FIGURE 7.

Kinetic analysis of the development of inactivation under symmetrical (K_out/K_in) and bi-ionic conditions (K_out/Rb_in). (A–C) Voltage-dependence of the time constants derived from the best-fit biexponential functions that described the development of macroscopic inactivation for Kv4.1, Kv4.2, and Kv4.3 channels. Ionic conditions were as described in Fig. 6 legend (black symbols, K_out/K_in; red symbols, K_out/Rb_in). Both ionic conditions were paired from the same patch. The line is the best-fit exponential that describes the voltage-dependence of the time constants derived from the development of inactivation of the Rb⁺ currents (Materials and Methods). (D–F) Voltage-dependence of the corresponding amplitude ratio A_F/A_S derived from the biexponential fits. Symbols are the means from three to seven experiments.