In the central nervous system, two subtypes of sodium- and chloride-coupled GABA transporter exist. One is sensitive to ACHC, the other to β-alanine. They are thought to be of neuronal and glial origin, respectively. GABA transport in membrane vesicles derived from astroglial cells was found to be sodium- and chloride-dependent, electrogenic and much more sensitive to β-alanine than to ACHC. Immunoblotting with antibodies directed against a variety of sequences of the ACHC-sensitive transporter indicated that none of these epitopes was shared by the glial transporter.
