Figure 3.

(A) Representative currents obtained from a cell expressing both the ShC/B channels and MsrA in response to a double-pulse protocol to measure recovery from inactivation. Two 1.5-s pulses to +30 mV separated by the variable intervals were given every 25 s. The interpulse voltage was −100 mV. (B) MsrA coexpression slows the time course of recovery from inactivation and reduces its variability. The left plot shows the recovery curves from four cells expressing ShC/B only, and the right plot shows the recovery curves from three cells expressing both ShC/B and MsrA. The fractional recovery is defined as the ratio of the peak current during the second pulse over that during the first pulse. The channels were expressed in Xenopus oocytes and the whole-oocyte currents were recorded as in A.