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)

To investigate the pathophysiology of steatorrhea in primary biliary cirrhosis, the severity of steatorrhea, small bowel histology and function, cholestasis, exocrine pancreatic secretion and liver histology were studied. Twenty-four primary biliary cirrhotic patients had a quantitative stool fat collection, serum bilirubin and alkaline phosphatase and liver biopsies. From this group, ten had further studies: a small bowel biopsy (n = 7); a D-xylose test (n = 9); measurement of pancreatiobiliary concentrations and outputs after intravenous cholecystokinin (n = 10); essential amino acid perfusion of the duodenum (n = 9), and eating a test meal (n = 7). D-xylose absorption was normal, and only one patient had a minimal small bowel mucosal abnormality. Pancreatic lipase outputs in response to cholecystokinin were low in two primary biliary cirrhotic patients, but were greater than 10% of normal. Postprandial lipase outputs were normal except in one patient who had abnormal duodenal acidification. Mean enzyme outputs in primary biliary cirrhotic patients were normal in response to essential amino acid perfusion; but 6 had low lipase and 5 had low trypsin outputs which were associated with decreased bile acid outputs (p less than 0.03). Severity of steatorrhea was associated with reduced bile acid outputs and concentrations (r = 0.82; p less than 0.0001), degree of cholestasis (serum bilirubin; r = 0.88; p less than 0.001) and advanced histologic stages (p less than 0.005). Severe intraluminal bile acid deficiency combined with a submaximal intraluminal stimulus (essential amino acids) may be associated with decreased exocrine pancreatic secretion in primary biliary cirrhosis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Pathogenesis of steatorrhea in primary biliary cirrhosis. 241 48

In order to study the question as to whether the enzyme ratios in the pancreatic juice change with the secretion rate, we analysed the enzyme outputs of 20 healthy volunteers under combined stimulation with varying doses of cholecystokinin (0; 0.5; 1.0 or 1.3 IDU X kg-1 X h-1), administered in random order, plus a constant dose of secretin (0.5 CU X kg-1 X h-1). The outputs of the individual enzymes correlated significantly (p less than 0.0001) to the corresponding amylase outputs in the form of power model regressions. Mathematical transformation of these curvilinear regressions permitted a comparison of their courses. This analysis revealed that the enzyme ratios in the pancreatic secretion change continuously at increasing outputs in favour of lipase greater than chymotrypsin greater than amylase. The shift in the ratio of lipase to trypsin and to amylase and that of chymotrypsin to amylase was significant (p less than 0.01).
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PMID:Output-dependent non-parallel enzyme secretion of the human pancreas. 241 63

This study set out to examine the effects of a Ca++ channel blocker, verapamil, on pancreatic exocrine secretion because of the known relationship between amylase secretion and intracellular Ca++. Pancreatic secretion was stimulated in dogs by infusing secretin and cholecystokinin. Verapamil was found to inhibit the secretion of amylase but to have no effect on lipase, trypsin, or total protein. There was no effect on the secretion of water and bicarbonate. To determine the possible physiologic significance of these findings, the pancreas was stimulated by a meat meal, and verapamil was found to inhibit amylase secretion again and in addition to inhibit the secretion of water and bicarbonate. The results suggest that verapamil has an inhibitory effect on amylase secretion by blocking the influx of Ca++ into the acinar cell and has an indirect effect leading to inhibition of water and bicarbonate secretion from the duct cells.
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PMID:The effect of verapamil on pancreatic exocrine secretion. 242 19

