TABLE 1

Activation properties of mutant hERG channels Currents were measured in 135 mM Embedded Image/5 mM Embedded Image.

hERG Channel
Activation
Deactivation
Erev
n
V1/2
k
 τact
 τfast
 τslow
Arelf
mV Ms ms
WT –10.7 ± 1.1 8.4 ± 1.0 898 ± 260 386 ± 38 2002 ± 172 0.37 ± 0.03 –77.8 ± 0.4 6
F656M –11.0 ± 1.2 7.2 ± 0.4 2058.3 ± 203.3 438.4 ± 42.6 2214.0 ± 179.5 0.42 ± 0.03 –76.5 ± 2.5 7
F656T –16.8 ± 3.39* 6.6 ± 0.2 1646.5 ± 369 432.2 ± 16 2434.6 ± 57.7 0.34 ± 0.01 –82 ± 0.2 5
F656V –12.7 ± 1.96 6.0 ± 0.5 1552.1 ± 377 177.3 ± 5.5** 767.6 ± 70.4** 0.69 ± 1.40** –79.7 ± 1.4 4
F656Y –18.15 ± 2.7* 6.1 ± 0.6 1971.3 ± 654.5 228.3 ± 32.6* 1172.0 ± 268.1* 0.55 ± 0.06* –77.8 ± 0.67 5
F656W
–42.35 ± 3.0**
8.2 ± 0.5
375.9 ± 89.4**
597.7 ± 50*
2351.5 ± 322.3
0.54 ± 0.07*
–80.7 ± 1.1
6

  • τact, activation time constant measured at –10 mV; τfast and τslow, fast and slow deactivation time constants measured at –50 mV; Arelf, relative amplitude of the fast component of deactivation measured at –50 mV; Erev, reversal potential.

  • ↵* p < 0.05

  • ↵** p < 0.01