Gastrointestinal effects of metoclopramide in man. In vitro experiments with human smooth muscle preparations.
Metoclopramide (N-(diethylaminoethyl)-2-methoxy-4-amino-5-chlorobenzamide) has been investigated with human gastrointestinal smooth-muscle preparations in vitro. Small-intestinal and colonic circular muscle was contracted by metoclopramide. This effect was antagonized by atropine. Gastric and colonic longitudinal muscle was sensitized by metoclopramide to acetylcholine. Atropine acted here as a partial antagonist of metoclopramide.The interference of acetylcholine and metoclopramide is of a hitherto undescribed pharmacological type. The effects of metoclopramide in vivo-where its action is predominantly on the stomach and pylorus-are not fully explained by these in vitro experiments in which the effect was found to be most pronounced on the colon.
D000109:Acetylcholine / Q000494:pharmacology; D000577:Amides / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D001285:Atropine / Q000494:pharmacology; D003106:Colon / Q000187:drug effects; D004064:Digestive System / Q000187:drug effects*; D004386:Duodenum / Q000187:drug effects; D005765:Gastrointestinal Agents / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D007421:Intestine, Small / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects*; D013270:Stomach / Q000187:drug effects
D000577:Amides; D005765:Gastrointestinal Agents; D001285:Atropine; D000109:Acetylcholine