Effect of clozapine-mediated hM4D(Gi) activation on DG evoked potentials. A, Representative EP traces obtained during vehicle (gray) and clozapine (blue) treatment. Multiple population spikes are indicated with arrow. B, fEPSP slope was significantly reduced in the D13 group and DM13 group with titer E + 13 vg/ml, both for the first EP (EPa) and the second EP (EPb) compared with vehicle injection. C, Population spike area/fEPSP slope ratio was significantly reduced in the D13 group and the DM13 group for EPa, and for the D13 group for EPb, compared with vehicle. In some animals from the DM12 and DM11 group with lower titers, population spike/fEPSP slope ratio was strongly increased, although not significantly. D, Paired pulse relationship was increased during clozapine treatment compared with vehicle for all DREADD groups, but effects were only significant in the DM12 group. Dots represent individual animals; *p < 0.05, **p < 0.01, ***p < 0.001. D = DREADD, M = mCherry, DM = DREADD-mCherry, PS = population spike, fEPSP = field EPSP.