LI Sisi, TU Wenzhan, JIANG Xia, CHEN Wenci, HU Qimiao, GU Pengpeng, JIANG Songhe

(1The Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Zhejiang Wenzhou 325027)

Abstract:  Objective:  To  investigate  the  underlying  mechanisms  of  eletroacupuncture  (EA) analgesic effect, we observed the effect of EA on the behavior change and the expression of TrkB receptor in spinal cord of rats with neuropathic pain caused by chronic constriction injury(CCI). Methods:  Rats were divided into four groups, including normal, sham CCI, CCI and CCI plus EA. Zusanli  acupoint(ST36)  and  Yanglingquan  acupoint(GB34)  were  applied  in  this  study.  The treatment started on the day 7 after CCI surgery and lasted for 7 days. The mechanical withdrawal threshold(MWT)  and  thethermal  withdrawal  latency(TWL)  were  detected  on  the  day  before operation, and day 3, 5, 7, 10, 12 and 14 after CCI operation. At the day 14, the L4-6 spinal cord tissues were taken and used for examing the expression of TrkB receptor.  Resultsz: The value of MWT and TWL were decreased after CCI operation(P＜0.001), however, EA could reverse this phenomenon(P＜0.001). The  expression  of TrkB  receptor  in  spinal  cord  was increased  in  the  CCI group, but it could be inhibited significantly by EA treatment(P＜0.001). Conclusion: These results suggested that TrkB receptor might involved in the development of neuropathic pain. The analgesic effect of EA might be achieved through inhibiting the expression of TrkB receptor.

Key words: Electroacupuncture; Chronic constriction injury; Neuropathic pain; TrkB receptor