GABA, an inhibitory neurotransmitter, mediates neuronal inhibition by binding to the GABA receptor and opening an integral chloride channel. Combines with the ligand-gated ion channel subunit GRD to form cation-selective GABA-gated ion channels when coexpressed in Xenopus laevis oocytes. Generally pentameric. There are five types of GABA(A) receptor chains: alpha, beta, gamma, delta, and rho. Interacts with Grd (alpha chain). Belongs to the ligand-gated ion channel (TC 1.A.9) family. Gamma-aminobutyric acid receptor (TC 1.A.9.5) subfamily.