Nature of histaminergic receptors in goat uterus

Abstract

Histamine and 2-pyridylethylamine (2-PEA) caused contraction while dimaprit produced relaxation of isolated goat (Capra hircus) uterine strips. Whereas mepyramine blocked the histamine and 2-PEA-induced contractions, chlorpheniramine reversed the contraction to relaxation, Metiamide potentiated the histamine-induced contraction and blocked the relaxant effect of dimaprit. Caffeine, papaverine and propranolol did not alter dimaprit-induced relaxation, however, unlike caffeine and propranolol, papaverine inhibited the contractile response to histamine. These observations suggest that goat uterus possesses both Hâ‚ excitatory and Hâ‚‚ inhibitory histaminergic receptors.