Comparative analysis of the vagal stimulation of gastric acid secretion in rodent isolated stomach preparations

Abstract

Electrical field stimulation produced a tetrodotoxin‐sensitive, frequency‐dependent, release of acid from isolated, lumen‐perfused, stomach preparations from mouse, immature rat and guinea‐pig. In the guinea‐pig and mouse preparations, the frequency‐dependent response was abolished by hexamethonium, acetylcholine (ACh) muscarinic (M) and histamine H2‐receptor blockade, consistent with the hypothesis that the vagal ACh acts indirectly by stimulating the release of endogenous histamine. In contrast, in the rat preparation the frequency‐dependent response was partially refractory to all of these inhibitors. However, a combination of H2‐ and ACh M‐receptor blockade did abolish the effect. We conclude that vagal‐stimulated acid secretion in the rat, unlike the other two species, behaves as though there is a direct innervation of the oxyntic cells by either cholinergic or noncholinergic neurones. 1994 British Pharmacological Society