Gamma-aminobutyric acid type A receptor alpha 3, alpha 5, and alpha 6 subunits (GABA_A receptor α3/α5/α6)

The Gamma-aminobutyric acid type A (GABA_A) receptor is a pentameric ligand-gated chloride channel that serves as the primary mediator of rapid inhibitory neurotransmission in the mammalian central nervous system (UniProt P34903, P31644, P47870). The α3, α5, and α6 subunits are distinct protein components that assemble with other subunits (typically β and γ) to form functional receptor subtypes with unique physiological roles and pharmacological sensitivities. The α3 subunit is prominently expressed in the thalamus and spinal cord, where it contributes to sensorimotor gating and the modulation of nociceptive signaling (PubMed: 25324467). The α5 subunit is primarily localized to the hippocampus and cortex, mediating tonic inhibition that is critical for regulating synaptic plasticity, learning, and memory (PubMed: 15630489). The α6 subunit is almost exclusively found in the cerebellum and is involved in motor coordination and sensory processing (PubMed: 10601450). Therapeutic interest in these subtypes focuses on developing selective allosteric modulators to treat anxiety, cognitive deficits in schizophrenia or Alzheimer's disease, and chronic pain, while minimizing the sedation and ataxia associated with non-selective α1-containing receptor activation.

Other names

GABRA3GABRA5GABRA6GABA(A) receptor subunits alpha-3, alpha-5, and alpha-6

Positive allosteric modulation (PAM) or negative allosteric modulation (NAM) at the benzodiazepine binding site or other allosteric sites to regulate chloride channel opening frequency and duration (IUPHAR/BPS Guide to Pharmacology).