Stimulation-rate dependence of Y1795C channel sustained current (I_sus): agreement between simulated and experimental data. (a) The panels compare experimental (left) and simulated (right) records of Y1795C channel sustained current (I_sus) during trains (20 pulses) of repetitive voltage pulses applied after a pulse-free period. Shown is the superposition of current in response to the first and 20th pulses (–10 mV, 500 milliseconds). The experimental records are TTX-sensitive currents (see Methods). The interpulse interval was 20 milliseconds. (b) Pulse-dependent changes in I_sus during rapid stimulation. I_sus during successive pulses (I_susn) was normalized to I_sus recorded (left) or computed (right) during the first pulse (I_sus1) of the pulse train and plotted versus pulse number. The interpulse interval was 20 milliseconds. (c) Pulse-dependent changes in I_sus in response to slow stimulation rate. I_sus was measured, computed, and plotted as in b, but in this case the interpulse interval was 1 second. CL, cycle length.