Figure 6From: Dexmedetomidine inhibits Tetrodotoxin-resistant Nav1.8 sodium channel activity through Gi/o-dependent pathway in rat dorsal root ganglion neurons Effect of DEX on the action potential threshold and firing rate of DRG neurons. (A) In current clamp model, depolarizing current pulse required to evoke an action potential in a DRG neuron before and after application of DEX (a = 25 pA, b = 30 pA, c = 40 pA, d = 45 pA). (B) DEX (3 μM) reduced the amount of currents required to evoke action potential. (C, D) Firing response of DRG neurons to a 200 pA depolarizing current pulse (500 ms) before and after application of DEX (C) and selective α2A-AR agonist guanfacine (D). (E) Summary data indicate the inhibitory effects of DEX and guanfacine on firing rate in DRG neurons. (F, G) Current clamp recording showing suppression of capsaicin-induced action potential firing by DEX (3 μM). *p < 0.05; **p < 0.01.Back to article page