GABA-A R theta: ProductsThe gamma-aminobutyric acid (GABAA) receptor is a multisubunit chloride channel that mediates the fastest inhibitory synaptic transmission in the central nervous system. The GABAA receptors are a major site of action of a number of clinically important drugs. GABAQ is the theta subunit of the GABAA receptor. GABAQ has a unique distribution, with studies so far suggesting significant expression within monoaminergic neurons of both human and monkey brain. Expression of alpha2beta1gamma1theta in transfected mammalian cells leads to the formation of receptors with a 4-fold decrease in the affinity for gamma-aminobutyric acid compared with alpha2beta1gamma1.