Concentration-dependent block of hERG channels by dofetilide.
hERG channels are expressed in HEK cells. Example of an original current trace obtained by manual patch clamp is shown in A. Cells are depolarized from -80 mV to +20 mV for 4 seconds and stepped back to -50 mV for 6 sec. In this example, the cell was exposed to 10 and 30 nM dofetilide. B: Concentration-response curve for reduction of hERG tail current by dofetilide. Data are shown as mean ± SEM (n=3-6) and are in agreement with the literature (IC50= 12 nM in HEK cells; Snyders & Chaudhary, Mol Pharmacol. 1996; 49 (6): 949-55.)