Fig. 1

Repeated EA reduced inflammatory pain and regulated microglial activation. A Repeated EA treatment statistically increased the decreased mechanical threshold induced by CFA. Values are represented as mean ± SEM. n = 9 for normal saline group, CFA group, CFA + EA group and CFA + shamEA group. The statistical method is repeated measures ANOVA. *p < 0.05. B Western blot analysis of GRK2 after EA. EA treatment reversed the decline of spinal GRK2 induced by CFA. Results are normalized to GAPDH and shown as ratios to saline-treated mice. Values are represented as mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001. C EA treatments suppressed the expression of Iba1 at the 7th day after the CFA injection. Results are normalized to GAPDH shown as ratios to NS (saline-treated) mice. Values are represented as mean ± SEM. *p < 0.05. The statistical method is one-way ANOVA multiple comparisons. D–F Real-time PCR analysis showed that the mRNA expression of iNOS, TNF-α, IL-1β were up-regulated after the CFA injection and inhibited by EA. G–J Real-time PCR analysis showed that the mRNA expression of CD206, IL-4, IL-10 were remarkably decreased by CFA and up-regulated by EA. Though TGF-β only showed a trend of decline after the CFA injection. Results are normalized to GAPDH mRNA. Values are represented as mean ± SEM. *p < 0.05. The statistical method is one-way ANOVA multiple comparisons