Figure 4: NaV1.9-V1184A channels depolarize DRG neurons.
From: Cold-aggravated pain in humans caused by a hyperactive NaV1.9 channel mutant
Representative single action potentials at 30 °C (a) or 20 °C (b), elicited in murine DRG neurons transfected with wild-type NaV1.9 (black) or mutant NaV1.9-V1184A (red) in response to current injections of 100–200 pA for 5 ms (a) or 10 ms (b). Dotted lines indicate 0 mV; dashed lines mark levels of the RMP. (c) Parameters characterizing action potential properties. Vth: action potential voltage threshold, Vmax: maximum action potential voltage, Vmin: minimum voltage during after-hyperpolarization, width: action potential width at 0 mV, τAHP: single-exponential time constant characterizing the relaxation of the membrane voltage from the action potential after-hyperpolarization (Vmin) back to the resting level. Data points represent mean values with numbers of experimental replicates from four (30 °C) or five (20 °C) animals indicated in parentheses. Error bars in all plots represent SEM. Significance between pairs of data was tested with a two-sided Student’s t-test. ***P<0.001, *P<0.05.
