EFFECTS OF LOPERAMIDE ON THE GASTRIC AND INTESTINAL MOTILITIES IN THE GUINEA PIG AND DOG

Abstract
In anesthetized dogs, intravenous administration or intrajejunal infusion of Loperamide produced the excitatory effect of gastric, small and large bowel motilities accompanied with elevation of the muscle tone. The excitatory response was slightly suppressed by administration of atropine. Such effects were similar to those of morphine and methadone. In non-anesthetized spinal guinea pigs, Loperamide increased colonic motility accompanied with the augmentation of the colonic muscle tone, but the conduction of the contraction waves was prevented. In anesthetized guinea pigs, intravenous administration of Loperamide reduced the rate of the rhythmic contraction waves of the small intestine, but its effect on the muscle tone was not evident. The activity of Loperamide as an antidiarrheal agent was discussed.