Effects of Urotensin I on the Isolated Rat Tail Artery

Publisher Website
Google Scholar
Abstract
Urotensin I (UI, a peptide isolated from the urophysis of the white sucker, Catastomus commersoni) elicited dose-related relaxation responses in isolated helical strips of the rat tail artery. The responses were not prevented by adrenergic, cholingergic or histaminergic blocking agents [noradrenaline [norepinephrine], 5-hydroxytryptamine, phenoxybenzamine, phentolamine, acetylcholine chloride, histamine dihydrochloride, mepyramine maleate, metamide, burimamide, KCl, arginine vasopressin, mecamylamine, hexamethonium bromide, propranolol, diphenhydramine]. Competitive and non-competitive components of antagonism were observed to noradrenaline-, 5-hydroxytryptamine- and arginine vasopressin-induced contractions. Atropine caused a direct relaxation of the isolated vascular tissues and a significant potentiation of UI responses.