Figure 3
Mutation A735V shifts the activation curve of NaV1.5 channels in hiPSC-CMs. (a,b) Voltage protocol for sodium channel activation and representative current traces of cardiac NaV1.5 channels recorded from WT hiPSC-CMs (a) and mutant A735V hiPSC-CMs (b). (c) Voltage dependence of mean NaV1.5 current densities (pA/pF) from WT and mutant A735V hiPSC-CMs. Inset: Comparison of the maximum NaV1.5 current density from WT and mutant A735V hiPSC-CMs. (d,e) Voltage protocol for sodium channel inactivation and representative current traces of cardiac NaV1.5 channels recorded from WT hiPSC-CMs (d) and mutant A735V hiPSC-CMs (e). (f) Sodium channel activation (G/Gmax) and inactivation (I/Imax) curves of NaV1.5 channels from WT and A735V hiPSC-CMs. Solid lines represent Boltzmann functions that were fit to the mean values. (g,h) Scatter plots and mean values (±s.e.m.) of mid voltages (V0.5) of activation (g) and inactivation (h) for WT and A735V-NaV1.5 channels from hiPSC-CMs. - Data volume for sodium channel activation: WT, n = 20; A735V, n = 57; for sodium channel inactivation: WT, n = 17; A735V, n = 56.
