Four transporters mediate GABA uptake in the brain, GAT1-3 and BGT1. They terminates the action of GABA by high affinity sodium-dependent reuptake into presynaptic terminals. Transport of GABA by GAT1-3 is proposed to be accompanied by 2Na+ ions and 1 Cl- ion (Loo DD et al, 2000).
SLC6A1 encodes a sodium- and chloride-dependent GABA transporter 1, GAT1, which is the predominant GABA transporter in brain. It is widely distributed in the brain and co-localized to GABAergic neurons (Nelson H et al, 1990). SLC6A13 encodes a sodium- and chloride-dependent GABA transporter 2, GAT2, which is localized to GABAergic neurons in the brain. It is also found in retina, liver and kidney (Christiansen B et al, 2007). SLC6A11 encodes a sodium- and chloride-dependent GABA transporter 3, GAT3. It is expressed in the brain and localizes to GABAergic neurons (Borden LA et al, 1994).