Prejunctional muscarinic (M₁)‐receptor interactions on guinea‐pig ileum: lack of effect of cisapride

Abstract

the effects of McN-A-343 and pirenzepine on the electrically stimulated guinea-pig ileum are compatible with an interaction on presynaptic muscarinic-(M1)-receptors. Cisapride enhances the twitch amplitude via mechanisms independent of such M1-receptor interactions.