Inhibition of gamma-aminobutyric acid uptake: anatomy, physiology and effects against epileptic seizures.

The transport of gamma-aminobutyric (GABA) limits the overspill from the synaptic cleft and serves to maintain a constant extracellular level of GABA. Two transporters, GABA transporter-1 (GAT-1) and GAT-3, are the most likely candidates for regulating GABA transport in the brain. Drugs acting either selectively or nonselectively at GATs exert distinct anticonvulsant effects, presumably because of distinct regions of action. Here I shall give a brief review of the localization and physiology of GATs and describe effects of selective and nonselective inhibitors thereof in different animal models of epilepsy.

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