Fig. 11.

Contributions of the major inward currents to small DRG cell action potentials. A, The relative amplitudes of overall charge transferred by each conductance, recorded in the same cell, are plotted against the resting potential of the cell. An anomalous cell expressing purely TTX-S current is obvious (−77 mV resting potential). The latencies of the particular action potentials used for this analysis varied from 1.1 to 11.8 msec in different cells, and there was no significant difference in action potential parameters when action potentials were elicited in the same cell with different latencies in this range. B, Average normalized charge contributions by the TTX-S sodium, TTX-R sodium, and the HVA calcium current are shown for the overall duration of the action potential and separately for current flowing during the upstroke and downstroke. Error bars indicate SD.