Figure 7. Reversible antagonism of the dopaminergic effects by haloperidol.

A, a chart record of the IC granule cell membrane current at a maintained holding potential of -80 mV, with periodic superimposed test voltage-clamp commands imposed at the indicated recording times (in minutes) after achieving the whole-cell recording configuration. The experiment commenced with 10 μm haloperidol in the ACSF bathing the slice and the antagonist was withdrawn after 30 min of recording; 500 nm quinpirole was applied in the presence of haloperidol (dark bar) and, following washout of the haloperidol, was reapplied at 100 nm (open bar). B, currents driven by 25 mV hyperpolarizing steps (averages of 12) acquired at times during the experiment as indicated in A. The traces labelled quinpirole indicate responses recorded following exposure to 8 min or 5 min of one of the two concentrations of quinpirole. The ACSF also contained 0.5 μm TTX and 1 mm Ba²⁺.