The effect of a milk substitute diet containing concentrated soya protein on secretory functions of the abomasum and pancreas and on plasma concentrations of gut hormones and soya antibodies was studied. Sixteen calves aged 12-19 weeks were given a milk substitute in which a major part of the protein source was either soya concentrate (soya diet) or skim milk (control diet). The soya diet was prepared by hot aqueous ethanol extraction of soya bean meal to remove oligosaccharides and inactivate antigenic constituents. Circulatory IgG antibodies against soya proteins were found in all of the calves when they were 16 weeks of age. Their titres increased slightly between 16 and 19 weeks, irrespective of the diet. It seems unlikely that the presence of these antibodies was related specifically to the feeding of the soya concentrate. At slaughter the weight of the gastric mucosa and pancreas and quantities of pancreatic protein together with specific activities of trypsin and chymotrypsin were significantly lower (17, 20, 16, 30 and 36%, respectively) with the soya diet. The quantities of enzymes in the gastric mucosa or the specific activity of pancreatic amylase were not affected, whereas that of lipase increased by 26%. Total enzyme activities as well as units per kg live weight gave significant differences only for trypsin and chymotrypsin which were reduced by 43 and 38%, respectively. With the soya diet, fasting concentrations of gastric inhibitory peptide (GIP) and secretin in plasma samples were significantly lower (49 and 34%, respectively). Values of GIP were also lower (54%) 1 h after feeding. In contrast, postprandial values of cholecystokinin (CCK) were 1.4 times greater. No significant differences were found between the two diets for gastrin, vasoactive intestinal peptide (VIP), bovine pancreatic polypeptide (BPP), somatostatine and motilin. In general these observations could be explained, in part, by the more rapid passage of protein and fat from the abomasum to the duodenum following feeds containing soya concentrate. However, these differences in concentrations of gut hormones did not seem to be related to variations in the weights of gastric mucosa and pancreas or activities of pancreatic enzymes.
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PMID:Effect of soya protein on digestive enzymes, gut hormone and anti-soya antibody plasma levels in the preruminant calf. 242 2

Temporary reduction of the exocrine pancreatic secretion may be desirable in various experimental models. In the rat this can be achieved by obstructing the connection between the pancreas and the duodenum. A new, simple technique of pancreatic duct occlusion using metal hemostatic clips is described. The reduction of secretion produced by the procedure was assessed by measuring duodenal protein, amylase, and trypsin during stimulation with cholecystokinin. Stimulated duodenal amylase activity 1 and 4 weeks following duct occlusion was reduced by approximately 80% compared with sham-operated controls, whereas proteolytic activity was reduced by 96 and 60%, respectively. The magnitude and duration of pancreatic insufficiency achieved by this technique is equivalent to that achieved with more complicated methods.
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PMID:Pancreatic duct occlusion in the rat: report and assessment of a new technique. 242 17

A bland procedure, conducted in ice, is described for the extraction with HCl of smooth-muscle-contracting substances from plexus-containing ileal longitudinal muscle (l.m.) sheets obtained mainly from rabbits and some guinea-pigs. The spasmogenic activity in rabbit extracts was distinguished from acetylcholine, histamine and 5-hydroxytryptamine by antagonists; and from prostaglandins, by its insolubility in ether at acid pH and by pretreatment of the animals with indomethacin. The fact that it contracts the separated l.m. of the guinea-pig ileum, whether plexus-containing or plexus-free, and in atropine distinguishes it also from methionine-enkephalin, somatostatin, 13-norleucine motilin, bombesin, and cholecystokinin octapeptide (CCK8). This activity was partially purified, first by several partitions with ether at pH 1.4-2.2 and then by treatment at pH 4.5-5 with lead acetate. The virtual absence of ATP was confirmed by the firefly bioluminescence technique. The guinea-pig-ileum-contracting component in the partially purified extracts was destroyed by pepsin, chymotrypsin and DPCC-treated trypsin, indicating its peptide nature and distinguishing it from oxytocin, vasopressin, bradykinin, etc. In parallel assays the partially purified rabbit extracts were considerably more active than Substance P on jird or rat ascending colons than on the guinea-pig l.m., suggesting the presence of a second spasmogenic component in the extracts. In guinea-pig extracts the partially purified activity was 8-16 times greater when plexus-containing than when plexus-free, pointing to Auerbach's plexus as the source of the activity.
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PMID:Extraction and partial purification of spasmogenic substances in Auerbach's plexus. 242 21

The effects of the cholecystokinin (CCK)-receptor antagonist proglumide, the protease inhibitor gabexate, and the hormones secretin and cholecystokinin-octapeptide (CCK-8) were studied in a model of acute hemorrhagic pancreatitis induced by feeding mice a choline-deficient, ethionine-supplemented (CDE) diet. Injections of gabexate and proglumide from initiation of CDE diet (before induction of pancreatitis) increased survival from 37% (diet alone) to 85 and 75%, respectively, and also ameliorated histological alterations and increases in serum amylase concentration and pancreatic activated trypsin. Secretin had no major beneficial effect. When proglumide or gabexate were given after induction of pancreatitis, proglumide still increased survival to 75%, whereas gabexate no longer did. Injection of nontoxic doses of CCK-8 before proglumide or gabexate injections completely abolished all beneficial effects and also increased the severity of pancreatitis due to CDE diet alone. Blockade of CCK receptors and early inhibition of protease activity may be beneficial in severe acute pancreatitis. Cholecystokinin appears to play a contributory role in the development of pancreatitis.
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PMID:Beneficial effects of cholecystokinin-receptor blockade and inhibition of proteolytic enzyme activity in experimental acute hemorrhagic pancreatitis in mice. Evidence for cholecystokinin as a major factor in the development of acute pancreatitis. 242 40

