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Related to beta receptor: alpha receptor
any one of the postulated adrenergic (sympathetic fibers of autonomic nervous system) components of receptor tissues that respond to epinephrine and such blocking agents as propranolol. 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. Compare alpha receptor.
beta receptorA trio of G protein-coupled cell membrane receptors in the sympathetic nervous system, which dampen the response to catecholamines. They are divided into Beta-1, -2 and -3 receptors.
Beta-1 receptor increases cardiac output by raising the heart rate, impulse conduction, and contraction, thereby increasing the left ventricular ejection fraction; increases juxtaglomerular renin secretion; increases gastric secretion of ghrelin (the hunger hormone, which contrasts to leptin, the satiation hormone).
Beta-2 receptor prompts smooth muscle relaxation resulting in bronchodilation; reduced GI motility; relaxation of detrusor muscle of the bladder; glycogenolysis and gluconeogenesis; and increased renin secretion.
Beta-3 receptor increases lipolysis in fat and thermogenesis in skeletal muscle.