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Article Abstract

Anxiety stems from and perpetuates dysregulation of neurobiological systems, but the exactmechanisms of anxiety disorders are still only partially understood. Gamma-aminobutyric acid(GABA) is the primary inhibitory neurotransmitter known to counterbalance the action of the excitatoryneurotransmitter glutamate. Several pharmacologic agents target the GABA system and modulatethe overall effect of GABA. This article highlights multiple neurobiological interactions that play arole in anxiety and reviews selected studies of plasma neurosteroid levels, plasma GABA levels, andbenzodiazepine binding site sensitivity and density in patients with anxiety disorders. The article concludeswith further support for the role of the GABA system in anxiety by summarizing the currentevidence supporting the use of novel GABAergic agents including tiagabine in the treatment of anxietydisorders.