R1629Q alters Nav1.5 channel inactivation kinetics and prolongs the recovery time from inactivation.
(A) Voltage dependence of steady-state activation and inactivation curve of WT (open circle) and R1629Q (filled square) channels. The protocol was shown in the Inset and Values for the half-maximal voltage (V1/2) were provided in the table 1. (B) Time courses of recovery from inactivation were investigated using the two-pulse protocol show in the inset. Time constants are as follows: WT, τf=3.2±0.2ms, τs=104.1±20.0ms,n=11;R1629Q,τf=22.5±1.0ms,τs=139.0±14.0ms,n=12.(Comparison of τf between groups is statistically significant. P<0.01).Results are presented as mean±SE.