Figure 2.
Activation of dopamine D2-receptors with quinpirole slows evoked DA overflow and converts hybrid responses to slow-type responses. A) Before quinpirole, evoked release begins without delay after the onset of stimulation (60 Hz). Quinpirole delays the onset of evoked release and diminishes the amplitude of release evoked by the first 12 stim pulses (solid diamonds). B) Quinpirole abolishes 12-pulse stim responses. C) The decrease in DA release evoked by 12 stim pulses after quinpirole is significant (ANOVA: F(1,3) = 100.8; n = 3; p<0.001).