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Biomedical subjects

J Christophe

Publications and source records attributed to J Christophe.

At least 289 records · Page 16Linked to original sources

Pancreatic secretion of total protein and of three hydrolases collected in healthy subjects via duodenoscopic cannulation. Effects of secretin, pancreozymin, and caerulein.

Pancreatic secretion of total protein and of three types of hydrolases (amylase, lipase, and thymotrypsinogen(s) was determined in human subjects free of gastrointestinal disease. Pure pancreatic juice was collected by canulation of Wirsung's duct under duodenoscopy. Rapid intravenous injection of pancreozymin (1 Crick-Harper-Raper U per kg) stimulated secretion of total protein and hydrolases within 1 min. This stimulation was of short duration and had a half-life of 70 to 100 sec. Rapid intravenous injection of caerulein (20) ng per kg) induced a similar response. Parallel variations in total protein, amylase, lipase, and chymotrypsinogen(s) were observed in the three experiments where complete enzyme analyses were performed.

Adult↗

In vitro interactions of gastrointestinal hormones on cyclic adenosine 3':5'-monophosphate levels and amylase output in the rat pancreas.

Four-fold increases in cyclic AMP levels were observed 5 to 10 min after rat pancreatic fragments were incubated with 10-7 M secretin or 10-6 M vasoactive intestinal polypeptide (VIP), in addition to 10 mM theophylline. From dose-response curves it appears that, on a molar basis, the potency of secretin was 20 times higher than that of VIP. It is concluded that cyclic AMP is probably the intracellular messenger of both secretin and VIP in centroacinar cells. Pancreozymin, caerulein, and the C-terminal octapeptide of pancreozymin inhibited the production of cyclic AMP observed with secretin of VIP, suggesting that the first three peptides were acting at a binding site different from the agonists, but coupled with the same adenylate cyclase. In acinar cells, secretin was able to exert slight ecbolic effects, and was also able to potentiate the effect of maximal concentrations of pancreozymin, caerulein, or the C-terminal octapeptide of pancreozymin. There was no simple correlation between amylase output and cyclic AMP levels, and copious amylase secretion was elicited even at control levels of cyclic AMP. Glucagon was neither an agonist nor an antagonist of any of the other polypeptides tested.

Amylases↗