Using a specific radioimmunoassay for cholecystokinin (CCK) we have studied the relation between circulating CCK concentrations and the feedback regulation of pancreatic enzyme secretion in conscious rats. Recirculation of diverted bile-pancreatic juice into the duodenum or intraduodenal perfusion of trypsin during biliary-pancreatic juice diversion produced basal output of amylase and trypsin and low portal CCK levels (less than 10 pmol/L). Biliary-pancreatic juice diversion or inactivation of trypsin caused increased CCK concentrations (peak values 50-100 pmol/L) and enzyme outputs. During biliary-pancreatic juice diversion, infusion of the CCK receptor antagonist proglumide suppressed the enzyme response without altering the increase in CCK. Measurement of portal and peripheral CCK during biliary-pancreatic juice diversion yielded values of 131 +/- 37 and 32 +/- 5 pmol/L, respectively. The peripheral CCK levels corresponded to concentrations achieved during exogenous CCK-8 infusion which resulted in similar enzyme outputs. Gel chromatography of portal plasma during diversion of biliary-pancreatic juice revealed one peak of CCK corresponding to CCK-8, and a larger peak eluted between CCK-33 and CCK-8, probably representing CCK-22. Similar CCK components were found in water extracts of jejunal mucosa, whereas the acetic acid extracts mainly contained CCK-33/39. We conclude that the negative feedback regulation of pancreatic enzyme secretion in rats is mediated by the release of CCK from the intestine and that the major molecular form of CCK in plasma is probably CCK-22.
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PMID:Role of cholecystokinin in the negative feedback control of pancreatic enzyme secretion in conscious rats. 243 52

The nutritional support of patients with pancreatic and high gastrointestinal fistulas and severe pancreatitis frequently involves intravenous fat infusion. There are conflicting reports on the effect of intravenous fat on pancreatic exocrine secretion. In 10 dogs with chronic pancreatic fistulas, pancreatic juice was collected during secretin (n = 10) or secretin + cholecystokinin (n = 4) stimulation, with and without intravenous fat infusion (5 g/hr). The hormonal-stimulated secretion of lipase, amylase, trypsin, total protein, bicarbonate, and water was unchanged during fat infusion. This study supports the use of intravenous fat as a nutritional source when it is desirable to avoid stimulation of the pancreas.
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PMID:Pancreatic enzyme secretion during intravenous fat infusion. 243 70

The aim of this study was to investigate simultaneously the endogenously stimulated exocrine pancreatic secretion and the cholecystokinin (CCK) response in patients suffering from coeliac sprue. A Lundh-test was performed in nine patients and twenty-six healthy volunteers. Basal plasma-CCK levels (3.4 +/- 0.5 pmol/l in sprue patients vs. 4.1 +/- 0.5 pmol/l in controls) and the integrated 120 min postprandial CCK values showed no differences in both groups. However, in controls the peak CCK value of 27.5 +/- 5.6 pmol/l appeared after 15 minutes whereas in sprue patients the peak of 18.9 +/- 4.5 pmol/l appeared after 60 minutes. CCK concentrations in duodenal biopsies of patients with coeliac sprue revealed significantly lower values compared to controls (123.4 +/- 37.4 versus 240.0 +/- 11.3 pmol/g wet weight). The stimulated lipase output was significantly lower throughout the whole sampling period in coeliac sprue patients whereas amylase output showed an inconstant reduction. The trypsin output was not altered. These results suggest that other mediators than CCK are responsible for the maintenance of trypsin output and for the reduction of lipase output in patients with coeliac sprue.
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PMID:Plasma cholecystokinin and pancreatic enzyme secretion in patients with coeliac sprue. 243 88


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