Effects of electroacupuncture at Yanglingquan （GB 34） and Huantiao （GB 30） acupoints with different frequencies on pain behaviors and analgesic mechanisms in rats with neuropathic pain

Key Points

• This study aims to investigate the effects of electroacupuncture at specific acupoints on pain behaviors and associated protein levels in a neuropathic pain rat model.
• 54 SD rats were randomly assigned to groups: normal, model, placebo, and three electroacupuncture frequency groups (2Hz, 50Hz, 100Hz), with 9 rats per group.
• Chronic constriction injury (CCI) was induced in all but the normal group; electroacupuncture was applied for 30 minutes daily over 7 days.
• Measurements included mechanical and thermal pain thresholds, serum cytokine levels via ELISA, and protein and mRNA expression via Western blot and PCR.
• Compared to the normal group, the model group showed significantly decreased pain thresholds (P<0.001) and increased inflammatory cytokines (P<0.05, P<0.01).
• Electroacupuncture at 2Hz and 50Hz significantly improved pain thresholds (P<0.001, P<0.01) and reduced inflammatory cytokines (P<0.05, P<0.01) compared to the model group.
• The 2Hz group showed increased CB1R expression and decreased NR2B, ERK5 expression (P<0.01), implicating it as the optimal treatment frequency.