Beta-adrenoceptor and Alpha1-adrenoceptor (β1-AR and α1-AR)

Beta-adrenergic receptor and Alpha-1 adrenergic receptor are subclasses of adrenergic receptors—G protein-coupled receptors that mediate the physiological effects of the catecholamines norepinephrine and epinephrine. Beta-1 adrenergic receptors are primarily expressed in the heart and kidneys and are key regulators of heart rate, myocardial contractility, and renin release. Alpha-1 adrenergic receptors, found mostly on smooth muscle of blood vessels and organs, drive vasoconstriction and blood pressure regulation, and also participate in other smooth muscle contractions throughout the body. Both receptor families are major drug targets in cardiovascular, neurological, and certain metabolic diseases, with well-established agonists and antagonists used therapeutically.

Other names

Beta-adrenergic receptorβ-adrenergic receptorbeta-adrenoceptorbeta-ARBeta-1 adrenergic receptorβ1-adrenoceptorAlpha-1 adrenergic receptorα1-adrenoceptoralpha-1 ARAdrenergic receptorAdrenoceptor

β1-AR: Agonists: Increase heart rate, contractility, conduction velocity via Gs and cAMP signaling. Antagonists: Decrease heart rate, blood pressure; block catecholamine effects (used in hypertension, arrhythmia, etc.). α1-AR: Agonists: Vasoconstriction by activating Gq, IP₃/DAG pathway, increasing intracellular calcium. Antagonists: Vasodilation, reduced blood pressure; relax smooth muscle in bladder/prostate.