Fig. 3. Na⁺ currents at different voltages. (A) Pulse protocol of the whole-cell voltage clamp. Step depolarisations from –50 mV to +50 mV in 10 mV steps every 5 s were applied from a holding potential of –70 mV. (B) Whole-cell membrane currents in response to the step depolarisations. Eleven traces are superimposed. The bath solution was N-Ca-free-ASW and the pipette solution was Cs-asp. Cell membrane capacitance (C_m)=124.4 pF.