FIG. 3.
Activation kinetics of NcTOKA whole-cell currents. Currents recorded with SBS containing 10 mM KCl and 10 mM CaCl2. (A) Example of least-square fits of equation 1: I = Iss exp(−t/τ) + C, where Iss is the steady-state current and C is a constant offset. Currents result from voltage pulses ranging from +44 mV to −26 mV in 20-mV steps. The holding voltage was −76 mV. (B) Voltage dependence of the time constants (τ) of activation. Values are the mean (± the SEM) of six independent experiments. (C) Currents recorded from the same cell in response to voltage steps to +44 mV at 1-min intervals from a holding potential (Vhold) of −76 mV. The asterisk denotes the voltage step to −156 mV of 2-s duration ending 1 s prior to the voltage step to +44 mV.