Fig. 5.

I_hERG during ventricular action potential voltage-clamp (AP clamp) for WT and L532P hERG (Ai, Aii). Ventricular AP command waveform overlying I_hERG profiles for WT (Ai) and L532P (Aii). In Aii WT current profile is superimposed (in gray) on that for L532P current (black). For each of Ai and Aii, currents are normalized to peak current seen during the waveform (I/I_max). (B, C) Mean normalized plots of instantaneous current–voltage (I–V) relations for I_hERG during AP repolarization for WT (B; n = 7) and L532P (C; n = 8) I_hERG. The arrows indicate the direction of AP repolarization.