Electroacupuncture alleviates pain-like behaviors through modulating DNMT3a/MOR signaling pathway in CCI rats.

Researchers investigated how electroacupuncture (EA) relieves nerve pain using rats with chronic constriction injury, a model that mimics neuropathic pain in humans. The study focused on two acupuncture points: Zusanli (ST36) on the lower leg and Yanglingquan (GB34) near the knee. Rats received 30-minute EA treatments daily for seven days, starting one week after nerve injury. The research team measured pain sensitivity by testing how quickly rats withdrew their paws from uncomfortable stimuli, and they examined molecular changes in nerve tissue. The results showed that nerve injury increased levels of a protein called DNMT3a while decreasing mu opioid receptors (MOR), which are natural pain-relief mechanisms in the body. EA treatment reversed these changes, reducing DNMT3a and increasing MOR expression in the dorsal root ganglion, a cluster of nerve cells near the spinal cord. This led to measurable pain relief, with treated rats showing improved pain thresholds. The study also found that EA reduced inflammation-related proteins and decreased activation of glial cells, which contribute to chronic pain. These findings suggest that EA may relieve neuropathic pain by affecting DNA methylation processes that control natural opioid receptor production. For patients suffering from nerve pain after injury, electroacupuncture appears to work through specific biological mechanisms rather than placebo effects alone. The treatment modulated pain signaling pathways in both the peripheral nervous system and spinal cord. If you're considering acupuncture for neuropathic pain, seek treatment from a licensed acupuncturist trained in electroacupuncture techniques.

This animal study investigated electroacupuncture's mechanism of action in chronic constriction injury (CCI) rats modeling neuropathic pain. EA was applied at ST36 and GB34 unilaterally for 30 minutes daily over 7 days, beginning one week post-CCI. Researchers assessed paw withdrawal threshold (PWT) and paw withdrawal latency (PWL) as pain measures, and used Western blot, RT-qPCR, and immunofluorescence to evaluate molecular changes in dorsal root ganglion (DRG) and spinal cord dorsal horn (SCDH). Results demonstrated that EA significantly reversed CCI-induced upregulation of DNMT3a and downregulation of mu opioid receptors (MOR) in DRG tissue. EA treatment also decreased expression of pain-related signals (Fos, ERK1/2, pERK1/2) and glial activation markers (CD11b, Iba1, GFAP) in both DRG and SCDH. Clinical takeaway: EA at ST36/GB34 may produce analgesia in neuropathic pain through epigenetic modulation—specifically by inhibiting DNMT3a, thereby increasing endogenous MOR expression and reducing neuroinflammatory glial activation.