高位脊髓损伤对大鼠心肌细胞线粒体电压依赖性阴离子通道2表达的影响
Effect of high-level spinal cord injury on expression of mitochondrial voltage-dependent anion channel 2 in rat cardiomyocytes
目的 评价高位脊髓损伤对大鼠心肌细胞线粒体电压依赖性阴离子通道2(VDAC2)表达的影响.方法 清洁级健康成年雄性SD大鼠48只,体重200~250 g.采用随机数字表法分为2组(n=24):假手术组(S组)和高位脊髓损伤组(H组).H组采用Allens打击法,制备大鼠高位脊髓损伤模型,S组只暴露脊髓,不进行打击.于打击后6、12、24和48 h(T1~4)时各组随机取6只大鼠麻醉后处死,剪取心尖部心肌组织,透射电镜下观察心肌细胞形态学;采用原位末端标记法检测心肌细胞凋亡率;分别采用Western blot法和RT-PCR法检测心肌细胞Bax、Bcl-2和VDAC2及其mRNA的表达水平,计算Bax/Bcl-2蛋白及其mRNA比值.结果 与S组比较,H组T1~4时细胞凋亡率和Bax/Bcl-2蛋白及其mRNA比值升高,T2~4时VDAC2及其mRNA表达下调(P<0.05或0.01),心肌细胞病理学损伤加重.结论 高位脊髓损伤大鼠心肌损伤的机制与心肌细胞线粒体VDAC2表达下调,促进细胞凋亡有关.
更多Objective To evaluate the effect of high-level spinal cord injury(SCI)on the expression of mitochondrial voltage-dependent anion channel 2(VDAC2)in rat cardiomyocytes.Methods Forty-eight pathogen-free healthy adult male Sprague-Dawley rats,weighing 200-250 g,were divided into 2 groups(n=24 each)using a random number table:sham operation group(group S)and high-level SCI group(group H).The animals were anesthetized with intraperitoneal chloral hydrate and subjected to SCI using the modified Allen weight-drop method in group H.The spinal cord was only exposed in group S.At 6,12,24 and 48 h after SCI(T1-4),6 rats in each group were randomly selected and sacrificed,and myocardial specimens were collected from the cardiac apex for microscopic examination of the cell morphology(with a transmission electron microscope) and for determination of cell apoptosis(by TUNEL assay),expression of Bax,Bcl-2 and VDAC2 protein and mRNA in cardiomyocytes(by Western blot and real-time polymerase chain reaction,respectively).The apoptosis rate and ratios of Bax/Bcl-2 protein and mRNA were calculated.Results Compared with group S,the apoptosis rate and ratios of Bax/Bcl-2 protein and mRNA were significantly increased at T1-4,the expression of VDAC2 protein and mRNA was significantly down-regulated at T2-4(P<0.05 or 0.01),and the pathologic changes of cardiomyocytes were aggravated in group H.Conclusion The mechanism of myocardial damage is related to down-regulation of mitochondrial VDAC2 expression in cardiomyocytes and promotion of cell apoptosis in rats with high-level SCI.
More- 浏览:98
- 被引:2
- 下载:124
相似文献
- 中文期刊
- 外文期刊
- 学位论文
- 会议论文