Alpha-1A-adrenoceptor and Alpha-1D-adrenoceptor (α1A-adrenoceptor, α1D-adrenoceptor)

**Alpha-1A-adrenoceptor** and **Alpha-1D-adrenoceptor** are closely related subtypes of the alpha-1 adrenergic receptor family, **G protein-coupled receptors** activated by catecholamines such as norepinephrine and epinephrine[5][4][3]. The α1A is prominent in the prostate, lower urinary tract, and certain vascular and neuronal tissues, mediating smooth muscle contraction involved in urinary tract function and vascular tone[7][4]. The α1D subtype predominates in specific vascular beds such as human epicardial coronary arteries, mediating vasoconstriction and contributing to blood pressure regulation[2][3]. Both subtypes are therapeutic targets for selective α1-blockers, which are used for hypertension and benign prostatic hyperplasia[5][2][4]. Ambiguous combined terms like "alpha-1A/1D adrenoceptor" are sometimes used to describe drugs or tissues where both subtypes are relevant, but for structured data, each should be handled separately as **Alpha-1A-adrenoceptor** and **Alpha-1D-adrenoceptor**[1][3][9]. **Note:** The target as presented, "alpha-1A/1D adrenoceptor," is **ambiguous/incorrect** for a canonical form because it attempts to merge two distinct, though related, subtypes. For structured databases, it is best to resolve to the two standard entities: "Alpha-1A-adrenoceptor" and "Alpha-1D-adrenoceptor."[3][9][1]

Other names

Alpha-1A adrenergic receptorAlpha-1D adrenergic receptorADRA1A (gene for α1A)ADRA1D (gene for α1D)Alpha-1-adrenoceptor (collective term for α1A, α1B, and α1D)Alpha-1C adrenergic receptor (historical for α1A)[3][7]Alpha-1A/D adrenoceptor (historical/ambiguous, used for tissues where both are detected)[1][3][9]Alpha-adrenergic receptor 1a (unclear, sometimes used for α1A)[6]

Antagonism (blockade) of α1A and/or α1D-adrenoceptor to cause smooth muscle relaxation (vasodilation, decreased peripheral resistance, relief of urinary tract obstruction) - Inhibition of vasoconstrictive effects mediated by norepinephrine/epinephrine[5][2][4]