As mentioned above, not many studies have been performed investigating receptors containing any one of the minor GABAA receptors subunits (γ1, γ3, θ, ε, π). These subunits have been demonstrated to have a distinct regional distribution, in some cases, co-precipitation with other GABAA receptor subunits has been demonstrated, and recombinant receptors have been generated exhibiting specific properties (for review see Sieghart and Sperk, 2002). But the lack of a selective pharmacology and function in the brain indicated that receptors possibly formed from these subunits at present are quite tentative, justifying their inclusion into the list of “tentative receptors”.
