[5][6] GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABAA receptors, which are ligand-gated chloride channels.

Chloride conductance of these channels can be modulated by agents such as benzodiazepines that bind to the GABAA receptor.

[5] Recent research has produced several ligands which are moderately selective for GABAA receptors containing the α5 subunit.

Inverse agonists at this subunit have nootropic effects and may be useful for the treatment of cognitive disorders such as Alzheimer's disease.

This article incorporates text from the United States National Library of Medicine, which is in the public domain.