(A) Traces of evoked action potentials in small-sized neurons of whole-mount DRGs from sham and CCI mice. (B) Frequency of action potentials and effects of CCI, TGF-β1, and SB431542. Note that the CCI-induced increase in action potential frequency was suppressed by TGF-β1 (2 or 10 ng/ml), and this suppression was abrogated by SB431542. *P < 0.05; #P < 0.05, compared with the CCI control. Statistical significance was determined by 1-way ANOVA, followed by Bonferroni’s post-hoc test; n = 5 neurons/group. All data are expressed as the mean ± SEM.