Fig. 3.
Dopamine-induced suppression of pp fEPSP slope does not depend on GABAA inhibition and involves both NMDA and AMPA components of the response. A, Blockade of GABAA inhibition by picrotoxin (n = 6) did not affect the magnitude of dopamine-induced suppression but increased the pp fEPSP slope during washout. B, Dopamine strongly suppressed the isolated AMPA fEPSP slope in the pp but not in the sc. C, Isolated NMDA component of the fEPSP in both the pp and the sc show strong inhibition by dopamine. Time of drug applications is marked by rectangles. Experiments inB and C were done in 0.1 Mg2+ in the presence of picrotoxin; tetrodotoxin was not used.