AJP - Gastrointestinal and Liver Physiology, Vol 271, Issue 3 501-G508, Copyright © 1996 by American Physiological Society

ARTICLES

CK-independent increases in pancreatic secretion induced by dietary protein in chronic BPJ-diverted rats

H. Hara, T. Nishi, H. Narakino and T. Kasai
Department of Bioscience and Chemistry, Faculty of Agriculture, Hokkaido University, Sapporo, Japan.

Previously, we demonstrated that, in rats with chronic bile-pancreatic juice (BPJ) diversion, pancreatic enzyme secretion was increased after feeding animals a 25% casein fat-free diet. We determined whether cholecystokinin (CCK) or the cholinergic pathway is associated with the response of pancreatic secretion after protein ingestion in the diverted rats, using a potent CCK antagonist, MK-329 or FK-480, and a cholinergic blocker, atropine. Secretion rates of chymotrypsin and trypsin in the fasting state were very high 7 days after a BPJ diversion, and the hypersecretion of the proteases was markedly reduced with an injection of MK-329, FK-480, or atropine and was further reduced by combined injection of FK-480 and atropine. The lowered secretion of the proteases in CCK-antagonized rats was increased after oral feeding of a protein diet and after a duodenal instillation of some protein sources, especially hydrolysate of guanidinated casein (HGC). The CCK-independent increases by HGC instillation are completely depressed by atropine. In rats treated with only atropine, the lowered secretion tended to be increased by a duodenal instillation of HGC. Increases in secretion after an administration of the protein source in CCK-antagonized rats were not affected by bestatin, an inhibitor of brush-border peptidases. We conclude that the stimulatory effects of dietary protein on the pancreatic enzyme secretion partially do not depend on CCK in chronic BPJ-diverted rats and that the CCK-independent increase is atropine sensitive.

This article has been cited by other articles:

				T. Nishi, H. Hara, T. Hira, and F. Tomita Dietary Protein Peptic Hydrolysates Stimulate Cholecystokinin Release via Direct Sensing by Rat Intestinal Mucosal Cells Experimental Biology and Medicine, December 1, 2001; 226(11): 1031 - 1036. [Abstract] [Full Text] [PDF]

				H. Hara, C. Sauchi, T. Nishi, and T. Kasai Intestinal Fat Suppresses Protein-Induced Exocrine Pancreatic Secretion in Chronically Bile-Pancreatic Juice-Diverted Rats Experimental Biology and Medicine, March 1, 2000; 223(3): 276 - 281. [Abstract] [Full Text]