Relaxation of isolated rabbit veins mediated by latent histamine H2-receptors.
Isolated rabbit veins preconstricted by either norepinephrine, methoxamine or potassium were relaxed by histamine in the presence of mepyramine, a histamine H1-antagonist. The relaxation was not antagonized by atropine, propranolol and indomethacin but by an H2-antagonist cimetidine. It is likely that histamine relaxes the rabbit veins through H2-receptors.
D000818:Animals; D002927:Cimetidine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006632:Histamine / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009126:Muscle Relaxation / Q000187:drug effects*; D009131:Muscle, Smooth, Vascular / Q000502:physiology*; D011738:Pyrilamine / Q000494:pharmacology; D011817:Rabbits; D011968:Receptors, Histamine / Q000502:physiology*; D011970:Receptors, Histamine H2 / Q000502:physiology*; D014680:Veins / Q000502:physiology
D011968:Receptors, Histamine; D011970:Receptors, Histamine H2; D002927:Cimetidine; D006632:Histamine; D011738:Pyrilamine