Analgesic Effect of Capsaicin Acupuncture on Neuropathic Pain in Rats

Acupuncture combined with pharmaceutical agents has been used to treat diseases in humans and animals. Capsaicin can relieve pain by desensitization. The present study was conducted to determine whether capsaicin acupuncture as one of pharmaceutical acupunctures can relieve neuropathic pain effectively. 14 days after neuropathic injury, capsaicin was injected at Zusanli acupoint (ST36) and behavioral test was conducted using von Frey filament. After behavioral test, animals were perfused by 4% paraformaldehyde solution. The lumbar spinal cord was then removed and immunohistochemistry was performed to observe c-Fos expression. Capsaicin injected at ST36 acupoint inhibited neuropathic pain behaviors. c-Fos expression level in the lumbar spinal cord had a tendency to decrease in rats treated with capsaicin acupuncture. These results suggest that capsaicin acupuncture as one of pharmaceutical acupunctures may be effective in relieving neuropathic pain.prohibitio