线粒体机制在右美托咪定保护肾缺血-再灌注损伤中的作用  

Effect of mitochondria mechanism in renal protection of dexmedetomidine on ischemia-reperfusion injury

作　　者：斯妍娜[1] 韩流[1] 张媛[1] 陈利海[1] 徐亚杰[1] 孙凡[1] 潘笑笑 曾令清[1] 王莹[1] 鲍红光[1] 

机构地区：[1]南京医科大学附属南京医院(南京市第一医院)麻醉科,江苏省210006

出　　处：《江苏医药》2016年第7期745-748,共4页Jiangsu Medical Journal

基　　金：国家自然科学基金(81401620);江苏省临床医学科技专项(BC2014012);南京市医学科技发展项目(YKK12085)

摘　　要：目的探讨线粒体机制在右美托咪定(Dex)保护大鼠肾缺血-再灌注(I-R)损伤中的作用。方法健康雄性SD大鼠32只随机均分为假手术组(Con组)、I-R组、Dex组和亲环蛋白D(CypD)抑制剂环孢霉素A组(CsA组)。肾缺血45min后再灌注48h制备肾I-R损伤模型。Dex组和CsA组在缺血前30min分别腹腔注射Dex 50μg/kg和CsA 5mg/kg。再灌注结束时取肾组织,观察肾小管坏死评分,TUNEL法测定细胞凋亡并计算凋亡指数,流式细胞仪测定荧光强度变化率以反映线粒体膜电位。提取肾组织线粒体,LS-55荧光分光光度法测定线粒体540nm处的吸光度(A_(540))值以反映线粒体肿胀度,Western blot测定线粒体CypD表达。结果与Con组比较,I-R组、Dex组和CsA组大鼠的肾小管损伤评分、细胞凋亡指数、CypD表达增加(P<0.05),荧光强度变化率和A_(540)值下降率减少(P<0.05)。与I-R组比较,Dex组和CsA组大鼠肾小管损伤评分、细胞凋亡指数、CypD表达减少(P<0.05),荧光强度变化率和A_(540)值下降率增加(P<0.05)。结论 Dex可维持肾I-R损伤大鼠的线粒体膜电位,降低线粒体肿胀程度,抑制线粒体通透性转换孔开放,改善组织损伤和细胞凋亡。其机制可能与抑制线粒体CypD的表达有关。Objective To investigate the effect of mitochondria mechanism in renal protection of dexmedetomidine on ischemia-reperfusion injury.Methods Thirty-two SD male rats were equally and randomly divided into four groups of Con（sham operated）,I-R,Dex and CsA.Renal ischemia was performed by occlusion of renal pedicles for 45 minutes,which was followed by reperfusion for48 hours.Rats in groups of Dex and CsA were intraperitoneally injected with dexmedetomidine50μg/kg and cyclosporin A（a cyclophilin D inhibitor）5mg/kg at 30 minutes before renal ischemia,respectively.The renal tissues were obtained after reperfusion for determining acute tubular necrosis scale,apoptosis assay（by TUNEL method）and apoptosis index,change ratio of fluorescence intensity by flow cytometry for mitochondria membrance potential.Renal mitochondria was drawn to examine rate of descent for absorbance at 540nm（A（540））by spectrophotometer for swelling of mitochondria and CypD expression by Western blot.Results Compared with group Con,acute tubular necrosis scale,apoptosis index and CypD expression were increased and change ratio of fluorescence intensity and A（540） were decreased in groups of I-R,Dex and CsA（P〈0.05）.Compared with group I-R,acute tubular necrosis scale,apoptosis index and CypD expression were decreased and change ratio of fluorescence intensity and A（540） were increased in groups of Dex and CsA（P〈0.05）.Conclusion Dex can preserve mitochondria membrance potential,reduce swelling of mitochondria,inhibit opening of mitochondrial permeablity transition pore and improve renal injury and cell apoptosis in rats with renal I-R injury,for which the mechanism may be associated with an inhibition of CypD expression.

关 键 词：右美托咪定 缺血-再灌注损伤 线粒体 亲环蛋白D 

分 类 号：R692[医药卫生—泌尿科学]