Role of vagus nerves and gastrin in the gastric phase of acid secretion in male anesthetized rats. Noto, Tsunehisa, Masaaki Nagasaki, and Toshio Endo. Lead Optimization Research Laboratory, Tanabe Seiyaku Co., Ltd., Toda, Saitama 335, Japan
APStracts 3:0213G, 1996.
We determined the role of vagus nerves and gastrin on the acid secretion induced by mechanical and chemical stimulation of gastric lumen in male anesthetized rats using pylorus ligation model. Gastric distension induced by intragastric instillation of saline stimulated the acid secretion to 17-fold over the basal level without an alteration of serum gastrin levels. The distension-stimulated acid secretion was inhibited by bilateral subdiaphragmatic vagotomy but not by CI-988, a gastrin receptor antagonist. Intragastric peptone stimulated the acid secretion to 71-fold over the basal level which was accompanied by a significant increase in serum gastrin levels. While vagotomy almost abolished, CI-988 inhibited the peptone -stimulated acid secretion by only 50 %. We conclude that the vagus nerves mediate the acid secretion by both mechanical and chemical stimulation and that gastrin mediates partly the acid secretion by chemical stimulation but not by mechanical stimulation in male anesthetized rats.

Received 8 October 1996; accepted in final form 18 September
1996.
APS Manuscript Number G87-6.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 5 November 1996