Adrenergic alpha2B receptor (Alpha2B-AR or α2B-AR)

The Adrenergic alpha2B receptor (α2B-AR) is one of three alpha-2 adrenergic receptor subtypes, encoded by the ADRA2B gene. It is a G protein-coupled receptor predominantly expressed in vascular smooth muscle, where it mediates vasoconstrictor (vasopressor) responses to catecholamines. Its activation inhibits adenylyl cyclase, reduces cAMP, hyperpolarizes cell membranes, and leads to reduced neurotransmitter release. α2B-AR is therapeutically relevant in cardiovascular regulation, with drugs targeting this receptor for hypertension, sedation, and analgesia, though most clinically used agents affect all alpha-2 subtypes. Selective targeting of α2B-AR is less common, but the subtype is implicated in the vascular effects of adrenergic agonists and may play roles in disease and drug response.

Other names

Alpha-2B adrenergic receptorα2B-adrenergic receptorADRA2B

Agonists: activate presynaptic α2B-AR, inhibit adenylyl cyclase via Gi protein coupling, leading to reduced cAMP, hyperpolarization, decreased neurotransmitter release, and peripheral vasoconstriction. Antagonists: block receptor and prevent catecholamine-mediated inhibition.