Glycine receptors are ligand-gated chloride channels. Channel opening is triggered by extracellular glycine (PubMed:10188956, PubMed:26344198). Plays an important role in the down-regulation of neuronal excitability. Contributes to the generation of inhibitory postsynaptic currents. Channel activity is potentiated by ethanol (By similarity). Activated by glycine and taurine. Inhibited by strychnine (PubMed:10188956, PubMed:26344198). Allosterically activated by ivermectin (PubMed:26344198). Inhibited by picrotoxinin (PubMed:26344198). Strychnine binding locks the channel in a closed conformation and prevents channel opening in response to extracellular glycine (PubMed:26344198). Can also be activated by GABA and inhibited by bicuculline, but this requires heterologous expression in human cells (PubMed:10188956). Homopentamer (in vitro) (PubMed:26344198). Heteropentamer composed of glra1 and glrb (By similarity). Both homopentamers and heteropentamers form functional ion channels (By similarity). Expressed in brain. The channel pore is formed by pentameric assembly of the second transmembrane domain from all five subunits. Channel opening is effected by an outward rotation of the transmembrane domains that increases the diameter of the pore. Highly sensitive to activation by taurine despite the presence of Val in position 135. In mammals, Val-135 causes a drastic loss of taurine efficacy. The alpha subunit binds strychnine. Belongs to the ligand-gated ion channel (TC 1.A.9) family. Glycine receptor (TC 1.A.9.3) subfamily. GLRA1 sub-subfamily.