Journal: Pflugers Archiv : European journal of physiology
Article Title: FHF2 isoforms differentially regulate Nav1.6 mediated resurgent sodium currents in dorsal root ganglion neurons
doi: 10.1007/s00424-016-1911-9
Figure Lengend Snippet: DRG neurons were transfected with Nav1.6r and FHF2A, FHF2B or fluorescent protein tag (control). a, Representative traces of cycle-dependent reduction as a measure of accumulation of long-term inactivation (LTI) for control (black), FHF2A (blue) and FHF2B (purple) groups. b, The percentage of channels available as a function of depolarization cycle shows overexpression of FHF2A (n=19) increased accumulation of long-term relative to control (n=28), whereas, FHF2B (n=13) did not. Activation, inactivation and recovery from inactivation were assayed with a series of standard protocols (see Methods sections). c, Normalized conductance (G/Gmax) as a function of voltage shows that FHF2A (blue squares, n=16) overexpression shifted the voltage dependence of activation relative to control (black circles, n=25). No change is observed for FHF2B overexpression (purple diamonds, n=11) relative to control. d, Normalized current (I/Imax) as a function of voltage shows that voltage dependence of inactivation was shifted to positive potentials in FHF2A (n=19) and FHF2B (n=13) groups relative to control (n=27). e, Fraction of channels available as a function of time shows FHF2A (n=19) overexpression greatly slowed recovery from inactivation relative to control (n=15), whereas, FHF2B (Inset, n=12) enhanced channel recovery. Abbreviations: LTI-Long-term Inactivation; Asterisks (*) represent p <0.0001 obtained from Student’s t-test. Data are mean ± SEM.
Article Snippet: Cell culture DRG neurons were obtained from adult male Sprague Dawley rats.
Techniques: Transfection, Control, Over Expression, Activation Assay