Figure 4.

Activation rate was measured using an envelope of tails protocol. V_m was depolarized from the holding potential of −90 mV to the test potential for durations between 20 and 500 ms in 60 ms increments. The membrane potential was then returned to −40 mV, which elicited an outward tail current, the peak of which indicates the degree of activation. Traces are shown for activation to −10 and +80 mV for all models (A–E). (E) The CR model has a large transient current flux immediately after depolarization to +80 mV, which is shown in detail (inset). (F) Voltage protocol.