FIGURE 4.

Voltage dependence of inactivation for macroscopic currents through Ca_V1. 2α₁- and Ca_V1.3α₁-containing channels in the absence and presence of RIM1. Currents were elicited by a 10-s conditioning pulse from a V_h of −80 mV in 10-mV steps from −90 to +40 mV, followed by a test pulse to 0 or −30 mV for Ca_V1.2α₁-containing (A and C) and Ca_V1.3α₁-containing channel currents (B and D), respectively. The individual data points are means of 4–7 experiments. Error bars, S.E. The solid lines reflect fits via a sigmoid equation (the relevant parameters are given in Table 1).