Fig. 1.

Effects of femoral artery occlusion on TTX-resistant (TTX-R) and voltage-dependent Na⁺ channel subtype Na_V1.8 (Na_V1.8) currents in rat dorsal root ganglion (DRG) neurons. All rat DRG neurons were dissociated 72 h after femoral occlusion and recorded in voltage patch mode with −80 mV holding followed by a pulse of 20 mV. One micromolar TTX was used to block TTX-sensitive currents, and 500 nM of A803467 was used to block Na_V1.8 currents. A: representative current traces after application of TTX and TTX plus A803467 in DRG neurons of control limb and occluded limb. A greater amplitude of currents was observed in DRG neurons of the occluded limb. B: averaged data showing that femoral artery occlusion amplified current amplitude after TTX application. The data also show that the currents were largely decreased after application of TTX and A803467. Na_V1.8 currents were assessed as $I_{{\text{Na}}_{\text{V}}1.8}$ (peak current after TTX − peak currents after both TTX and A803467). $I_{{\text{Na}}_{\text{V}}1.8}$ was also amplified by femoral artery occlusion. *P < 0.001 between control and occlusion for TTX-R and Na_V1.8 current in DRG neurons. C: femoral artery occlusion also increased current densities in DRG neurons compared with the control group. *P = 0.002 between control and occlusion after TTX; *P < 0.001 between control and occlusion for $I_{{\text{Na}}_{\text{V}}1.8}$. D: %inhibition of $I_{{\text{Na}}_{\text{V}}1.8}$ by A803467 was greater in DRG neurons of occluded limbs than that in DRG neurons of control limbs. *P = 0.010 between control and occlusion. Individual data points are also shown; n = 10 DRG neurons in the control group, and n = 11 in the occlusion group.