Analysis of the role of adrenergic receptors in the regulation of small intestine motor activity in sheep.

In sheep with chronic fistulae of the small intestine and rumen the participation of alpha- and beta-adrenergic receptors in the regulation of the motor activity of the small intestine was studied by the method of pharmacological analysis. The movements of the fistulated parts of the alimentary tract were recorded by the balloon method. Slow intravenous infusion of isoprenaline inhibited the contractions of the small intestine. This inhibitory effect of isoprenaline was abolished by propranolol. Intravenous phenylephrine inhibited the motor activity of this intestinal part as well. The effect of phenylephrine was abolished by pretreatment with dihydroergotamine. In the small intestine of sheep stimulation of the alpha and beta adrenergic receptors decrease the motor activity of intestine.