AJP - Gastrointestinal and Liver Physiology, Vol 242, Issue 6 634-G641, Copyright © 1982 by American Physiological Society
Digests of protein augment acid-induced canine pancreatic secretion
A. S. Fink, J. C. Miller, D. W. Jehn and J. H. Meyer
To study interactions between intraluminal acid and protein digests, six
dogs with chronic gastric and pancreatic fistulas received three sets of
intestinal perfusates. The first set contained HCl (1, 2, or 4 mmol/50 ml)
and 64 mM D- or L-phenylalanine. The second set contained HCl plus either
intact or pepsin-digested bovine serum albumin (BSA); the BSA and HCl were
varied so that each 50 ml contained 1, 2, or 4 meq of acid titratable from
an initial pH of 2.0 to an end-point pH of 4.5. The third set was identical
to the second set except for an initial pH of 3.5. All perfusates were
adjusted to 300 mosM and randomly infused at 200 ml/h. L-Phenylalanine
enhanced acid-induced bicarbonate and protein outputs, as did pH 2.0 BSA
digests. At pH 3.5, only acid-induced protein output was augmented by BSA
digests. In additional studies, undigested or digested BSA at pH 7.0 was
infused with secretin (82 pmol.kg-1.h-1). Only digested BSA enhanced
secretin-induced pancreatic secretion. We conclude that there is an
important, albeit complex, interaction between the intestinal acid stimulus
and the protein digest stimulus on pancreatic secretion.
