Figure 6. The S1–S6 chimaera is inhibited by dofetilide, the classical hERG pore blocker.

(a) A three step voltage protocol used to determine inhibition by dofetilide. (b–c) Representative current traces for hERG (b) and the S1–S6 chimaera (c) before (black trace) and during (light gray trace) application of 10 μM dofetilide and after washout of the drug (dark gray). (d) Dofetilide concentration-response relationship for hERG and the S1–S6 chimaera. IC₅₀ value for inhibition by dofetilide for the S1–S6 chimaera (39.54 ± 8.68 nM) was not significantly different from that for hERG (19.32 ± 9.6 nM) (p > 0.05; n = 4).