Brain
There are dozens of other chemical neurotransmitters that are used in more limited areas of the brain, often areas dedicated to a particular function. Serotonin, for example—the primary target of antidepressant drugs and many dietary aids—comes exclusively from a small brainstem area called the raphe nuclei. Norepinephrine, which is involved in arousal, comes exclusively from a nearby small area called the locus coeruleus. Other neurotransmitters such as acetylcholine and dopamine have multiple sources in the brain, but are not as ubiquitously distributed as glutamate and GABA.
GABA transporter
GABA transporter group consists of six different transporters:GAT1 and GAT3 are the major GABA transporters in the brain and spinal cord, expressed by both neurons and some astrocytes. GAT2 and BGT1 are also expressed in the brain, but at low levels and mostly in the meninges. GAT2 also transports taurine, while BGT1 transports betaine. These two transporters are predominantly expressed in the liver, but are also found in the kidneys and, as mentioned above, in the meninges.