adrenoceptor Definition

any of a group of receptors on cell surfaces that are activated by epinephrine or norepinephrine : an adrenergic receptor

alpha-receptor

beta-receptor

any of a group of receptors that are present on cell surfaces of some effector organs and tissues innervated by the sympathetic nervous system and that mediate certain physiological responses (as vasodilation, relaxation of bronchial and uterine smooth muscle, and increased heart rate) when bound by specific adrenergic agents —called also beta-adrenergic receptor, beta-adrenoceptor