海马注射miR-181c对CCI模型大鼠机械痛和NF-L表达的影响  

The effects of intra-hippocampal injection of miR-181c on mechanical hyperalgesia and the expression of NF-L in CCI rats

作　　者：吴愚 唐其 徐陶 李映莹 石琬岚 付小龙 曾俊伟 Wu Yu;Tang Qi;Xu Tao;Li Yingying;Shi Wanlan;Fu Xiaolong;Zeng Junwei(Department of Physiology,Zunyi Medical University,Zunyi 563000,China;University Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education,Zunyi Medical University,Zunyi 563000,China)

机构地区：[1]遵义医科大学生理学教研室,遵义563000 [2]遵义医科大学基础药理教育部重点实验室暨特色民族药教育部国际合作联合实验室,遵义563000

出　　处：《神经解剖学杂志》2021年第4期399-404,共6页Chinese Journal of Neuroanatomy

基　　金：国家自然科学基金(31860291);贵州省教育厅创新群体重大研究项目(黔教合KY字[2018]025);贵州省研究生科研基金立项课题(黔教合YJSCXJH[2019]095)。

摘　　要：目的:在坐骨神经缩窄性损伤(CCI)大鼠海马背侧CA1区给予miR-181c激动剂及抑制剂,观察大鼠机械痛阈以及海马神经微丝轻链多肽(NF-L)表达变化。方法:雄性SD大鼠分为假手术组(sham)、CCI组+生理盐水组、CCI+miR-181c激动剂组和CCI+miR-181c抑制剂组。在术前和术后第1、3、5、7、10和14 d测定机械缩足反射阈值(MWT);免疫组化观察NF-L表达,Western Blot检测三结构蛋白2(TRIM2)、NF-L和N-甲基-D天门冬氨酸受体NR1亚单位(NMDAR1)的表达。结果:与sham组相比,CCI+生理盐水组MWT降低(P <0.05);与CCI组相比,miR-181c激动剂组MWT明显升高(P <0.05),而miR-181c抑制剂组MWT进一步降低(P <0.05)。免疫组化观察到,与sham组相比,CCI+生理盐水组NF-L阳性纤维减少;与CCI组相比,CCI+miR-181c激动剂组NF-L阳性纤维增多,而CCI+miR-181c激动剂组NF-L阳性纤维减少。Western Blot实验显示,与sham组相比,CCI+生理盐水组海马TRIM2的表达升高(P <0.05),而NF-L与NR1的表达下降(P <0.05);与CCI组相比,CCI+miR-181c激动剂组TRIM2表达下降(P <0.05)而NF-L与NMDAR1(NR1)表达上升(P <0.05);而CCI+miR-181c抑制剂组TRIM2表达上升(P <0.05),NF-L与NR1表达下降(P <0.05)。结论:海马CA1区给予miR-181c可以减轻CCI大鼠机械痛敏,抑制海马TRIM2表达,促进NF-L与NR1表达上调,减轻海马神经元损伤。Objective: To investigate the effects of intra-CA1 hippocampal injection of miR-181c agomir or antagomir on mechanical hyperalgesia and the expression of Neurofilament Light Chain in hippocampus of rats with chronic constriction injury (CCI) of the sciatic nerve. Methods: Male Sprague-Dawley rats were randomized into four groups:sham group,CCI + saline goup,CCI + miR-181c agomir group,and CCI + miR-181c antagomir group. Mechanical withdrawal threshold (MWT) was evaluated before the surgery and on 1,3,5,7,10,and 14 day after surgery. The expression of NF-L in the CA1 region of rat hippocampus was observed by immunohistochemistry. The expression of TRIM2,NF-L,and NR1 was detected by Western Blot. Results: MWT in CCI + saline group was significantly lower than that of the sham group (P < 0. 05). Repeated administrated of miR-181c agomir attenuate CCI-induced mechanical hyperalgesia (P < 0. 05) and miR-181c antagomir enhanced CCI-induced mechanical hyperalgesia (P < 0. 05). Immunohistochemistry staining revealed that NF-L was significantly reduced in CCI + saline group and was increased after miR-181c agomir treatment. Western Blot results demonstrated that,for the saline-treated CCI rats,the expression of TRIM2 in hippocampal tissue was significantly increased compared with sham group (P < 0. 05),while the expression of NF-L and NR1 were significantly decreased compared with sham group (P < 0. 05). Administration of miR-181c agomir reversed CCI-induced the increased expression of TRIM2 and the decreased expression of NF-L and NR1 (P <0. 05). However,administration of miR-181c antagomir enhanced CCI-induced the increased expression of TRIM2 and the decreased expression of NF-L and NR1 (P < 0. 05). Conclusion: Intra-hippocampal CA1 injection of miR-181c agomir attenuated CCI-induced mechanical hyperalgesia,reduced the TRIM2 expression and enchanced NF-L and NR1 expression level with correlated morphometric recovery.

关 键 词：miR-181c 神经痛 海马 三结构蛋白2 神经微丝轻链多肽 N-甲基-D天门冬氨酸受体NR1亚单位 大鼠 

分 类 号：R402[医药卫生—临床医学]