Genetic manipulations of GABA_A receptor in mice make inhibition exciting

The inhibitory neurotransmitter γ-aminobutyric acid (GABA) plays an important role in brain development and behavior. GABA_A receptor subunits knock-out and knock-in mice have proven that GABA_A receptors are involved in control of motor coordination, learning, and memory and play a role in anxiety, panic, and epileptogenesis. In addition, these receptors are involved in the molecular mechanisms of action of many drugs and participate actively in cortical plasticity. The use of genetically engineered mice has perhaps never been as successful as in understanding the importance of the heterogeneity of GABA_A receptors. We review these findings and speculate on the new directions that the use of mice with altered expression of GABA_A receptor subunits may provide.