GABA(A) receptor subtypes: dissecting their pharmacological functions

The enhancement of GABA-mediated synaptic transmission underlies the pharma cotherapy of various neurological and psychiatric disorders, GABA(A) recept ors are pluripotent drug targets that display an extraordinary structural h eterogeneity: they are assembled from a repertoire of at least 18 subunits (alpha1-6, beta1-3, gamma1-3, delta,epsilon,theta, rho1-3). However, differ entiating defined GABA, receptor subtypes on the basis of function has had to await recent progress in the genetic dissection of receptor subtypes in vivo. Evidence that the various actions of allosteric modulators of GABA(A) receptors, in particular the benzodiazepines, can be attributed to specifi c GABA(A) receptor subtypes will be discussed, Such discoveries could open up new avenues for drug development.