大鼠急性肺栓塞后hnRNP-H_2和FAH的表达变化及其促细胞凋亡的机制研究  

Expression changes of hnRNP-H_2 and FAH and their effects on cell apoptosis in rat lung tissue after acute pulmonary embolism

作　　者：李圣青[1] 刘阿茹[1] 欧阳海峰[1] 简文[1] 赵峰[1] 遆新宇[1] 

机构地区：[1]第四军医大学西京医院呼吸科,西安市710033

出　　处：《中华老年多器官疾病杂志》2008年第4期308-313,共6页Chinese Journal of Multiple Organ Diseases in the Elderly

摘　　要：目的研究大鼠急性肺栓塞模型肺组织中异质性核糖核蛋白H2(hnRNP-H2)和延胡索酰乙酰乙酸水解酶(FAH)的表达变化及其促细胞凋亡的机制。方法建立大鼠急性肺栓塞模型,分别在急性肺栓塞后1、8、24、48h开胸取肺组织。常规提取肺组织的总RNA和总蛋白,以正常组为对照,半定量RT-PCR法测定hnRNP-H2和FAH mRNA表达水平的变化;Western-blot法测定hnRNP-H2和FAH蛋白表达水平的变化。半定量RT-PCR和Western-blot法测定Bcl-x mRNA的不同剪接体Bcl-xS和Bcl-xL在肺栓塞前后的表达变化;Western-blot法测定细胞周期相关蛋白MPM-2和凋亡相关蛋白cytochrome c和caspase-3的表达变化。TUNEL法观察急性肺栓塞后组织细胞的凋亡情况。结果在大鼠急性肺栓塞后,hnRNP-H2的mRNA水平和蛋白水平均逐渐升高,在24h和48h升高最为明显。大鼠急性肺栓塞后Bcl-xS的表达逐渐升高,而Bcl-xL的表达逐渐下降,导致Bcl-xS/Bcl-xL的比例逐渐升高。FAH的mRNA水平和蛋白水平均逐渐下降,在24h和48h下降最为明显。MPM-2,cytochrome c和caspase-3的表达在急性肺栓塞后24h和48h都有明显升高。TUNEL染色发现肺组织内出现明显的细胞凋亡现象。结论大鼠急性肺栓塞后肺组织内hnRNP-H2的表达明显升高,可能导致Bcl-xS/Bcl-xL的比例升高;FAH的表达明显下降,可能导致急性肺栓塞后肺组织细胞周期阻滞于G2/M期,二者共同促进了肺组织细胞的凋亡。Objective To study the expression changes of heterogeneous nuclear ribonucleoprotein H2 （hnRNP-H2） and fumarylacetoacetate hydrolase （FAH） in the lung tissues of a rat model of acute pulmonary embolism （PE） and their effects on the cell apoptosis. Methods A rat model of acute PE was established. The samples of lung tissues were collected at different time points： 1h, 8h, 24h and 48h. The normal rats were used as control. The changes of hnRNP-H2 and FAH mRNA levels were identified by semi-quantitative RT-PCR, and the changes of their protein levels were validated by Western blot method. The methods of seml-quantitative RT PCR and Western blot were also employed to study the expression changes of Bcl-xL and Bcl-xs in the lung tissues after PE, which were the alternative splicing of the apoptotic mediator Bcl-x. The expression changes of cell cycle-related protein MPM-2 and apoptosls-related proteins cytochrome c and caspase-3 were studied by Western blot method. Apoptotic cells in lung tissue sections were identified by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling （TUNEL） method. Results At different time points, the mRNA levels and the protein levels of hnRNP-H2 increased in the lung tissues of rat acute PE models, obviously at 24 and 48h. The expression of Bcl-xs increased gradually after acute PE, .while that of Bcl-xL. decreased obviously, resulting in the up-regulation of the Bcl-xs/Bcl-xL ratio. The mRNA levels and the protein levels of FAH were down-regulated in the lung tissues of rat acute PE models, obviously at 24 and 48h. The expression of MPM-2, cytochrome c and caspase-3 was up-regulated after acute PE, obvi-ously at 24 and 48h. Many apoptotic cells could be observed in the lung tissues by the method of TUNEL after acute PE. Conclusion The expression of hnRNP-H2 increased obviously after acute PE, which might result in the up-regulation of the Bcl-xs/Bcl-XL ratio. The expression of FAH was down-regulated obviously after acute PE, which might result in a t

关 键 词：肺栓塞 核糖核蛋白类 细胞凋亡 

分 类 号：R363[医药卫生—病理学] R563.1[医药卫生—基础医学]