Figure 5.

Effect of 4-AP on spontaneous firing of TMN neurons. A, Effect of 10 mm 4-AP on spontaneous firing of a TMN neuron recorded in cell-attached mode. Pipette contained the same solution as the bath (Tyrode's solution). B, Time course of 4-AP effect on firing (same cell as A). The dashed line corresponds to average firing rate before application of 4-AP. C, Collected data for effects of 10 mm 4-AP on spontaneous firing recorded in cell-attached mode. The solid line shows mean ± SD. D, Effect of 10 mm 4-AP on spontaneous firing recorded in whole-cell mode. The dashed line shows most negative voltage reached during the firing cycle in the control. Note that this shifts in the depolarizing direction with 4-AP. E, Superimposed recordings in D, with spikes aligned at their peaks.