AMPHETAMINE LOWERS EXTRACELLULAR GABA CONCENTRATION IN THE VENTRAL PALLIDUM

In vivo dialysis was performed in the ventral pallidum of the conscious rat, and extracellular levels of γ-aminobutyric acid (GABA) measured. Forty minutes following peripheral administration of amphetamine (2.0 mg/kg, s.c.) the extracellular concentration of GABA was significantly reduced, in parallel with a significant elevation in motor activity. These data indicate that a decline in GABA transmission in the ventral pallidum may be important in the initiation of amphetamine-induced motor activity. © 1990.