Table 1. Summary of IC₅₀ values and hill coefficients (nH) determined from concentration-response relationships for all studied blockers.

Name	WT		Y652A-hERG			F557L-hERG
	IC50 (μM)	nH	IC50(μM)/% block @100 μM	nH	∆IC50	IC50(μM)/% block @100 μM	nH	∆IC50
Dofetilide	2.5 ± 0.2 n = 4	1.3 ± 0.2	23% n = 5	0.6 ± 0.2	>50	31% n = 7	0.5 ± 0.4	>50
Terfenadine	1.1 ± 0.04 n = 6	2 ± 0.2	9.3 ± 2.3 n = 4	1.03 ± 0.2	8.4	12.8 ± 2.3 n = 8	1.3 ± 0.1	11.6
Astemizole	0.25 ± 0.02 n = 6	1.1 ± 0.1	4.4 ± 0.3 n = 5	0.9 ± 0.1	17.6	1.6 ± 0.2 n = 6	1.1 ± 0.1	6.4
Cisapride	1.1 ± 0.1 n = 5	0.9 ± 0.03	81.4 ± 8.1 n = 4	1.03 ± 0.1	74	10.1 ± 0.6 n = 7	0.7 ± 0.03	9.2
Haloperidol	1.3 ± 0.1 n = 4	1.3 ± 0.1	40.1 ± 1.9 n = 4	1 ± 0.04	31.4	30.3 ± 7.5 n = 4	1.7 ± 0.3	23.3
Amiodarone	2.7 ± 0.3 n = 5	2.1 ± 0.4	13.5 ± 1.05 n = 5	2.3 ± 0.2	5	9.02 ± 1.05 n = 5	3.1 ± 0.2	3.34

(n = number of experiments).