Central Alpha2 Adrenergic Receptor (α2-AR)

The central alpha2 adrenergic receptor (α2-AR) is a G protein-coupled receptor (GPCR) primarily associated with the Gi heterotrimeric G-protein. It is activated by endogenous catecholamines such as norepinephrine and epinephrine, playing a crucial role in modulating neurotransmitter release and sympathetic nervous system activity within the central nervous system (CNS). Key subtypes include α2A, α2B, and α2C, each with distinct localization patterns and physiological functions. Therapeutic targeting with selective agonists like clonidine and guanfacine is used for hypertension and anxiety, but side effects such as sedation are common.

Other names

Alpha2 adrenergic receptorα2 adrenergic receptoralpha-2 adrenergic receptorAdrenergic receptor alpha2Central α2-adrenergic receptor

Activation leads to Gi protein coupling, inhibiting adenylyl cyclase, decreasing cAMP levels, reducing calcium influx, hyperpolarizing neurons, and inhibiting neurotransmitter release.