| a site on a cell, as of the heart, that, upon interaction with epinephrine or norepinephrine, controls heartbeat and heart contractability, vasodilation, smooth muscle inhibition, and other physiological processes. |
| beta-adrenergic receptor n. See beta-receptor. |
be·ta-re·cep·tor  (bā'tə-rĭ-sěp'tər, bē'-)  n. A site in the autonomic nervous system in which inhibitory responses occur when adrenergic agents, such as norepinephrine and epinephrine, are released. Activation of beta-receptors causes various physiological reactions, such as relaxation of the bronchial muscles and an increase in the rate and force of cardiac contraction. Also called beta-adrenergic receptor. |
beta-adrenergic receptor n.
Any of various cell membrane receptors that can bind with epinephrine and related substances that activate or block the actions of cells containing such receptors. These cells initiate physiological responses such as increasing the rate and force of contraction of the heart as well as relaxing bronchial and vascular smooth muscle. Also called beta-receptor.