inhibitor) significantly increased plasma CCK concentration in both bile-diverted and control rats, and the net increase was much greater in bile-diverted rats than in control rats. In conclusion, bile diversion increased duodenal CCK content and increased the CCK response to luminal stimulant.
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PMID:Absence of luminal bile increases duodenal content of cholecystokinin in rats. 170 4

The essential role of cholecystokinin (CCK) in pancreatic regeneration after pancreatitis or resection has been supposed, but not yet clearly demonstrated. In rats, 6-8 weeks after 60% distal resection of the pancreas a gradual increase in pancreatic weight and contents of DNA, protein, trypsin, chymotrypsin and amylase, occurred (there was no increase in lipase); Pancreatic regeneration stopped thereafter. Nonparallel increases in enzyme values were similar to those seen after CCK administration. Indeed, basal CCK levels increased significantly by the 6th week and declined thereafter. A one month s.c. administration of CCK-octapeptide (CCK-8) (3 x 300 ng/kg/d) accelerated regeneration in the first month, but it had almost no effect during the second or third postoperative months. A two week s.c. administration of a specific CCK antagonist, CR 1409 (3 x 4 mg/kg/d) totally prevented regeneration by the fifth and sixth weeks, but did not diminish pancreatic weight or DNA and protein contents during the first two weeks. Alcohol administration (12 g/kg/d) reduced CCK release and prevented pancreatic regeneration during the three-month experimental period. These data indicate that CCK has an essential role in pancreatic regeneration and that the deleterious effect of alcohol on regeneration involves inhibition of CCK release.
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PMID:Essential role of cholecystokinin in pancreatic regeneration after 60% distal resection in rats. 802 68

1. Body weight and the weight of the digestive organs and activities of some digestive enzymes were determined from hatching to 23 d of age. 2. Relative daily growth rate peaked at 11 d of age (22% gain/d) and then decreased gradually. 3. The vitelline residue was decreased rapidly from 4.6 g at hatching to negligible values from 4 d of age. 4. Maximal allometric growth of the pancreas and small intestine was 4-fold and that of liver 2-fold greater than that of the body. 5. Activities (units/kg body weight) of the digestive enzymes measured in the pancreas and intestinal contents increased with age. In the pancreas maximal values were attained on day 8 for amylase and lipase and 11 for trypsin and chymotrypsin. In the small intestine maxima were attained on day 4 for lipase, 11 for trypsin and chymotrypsin and 17 for amylase. 6. The development of secretion of digestive enzymes in the post-hatched chick could be a limiting factor in digestion and subsequently in food intake and growth.
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PMID:Growth and development of the digestive organs and some enzymes in broiler chicks after hatching. 171 7

The existence of negative feedback inhibition of human pancreatic enzyme secretion by proteases is controversially discussed. We have recently demonstrated that jejunal application of porcine pancreatic extracts, in a dose commonly used to treat digestive insufficiency, stimulated rather than inhibited, human pancreatic enzyme secretion. We have now studied the influence of duodenal application of high concentrations of either pure trypsin or porcine pancreatic extracts with trypsin-equivalent activity, on human pancreatic enzyme secretion. Twenty-three male volunteers were intubated with a gastric tube and a two-lumen jejunal tube to collect secretions separately via the first and third tubes and to perfuse either pure trypsin or porcine pancreatic extracts distal to the pylorus via the second tube. PEG-4.000 was continuously perfused via the second tube to correct for losses of volume. Volunteers received PEG alone during the first hour, phenylalanine during the second, PEG alone again during the third, and either phenylalanine together with trypsin or porcine pancreatic extracts during the fourth h. Activities of lipase, amylase, and chymotrypsin were measured in 15-min fractions. In addition, human lipase secretion was measured with an enzyme immunoassay, which does not crossreact with porcine lipase. Plasma cholecystokinin (CCK) was measured using a sensitive bioassay, which utilizes amylase release by isolated rat pancreatic acini. Perfusion of the duodenum with phenylalanine caused a statistically significant stimulation of enzyme secretion. This stimulation could be inhibited by high concentrations of pure trypsin. In contrast, application of porcine pancreatic extracts, which contained the equivalent activity of trypsin, caused further increases of lipase secretion when compared to phenylalanine alone.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Influence of exogenous application of pancreatic extracts on endogenous pancreatic enzyme secretion. 172 24

