Figure 9.

BQCA increases the firing rate of mPFC neurons in vivo in rats. Multiple single-unit recordings were obtained from the medial prefrontal cortex of conscious, freely moving rats. A total of 57 cells (vehicle, n = 20, BQCA, n = 37) with waveform and firing rate characteristics consistent with those of putative pyramidal cells were obtained from 6 rats in the presence of either vehicle or drug (20 mg/kg). The mean firing rate for each neuron within an epoch was calculated as described in Materials and Methods and expressed as a percentage of the preinjection baseline rate. a, Treatment with BQCA (■) resulted in an elevation in spontaneous firing rate that was significantly different from vehicle (▴) (2-way ANOVA; BQCA vs vehicle; p < 0.005) within the first 30 min epoch and was maintained across the entire trial period. b, Unit recordings were highly stable over the course of the recordings as illustrated by action potential traces recorded during baseline (solid black trace) and at the end (60–90 min) of the postdrug recording period (dashed gray trace). c, Normalized peak spike amplitude over the course of the experiment; each point is a spike, and the gap in recording corresponds to time of BQCA or vehicle injection.