Synaptically evoked GABA transporter currents in neocortical glia.
The presence, magnitude, and time course of GABA transporter currents were investigated in electrophysiologically characterized neocortical astrocytes in an in vitro slice preparation. On stimulation with a bipolar-tungsten stimulating electrode placed nearby, the majority of cells tested displayed long-lasting GABA transporter currents using both single and repetitive stimulation protocols. Using subtype-specific GABA transporter antagonists, long-lasting GABA transporter currents were identified in neocortical astrocytes that originated from at least two subtypes of GABA transporters: GAT-1 and GAT-2/3. These transporter currents displayed slow rise times and long decay times, contrasting the time course observed for glutamate transporter currents, and are indicative of a long extracellular time course of GABA as well as a role for glial GABA transporters during synaptic transmission.
Kinney
Gregory A
GA
Veterans Affairs Puget Sound Health Care System, Seattle, 98108, USA. gkinney@u.washington.edu
Spain
William J
WJ
D000818:Animals; D001253:Astrocytes / Q000502:physiology*; D002352:Carrier Proteins / Q000502:physiology*; D004553:Electric Conductivity; D050485:GABA Plasma Membrane Transport Proteins; D066298:In Vitro Techniques; D008565:Membrane Proteins / Q000502:physiology*; D026901:Membrane Transport Proteins / Q000502:physiology*; D019579:Neocortex / Q000502:physiology*; D027361:Organic Anion Transporters; D051381:Rats; D013569:Synapses / Q000502:physiology*
D002352:Carrier Proteins; D050485:GABA Plasma Membrane Transport Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D027361:Organic Anion Transporters; C493415:Slc6a1 protein, rat; C092004:Slc6a13 protein, rat