The effect on steatorrhoea of a pH-sensitive enteric-coated pancreatic preparation (Eurobiol 25,000) was compared with a conventional pancreatic enzyme preparation (Eurobiol) in six adult patients with exocrine pancreatic insufficiency. In addition, the fate of orally ingested pancreatic enzymes in the upper digestive tract was evaluated by measuring gastric and duodenal pH, amount of enzymes in the stomach, duodenal enzyme output, and fat absorption at the angle of Treitz for the 4 hours following a standard meal. When compared with placebo, Eurobiol and Eurobiol 25,000 reduced daily faecal fat excretion by 24% (not significant) and 43% (P less than 0.05), respectively. With the conventional preparation, enzyme output and fat absorption at the duodeno-jejunal flexure were significantly improved (P less than 0.05). Marked inter-individual differences in duodenal enzyme recovery (lipase 3% to 80%; chymotrypsin 26% to 100%) and, consequently, in the reduction of steatorrhoea (0% to 67%) were observed, with the gastric emptying rate emerging as a key determinant factor. With the enteric-coated preparation, enzyme output and fat absorption at the duodenojejunal flexure were not significantly improved. Discrepancy between the marked reduction of faecal fat excretion and the low duodenal enzyme recovery could indicate that enzyme delivery from microtablets occurs further down in the small bowel. Efficacy of enteric-coated preparations could be enhanced by adding unprotected enzymes, especially in patients with rapid gastric emptying.
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PMID:Fate of orally ingested enzymes in pancreatic insufficiency: comparison of two pancreatic enzyme preparations. 177 47

Pancreatic exocrine secretion was estimated in 180 normal control patients, free of abdominal and pancreatic disease, aged from 16 to 83 years. Duodenal juice was collected in two 15-min fractions after a single intravenous injection of 1 U/kg secretin + 3 U/kg CCK. Volume, maximal concentration and output of bicarbonate, lipase, phospholipase and chymotrypsin were estimated as well as minimal concentration and output of chloride and calcium. Each parameter was plotted against age, either individually or after separation into two age groups. Volume linearly increased up to the 3rd decade, and thereafter linearly decreased. Bicarbonate secretion paralleled fluid secretion and also decreased after the 3rd decade. The changes in chloride and calcium concentrations were different: concentrations linearly increased after the 3rd decade. Calcium concentration linearly increased with age (p less than 0.02) while chloride output was unchanged. The three enzymes that were studied linearly decreased in concentration as well as in output with age from the 3rd decade (p less than 0.02). Protein secretion decreased before water and bicarbonate secretion. One can conclude that pancreatic secretion changes in humans with age. Aging alters pancreatic secretion, through a decrease in flow rate, bicarbonate and enzyme secretion while calcium concentration is enhanced. Although not requiring substitutive therapy in the whole population, individual cases of pancreatic exocrine insufficiency might be explained by aging, without malnutrition.
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PMID:Changes in pancreatic exocrine secretion with age: pancreatic exocrine secretion does decrease in the elderly. 181 45

Deacetylation of octa-O-acetylsucrose (1) with Alcalase or protease N gave the 2,3,4,6,3',4',6'-hepta-acetate (2) as the initial major product with the 2,3,4,6,3',4'-hexa-acetate (3) as the subsequent main product. The 2,3,4,1',3',4',6'-hepta-acetate (5) was obtained from 1 by the action of lipase OF or lipase AP6, and the 2,3,4,6,1',3',6'-(4) and 2,3,4,6,1',3',4'-hepta-acetate (7) by the action of Candida lipase and chymotrypsin, respectively. The 2,3,6,1',3',4',6'-hepta-acetate (6) was formed from 5 by acyl migration.
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PMID:Regioselective enzymic deacetylation of octa-O-acetylsucrose: preparation of hepta-O-acetylsucroses. 181 3

Eight-cell, zona pellucida-intact mouse embryos were exposed to the following substances or procedures that have been reported to have germicidal effects to determine if the embryos would survive and develop under in vitro conditions: the photosensitive substances hematoporphyrin, hematoporphyrin derivative, 8-methoxypsoralen, 4,5',8-trimethylpsoralen, and thiopyronine; the enzymes lipase (0.5%), phospholipase C (2 U/ml), chymotrypsin (0.5%), and trypsin (0.5%); pH 5.0; and helium/neon laser light, visible light, ultraviolet A light, and ultraviolet C light. Under the conditions used, embryos were not adversely affected by hematoporphyrin and/or helium/neon laser light; methoxypsoralen and/or ultraviolet A light; lipase; trypsin; pH 5.0 for 20 min; and visible light. Variable results were obtained from hematoporphyrin derivative with laser light. Thiopyronine, trimethylpsoralen in combination with ultraviolet A light, and ultraviolet C light killed embryos, and chymotrypsin and phospholipase C were harmful at 10- and 15-min exposure times, respectively.
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PMID:Investigation of some antimicrobial procedures on the in vitro development of early murine embryos aimed toward developing methods for the disinfection of mammalian embryos prior to transfer. 182 23


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