Effect of Electroacupuncture Intervention on Expression of CGRP, SP, COX-1, and PGE2 of Dorsal Portion of the Cervical Spinal Cord in Rats with Neck-Incision Pain

• Published in: Evidence-based complementary and alternative medicine Vol. 2013; no. 2013; pp. 1 - 9
• Main Authors: Wang, Jun-ying, Chen, Shu-ping, Qiao, Li-na, Liu, Jun-ling, Zhang, Jian-liang, Gao, Yong-hui, Yang, Yong-sheng
• Format: Journal Article
• Language: English
• Published: Cairo, Egypt Hindawi Puplishing Corporation 01.01.2013; Hindawi Publishing Corporation; Hindawi Limited
• Subjects: Acupuncture; Analgesia; Analgesics; Calcitonin; Calcitonin gene-related peptide; Chinese medicine; Cyclooxygenase-1; Electroacupuncture; Enzyme-linked immunosorbent assay; Gene expression; Immunofluorescence; Laboratory animals; Neck; Neurokinin; Neurokinin NK1 receptors; Neurosciences; Pain; Pain perception; Prostaglandin E2; Rats; Rodents; Spinal cord; Stimulation; Substance P; Surgery; Thyroid; Thyroid gland; China
• ISSN: 1741-427X; 1741-4288
• DOI: 10.1155/2013/294091

The present study was aimed to determine if cervicospinal substance P (SP) and its neurokinin-1 receptor (NK-1R), calcitonin gene-related peptide (CGRP), cyclooxygenase-1 (COX-1), and prostaglandin E2 (PGE2) were involved in electroacupuncture (EA) analgesia in neck-incision pain rats. EA intervention was applied to bilateral Futu (LI18), Hegu (LI4)-Neiguan (PC6), and Zusanli (ST36)-Yanglingquan (GB34) for 30 min. Cervicospinal SP and CGRP immunoactivity was detected by immunofluorescence technique, NK-1R and COX-1 protein and mRNA expression levels were determined using Western blot and real-time PCR, respectively, and PGE2 content was measured using ELISA. Outcomes indicated that EA of EA-LI18 and LI4-PC6 (not ST36-GB34) significantly suppressed neck-incision induced decrease of thermal pain threshold (P<0.05). EA stimulation of LI18 and LI4-PC6 markedly inhibited neck-incision induced upregulation of SP and CGRP immunoactivity, NK-1 R and COX-1 mRNA and protein expression levels, as well as the increase of PGE2 content in the dorsal cervicospinal cord (P<0.05). These findings showed that LI18 and LI4-PC6 EA stimulation-induced downregulation of SP, CGRP, NK-1R, COX-1, and PGE2 levels in the dorsal cervicospinal cord may contribute to their effects in relieving neck-incision pain. This study highlights the targets of EA intervention for reducing post-thyroid-surgery pain for the first time.