Figure 6.
Quinidine block of Shaker-IR and P475A. (A) Concentration-dependent inhibition of ionic currents of Shaker-IR by quinidine. Represented traces are the steady-state currents at 0 mV depolarization in presence of different quinidine concentrations. (B) Representative ionic current inhibition for P475A by different concentrations of quinidine. (C) Concentration-effect curve of Shaker-IR (open circles) and P475A (black circles) for quinidine obtained by plotting the normalized Iac currents from pulse protocols shown in panels A and B as a function of quinidine concentration. The solid line represents the fit with the Hill equation. To see this figure in color, go online.