Figure 1.

Effects of 100 μM mexiletine on hNav1.4 currents. (A) Time course of sodium current amplitude measured in a representative HEK293 cell permanently transfected with hNav1.4 sodium channel subtype before, during, and after of application of 100 μM mexiletine. The sodium current was elicited by depolarizing the cell membrane to −30 mV for 25 ms every 10 (0.1 Hz) or 0.1 s (10 Hz), from a holding potential of −120 mV. (B) Typical sodium current traces are shown, which were obtained from the average of three records obtained at steady state in absence of drug using 0.1 Hz stimulation frequency (CTRL), and in presence of drug at 0.1 Hz (red) and 10 Hz (blue).