GABA receptors

The GABA receptors are a class of receptors that respond to the neurotransmitter gamma-aminobutyric acid (GABA), the chief inhibitory compound in the mature vertebrate central nervous system. GABA receptors influence cognition by coordinating with glutamatergic processes. There are two classes of GABA receptors: GABA_A and GABA_B.

GABA_A receptors are ligand-gated ion channels (also known as ionotropic receptors); whereas GABA_B receptors are G protein-coupled receptors, also called metabotropic receptors.

It has long been recognized that the fast response of neurons to GABA that is blocked by bicuculline and picrotoxin is due to direct activation of an anion channel. This channel was subsequently termed the GABA_A receptor. Fast-responding GABA receptors are members of a family of Cys-loop ligand-gated ion channels. Members of this superfamily, which includes nicotinic acetylcholine receptors, GABA_A receptors, glycine and 5-HT₃ receptors, possess a characteristic loop formed by a disulfide bond between two cysteine residues.