Gamma-aminobutyric acid type A receptor subunit alpha-2 and alpha-3 (GABRA2 and GABRA3)

Gamma-aminobutyric acid type A receptor subunits alpha-2 (GABRA2) and alpha-3 (GABRA3) are integral protein components of the heteropentameric GABA-A receptor, the chief inhibitory neurotransmitter receptor in the adult mammalian central nervous system[1][4][8]. Each subunit consists of four transmembrane regions and is part of a pentameric ligand-gated ion channel that, upon activation by GABA, conducts chloride ions to hyperpolarize the cell membrane, thereby reducing neuronal excitability[1][2]. The arrangement and composition of these subunits confer distinct pharmacological and physiological properties to receptor subtypes, including specific affinity profiles for benzodiazepines and other modulators[7][8]. GABA-A receptors containing alpha-2 or alpha-3 subunits play key roles in mediating the anxiolytic, sedative, anticonvulsant, and muscle relaxant effects of widely used CNS drugs, and dysfunction in their activity is implicated in numerous neurological and psychiatric disorders[4][5][6].

Other names

GABAA receptor subunit alpha-2 (GABRA2)GABAA receptor subunit alpha-3 (GABRA3)Alpha-2 GABA-A receptor subunitAlpha-3 GABA-A receptor subunit

Positive allosteric modulation (benzodiazepines and Z-drugs enhance GABA-induced chloride influx) - Direct agonism (GABA binding triggers opening of the chloride channel) - Negative allosteric modulation (certain agents reduce channel opening) - Antagonism (e.g., flumazenil at the benzodiazepine site)