The effects of Electro-Acupuncture combined with buprenorphine on expresion of substance P and Calcitonin gene-related peptide in spinal dorsal horn in CFA rats
FAN long,WANG Guolin. Department of Anesthesiology, General Hospital, Tianjin Medical University, Tianjin300052, China. 
        Abstract Objective : To observe the effects of acupuncture combined with 
        基金项目：天津自然科学基金资助项目（043608911）
        作者单位：天津医科大学总医院麻醉科，范隆现在北京首都医科大学宣武医院麻醉科
        通讯作者：王国林，天津医科大学总医院，邮编：300052，E-mail:Wang_guolin@hotmail.com,           

         buprenorphine on expresion of substance P and Calcitonin gene-related peptide in spinal dorsal horn in CFA rats.Method : 30 SD rats were devided into 5 groups: control group; CFA group; EA group;buprenorphine group; EA+buprenorphine group. To establish chronic pain model, 50μl Complete Freund’s adjuvant (CFA) was injected into tibio-tarsal joint of rat in each group except for group A. Buprenorphine was injected by intrathecal route. The change of hyperalgesia score was observed by recording the difference of paw withdral lantency between two hind limbs in hot plate experiment.Immunohistochemistry and computer image analysis system were used to observe the expression of SP and CGRP in spinal dorsal horn of rats. Results : In all the treatment groups, hyperalgesia scores were significantly elevated（P <0.05）, and the expression of SP and CGRP in spinal dorsal horn were significantly decreased(P<0.05). Conclusion :① EA or intrathecal injection of buprenorphine is effective on elevating hyperalgesia score, and decreasing the expresion of SP and CGRP in spinal dorsal horn. ② Compared with buprenorphine treatment, combination treatment with EA and buprenorphine is much more effective .③ Positive corelationship between SP and CGRP is found.
Key word : Pain, substance P ;Calcitonin gene-related peptide ; arthritic rat ; hyperalgesia score ; Electro-Acupuncture ; buprenorphine

        丁丙诺啡是阿片受体激动-拮抗剂，可激动μ受体、κ受体，具有镇痛强度大、不易产生耐受性、成瘾性的优点，被广泛应用于慢性疼痛治疗。电针作为祖国传统医学与现代技术结合的产物，可通过减少脊髓ＳＰ释放量缓解慢性疼痛[1]。相关研究表明，电针的作用主要靠激活μ、δ受体而与κ受体无关[2]。但同时有研究发现，脊髓强啡肽/κ受体系统的激活程度直接关系在慢性炎症痛行为评分 [1]。那么，电针和丁丙诺啡合用治疗慢性炎性疼痛能否产生协同效应？其神经生物学机制是否与改变脊髓背角SP、CGRP表达相关？有关问题在国内外尚未见系统研究。本研究拟观察丁丙诺啡与电针对佐剂致炎大鼠脊髓背角SP、CGRP表达的影响，并探讨其可能的镇痛机制。

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