摘要
目的探讨右美托咪定（Dexmedetomidine，Dex）对晶状体囊外摘出术（ECLE）后小鼠远期认知功能的作用。方法实验用成年雄性C57BL／6J小鼠40只，采用随机数字表法分为对照组（c组）、ECLE组、生理盐水组（Ns组）和Dex组，每组10只。ECLE模型制备后3d，C组和ECLE组进行Moms水迷宫试验，检测海马组织湿／干重比（W／D）和总含水量（TWC），逆转录-聚合酶链反应和蛋白免疫印迹法分别检测海马组织天冬氨酸特异性半胱氨酰蛋白酶（caspase）-12mRNA及蛋白表达水平，原位末端细胞凋亡法检测海马组织细胞凋亡指数（AI）。Dex组小鼠术毕苏醒即刻经腹腔注射Dex25μg·kg-1·d-1，Ns组给予等容量生理盐水，连续30d，随后检测前述项目。结果与c组比较，ECLE组小鼠逃避潜伏期及游泳距离均延长（P〈0．05），海马组织W／D、TWC及AI均增加（P〈0．05），海马组织caspase-12mRNA及蛋白表达水平均增加（P〈0．05）。与NS组比较，Dex组小鼠逃避潜伏期及游泳距离均缩短（P〈0．05），海马组织W／D、TWC及AI均减少（P〈0．05），海马组织caspase-12mRNA及蛋白表达水平均降低（P〈0．05）。结论Dex可改善ECLE后小鼠远期认知功能，其机制可能与其抑制海马组织caspase-12介导的细胞凋亡有关。
Objective To investigate the effect of Dexmedetomidine （Dex） on long-term cognitive function after extracapsular lens extraction （ECLE） in mice. Methods Forty adult male C57BL/6J mice were randomly divided into control group （C group）, ECLE group, normal saline group （NS group） and Dex group with 10 mice in each group. Three days after ECLE model was made, the mouse in C group and ECLE group underwent Morris water maze test, then they were euthanized and hippocampus tissue was immediately excised for determination of wet weight to dry weight （W/D） and total water content （ TWC ）. The transcription levels of eycteinyl aspirate-specific protease-12 （ caspase-12 ） mRNA and its protein in hippocampus tissue were detected respectively by reverse transcription polymerase chain reaction （PCR） and Western Blot. Apoptosis index （AI） of hippoeampus tissue was determined by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling assay. After the mice regained consciousness post the operation, animals received intraperitoneally Dex at a dose of 25 μg · kg- 1 . d -1 for 30 consecutive days in Dex group. Animals of NS group were accepted intraperitoneally injection with the same volume of normal saline. The evaluation indexes mentioned above were programmed at 30 dyas post intraperitonedlly injection. Results Compared with C group, the escape latency and swimming distance were prolonged transcription in ECLE group （ both P 〈 0.05 ）, the value of W/D, TWC and AI were increased （ all P 〈 0.05 ）, and theexpression of easpase-12 and mRNA transcription in hippocampus tissue were significantly higher （ both P 〈 0. 05） in ECLE group. Compared with NS group, the escape latency and swimming distance were shortened in Dex group（ both P 〈0.05）, the value of W/D, TWC and AI were decreased （ all P 〈 0.05 ）, and the expression of caspase-12 and mRNA protein transcription in hippocampus tissue were significantly lower （both P 〈 0. 05） in Dex group. Conclusion The treatment of Dex could improve the long-term cognitive function after ECLE in mice, and the mechanism may be through inhibiting apoptosis mediated by caspase-12 in hippocampus tissue.
出处
《中华眼外伤职业眼病杂志》
2015年第8期580-584,共5页
Chinese Journal of Ocular Trauma and Occupational Eye Disease
