摘要
目的观察A型肉毒毒素(BTX-A)注射对佐剂性关节炎大鼠疼痛行为及脊髓小胶质细胞激活、肿瘤坏死因子-α(TNF-α)表达的影响,并探讨BTX-A治疗佐剂性关节炎疼痛的可能机制。方法采用随机数字表法将60只清洁级雄性SD大鼠分为假手术组、完全弗氏佐剂组(模型组)和BTX-A组,每组20只大鼠。除假手术组外,其余2组均于左后肢踝关节腔注射50μl CFA建立佐剂性关节炎疼痛模型,假手术组大鼠关节腔内注射50μl生理盐水作为对照。造模成功后假手术组和模型组大鼠左后肢踝关节腔注射20μl生理盐水,BTX-A组大鼠注射20μl 5 U BTX-A。于造模前1天、造模后第1,3,7,14,21天及给药后第1,3,7,14天对各组大鼠机械痛阈和热痛阈进行测定;并于测试后取出相应时间点脊髓组织,采用免疫蛋白印迹法、免疫荧光染色法检测离子钙接头蛋白(IBA-1)表达及IBA-1免疫阳性细胞(IBA-1-IR)数量;另采用ELISA法、实时荧光定量逆转录-聚合酶链反应(RT-PCR)检测脊髓水平TNF-α蛋白及TNF-αmRNA表达情况。结果与模型组比较,BTX-A组踝关节腔注射BTX-A后第3天时其机械痛撤足阈值及热痛阈潜伏期均明显增加,直到注射后第14天时差异均具有统计学意义(P<0.01);脊髓水平IBA-1蛋白表达显著降低,IBA-1免疫阳性细胞数量明显下调(P<0.01);TNF-α蛋白及TNF-αmRNA表达均明显降低(P<0.05)。结论BTX-A可减轻CFA诱导的关节炎疼痛,其镇痛机制可能与抑制脊髓小胶质细胞活化及TNF-α释放有关。
Objective To observe the effect of botulinum toxin A(BTX-A)on pain,the activation of microglia and the expression of tumor necrosis factor-α(TNF-α)in the spinal cord in arthritis,and to explore how BTX-A treatment relieves pain.Methods Sixty clean,male Sprague-Dawley rats were randomly divided into a sham operated group,a Freund′s adjuvant group and a BTX-A group.The ankle cavities of the left hind limbs of all of the rats except those in the sham group were injected with 50μl of Freund′s adjuvant to establish an arthritis pain model.The sham operated group received 50μl of saline solution as controls.Afterward the sham operation group and the Freund′s adjuvant group were given another 20μl of normal saline,while the BTX-A group was injected with 20μl of botulinum toxin A,again into the ankle joint cavity of the left hind limb.The mechanical and thermal pain thresholds of the rats in each group were measured 1 day before the modeling and 1,3,7,14 and 21 days afterward.Western blotting and immunofluorescence staining were used to detect the expression of IBA-1 and IBA-1-IR.In addition,the expression of TNF-αprotein and TNF-αmRNA in the spinal cord was detected using ELISA and RT-PCR.Results Compared with the Freund′s adjuvant group,the latency of the mechanical and thermal pain thresholds had increased significantly in the BTX-A group after 3 days.The differences remained significant until the 14th day after the injection.The expression of IBA-1 protein and the number of immunopositive cells in the spinal cord decreased significantly,as did the expression of TNF-αprotein and mRNA.Conclusions Botulinum toxin A can alleviate the pain induced by Freund′s adjuvant.The analgesic mechanism may be related to inhibiting the activation of spinal microglia and the release of TNF-α.
作者
史小娟
初晓
王琳
石奇琳
杨慧
李铁山
Shi Xiaojuan;Chu Xiao;Wang Lin;Shi Qilin;Yang Hui;Li Tieshan
出处
《中华物理医学与康复杂志》
CAS
CSCD
北大核心
2020年第7期594-600,共7页
Chinese Journal of Physical Medicine and Rehabilitation
基金
山东省自然科学基金(ZR2018MH031)。
