Figure 6

ATX-II prolongs slow time constant of inactivation of Nav1.7 and Nav1.6. (a) Voltage-dependence of activation and steady-state fast inactivation of heterologously expressed Nav1.7 (left, control n = 8, ATX-II n = 22) and Nav1.6 (right, n = 17), both recorded with the beta4 peptide in the pipette. For results of Boltzmann-fits see text. (b) and (c): Results from a double exponential fit to current decay of traces evoked by the activation protocol from cells expressing Nav1.7 (left, n = 4-22) or Nav1.6 (right, n = 7–17). (b) Fractional A1 (A1/(A1 + A2)) is shown as a function of voltage. (c) Fast and slow time constants τ of current decay are shown as a function of voltage. In both channel subtypes (Nav1.7 left column, Nav1.6 right column) only slow time constants (circles) are significantly prolonged, whereas fast time constants (squares) are unaffected by ATX-II. Independent-sample T-test for Nav1.7, paired-sample T-test for Nav1.6, * p < 0.05, ** p < 0.01, *** p < 0.001.