TABLE 1

Steady-state activation (m∞) and inactivation (h∞) and the effects of mexiletine on the recovery from inactivation of WT Na_v1.4 and W1531C channels

Recovery data were fit with a biexponential function (see Materials and Methods). Data represent the mean ± S.E.M. of three to five oocytes.

Channel	V_1/2^m∞	V_1/2^h∞	Control			100 μM Mexiletine			300 μM Mexiletine
Channel	V_1/2^m∞	V_1/2^h∞	τ_fast	τ_slow	A_slow	τ_fast	τ_slow	A_slow	τ_fast	τ_slow	A_slow
Na_v1.4	-33.7 ± 2.6	-48.6 ± 0.5	1.1 ± 0.0	43.1 ± 4.7	5.6 ± 0.7	2.0 ± 0.3*	447.6 ± 72.0*	35.2 ± 6.0*	4.2 ± 0.2*	724.0 ± 51.0*	78.0 ± 5.4*
W1531C	-28.8 ± 0.7	-70.0 ± 1.6^†	2.3 ± 0.6	105.2 ± 38.3^†	31.2 ± 8.6^†	5.7 ± 1.6	151.5 ± 56.8^†	30.3 ± 5.1^†	12.7 ± 0.3*^†	156.1 ± 24.8^†	40.0 ± 8.5^†

↵* Statistical significance (p < 0.05) with respect to control values of the corresponding channels.
↵† Statistical significance (p < 0.05) from WT values.