Pancreatic polypeptide stimulates gastric acid secretion through a
vagal mechanism in rats.
McTigue, Dana M., and Richard C. Rogers.
Department of Physiology, Ohio State University, Columbus, OH
43210
APStracts 2:0157R, 1995.
The present study examined the effect of pancreatic polypeptide (PP)
on gastric acid secretion. A 45 min infusion of PP was delivered into
the jugular vein of urethane anesthetized rats. Rat PP (100 pmol)
significantly increased acid secretion over baseline; bilateral
cervical vagotomy or peripheral atropine both eliminated this acid
response. Neither ip infusion nor close intra-arterial infusion of
100 pmol PP into the gastric circulation altered acid secretion.
These results suggest that although PP requires intact vagal reflexes
to stimulate acid output, it does not act on afferent or presynaptic
efferent terminals of the vagus, or directly within the stomach.
Given that vagal reflexes consist of an afferent limb, an efferent
limb, and a central relay, it may be that the target of circulating
PP lies within the central nervous system. Indeed, previous studies
from our laboratory have shown that microinjection of PP into the
dorsal vagal complex results in long-lasting vagal-dependent
elevation of gastric acid secretion.
Received 7 December 1994; accepted in final form 30 May 1995.
APS Manuscript Number R694-4.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 6 July 1995.