The effect of zaldaride maleate, an antidiarrheal compound, on acetylcholine-induced intestinal electrolyte secretion

The effect of zaldaride on acetylcholine-induced colonic electrolyte secret ion was examined. The short-circuit current response to acetylcholine was p artially reduced by tetrodotoxin, a neuronal blocker, and was completely in hibited by atropine, an acetylcholine hi receptor antagonist, in the rat co lonic preparations. The tetrodotoxin sensitive effect was significantly inh ibited by zaldaride, whereas the tetrodotoxin insensitive effect was not af fected. Acetylcholine release from synaptosomes of submucosal nerves of gui nea-pig colon was significantly reduced by zaldaride. Zaldaride may reduce colonic electrolyte secretion by acetylcholine due to the inhibition of ace tylcholine release from synaptosomes of colonic submucosal nerves.