Effects of Acupuncture at GB30, GB34, and BL40 on Functional Recovery after Sciatic Crushed Nerve Injury in Rats

Acupuncture has been widely used for pain control. However, the mechanism of pain inhibition by acupuncture is still unclear and evaluation of the physiological effects of acupuncture is limited 1,2) . Many studies have indicated that objective physiological measurements are associated with the determination of the effects of acupuncture. Physiological changes of the acupuncture can be detected in the central nervous system 3,4) . Clinically, acupuncture and moxibustion have been used for relieving peripheral nerve disorder related symptoms such as pain, dysesthesia, numbness and weakness 5) . Peripheral nerves are often damaged by crush, compression, stretching, contusion, ischemia, and various diseases 6) . In the sciatic crushed nerve injury, the affected limb displays characteristics of painful neuropathy such as hyperalgesia, pain-related gait, and swelling 6) . These features are considered the abnormal responses to peripheral stimuli, reflecting the changes of nociceptive neural transmission in the central nervous system. C-Fos expression can serve as a marker of neuronal Background: Peripheral nerve injuries are a commonly-encountered clinical problem and often result in a chronic pain and severe functional deficits. Objectives: The aim of this study was to evaluate the effects of acupuncture on the descending pain and the recovery of the locomotor function that follows sciatic crushed nerve injury in rats. Method: In order to assess the effects of acupuncture on the descending pain and functional recovery, we investigated the walking track analysis, brain-derived neurotrophic factor (BDNF) and its receptor tyrosine receptor kinase B (TrkB) expression in the sciatic nerve, and on the expressions of c-Fos and nitric oxide synthase in the paraventricular nucleus (PVN) of the hypothalamus and in the ventrolateral periaqueductal gray (vlPAG) region resulting from sciatic crushed nerve injury in rats. Results: Acupuncture treatment at Huantiao (GB30), Yanglingquan (GB34), and Weizhong (BL40) facilitated functional recovery. C-Fos and nitric oxide synthase expressions in the brain and BDNF and TrkB expressions in the sciatic nerve were decreased by acupuncture treatment. The most potent effects of acupuncture were observed at the GB30 acupoint. Conclusion: It is possible that acupuncture can be used for pain control and functional recovery from sciatic nerve injury.