The excitability of IB4+ nociceptors is enhanced after knockdown of Kv4.3, KChIP1, or DPP10. FAM-tagged ASO for LacZ, Kv4.3, KChIP1, or DPP10 was intrathecally injected into the rat by lumbar puncture, and the bilateral L4–L6 DRGs were isolated 5 h later. DRG neurons were dissociated and cultured for 20–24 h before whole-cell patch-clamp recording. A, Top, Only small DRG neurons (soma diameter ≤ 30 μm; bright-field, BF) with both FAM (green) and Alexa594-conjugated IB4 (red) signals were analyzed. Scale bar, 20 μm. Bottom, Responses to the depolarizing current pulses (100 and 300 pA; 1 s). B, The resting membrane potential (Vrest) in each ASO group. n = 9–12 as indicated in D. *p < 0.05 (Tukey's post hoc test after one-way ANOVA). **p < 0.01 (Tukey's post hoc test after one-way ANOVA). C, The rheobase of each ASO group. *p < 0.05 (Tukey's post hoc test after one-way ANOVA). D, Plot of spike number versus injected current pulse. *p < 0.05, Kv4.3 ASO versus LacZ ASO. #p < 0.05, KChIP1 ASO versus LacZ ASO. ##p < 0.01, KChIP1 ASO versus LacZ ASO. Δp < 0.05, DPP10 ASO versus LacZ ASO (Tukey's post hoc test after one-way ANOVA).