[GABA receptor chloride ion channel].

Gamma-Aminobutyric acid(GABA) has been established as a major inhibitory neurotransmitter in the brain. GABAA receptors are coupled to benzodiazepine receptors and barbiturate binding site. They are ligand-gated Cl- channels that consist of a heteromeric mixture of protein subunits forming a pentameric structure. On the other hand, GABAC receptors appear to be relatively simple ligand-gated Cl- channels with a distinctive pharmacology, in that they are not blocked by bicuculline and not modulated by barbiturates, benzodiazepines or neuroactive steroids. Therefore, it is suggested that these multiple GABA receptors generate various inhibitory functions and the pharmacology of these novel subtypes of GABA receptors may yield important therapeutic agents.