Skip to main content
. 2018 Nov 21;38(47):10180–10201. doi: 10.1523/JNEUROSCI.1049-18.2018

Figure 2.

Figure 2.

Voltage-gated sodium currents from DRG neurons derived from Nav1.7 cKO mice or control littermates. A, TTX-resistant and TTX-sensitive voltage-gated sodium currents were measured from small-, medium-, or large-diameter DRG neurons acutely isolated from either control (cre−) mice or Nav1.7 cKO (cre+) mice. Mice were dissected 7–9 weeks following tamoxifen dosing to ensure complete decay of Nav1.7 protein. Whole-cell voltage clamp was done using a holding voltage of −80 mV, then hyperpolarizing to −120 mV for 20 ms and depolarizing to 0 mV for 20 ms with a stimulus frequency of 1 Hz; 500 nm TTX was used to isolate the TTX-resistant component of the sodium current. B, TTX-sensitive current density measured from small-, medium-, and large-diameter DRG neurons obtained from control (cre−) or Nav1.7 cKO (cre+) mice. TTX-sensitive currents were found to be significantly decreased in small- and medium-diameter Nav1.7 cKO DRG neurons (but not large-diameter) relative to control DRG neurons. C, TTX-sensitive current density versus membrane capacitance as measured on a single-cell basis. D, TTX-resistant current density measured from small-, medium-, and large-diameter DRG neurons obtained from control (cre−) or Nav1.7 cKO (cre+) mice. No significant difference in TTX-resistant currents between DRG neurons from control versus Nav1.7 cKO mice was observed. Most large-diameter neurons did not have detectable TTX-resistant currents. E, TTX-resistant current density versus membrane capacitance as measured on a single-cell basis. ***p < 0.001. Error bars indicate SEM.