this effect was not significantly modified by adrenalectomy , methysergide , idazoxan ( alpha-2 adrenoceptor antagonist ) , vagotomy alone or plus ligation of carotid arteries or plus atenolol , but was entirely prevented by domperidone or sulpiride pretreatment and was reverted to a pressor response ( due to stimulation of alpha adrenoceptors and 5-hydroxytryptamine receptors ) by blockade of ganglionic transmission with chlorisondamine .
C0001639
alpha-2 adrenoceptor
C0034784
alpha adrenoceptors