title: Smooth muscle of rabbit aorta contains alpha 1-but not alpha 2-adrenoceptors.
abstract: We have investigated the residual contractile response to noradrenaline remaining after phenoxybenzamine (3 x 10(-7) mol/l) in rabbit aorta, since it has been reported that phenoxybenzamine at low doses completely and irreversibly blocks alpha 1-but not alpha 2-adrenoceptors. The contraction elicited by noradrenaline slowly recovered with time after it had been almost abolished by phenoxybenzamine. This residual response was blocked by the alpha 1-selective antagonist prazosin (3 x 10(-8) mol/l) but not by the alpha 2-selective antagonist rauwolscine (3 x 10(-7) mol/l). The results confirm that the smooth muscle of rabbit aorta contains alpha 2-but not alpha 2-adrenoceptors.
mesh_terms: D000818:Animals; D001011:Aorta / Q000502:physiology*; D004347:Drug Interactions; D005260:Female; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000502:physiology*; D009638:Norepinephrine / Q000494:pharmacology; D010643:Phenoxybenzamine / Q000494:pharmacology; D011224:Prazosin / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D011817:Rabbits; D011941:Receptors, Adrenergic / Q000502:physiology*; D011942:Receptors, Adrenergic, alpha / Q000502:physiology*; D015016:Yohimbine / Q000494:pharmacology
chemical_list: D011941:Receptors, Adrenergic; D011942:Receptors, Adrenergic, alpha; D010643:Phenoxybenzamine; D015016:Yohimbine; D011433:Propranolol; D009638:Norepinephrine; D011224:Prazosin