失血性休克大鼠小肠上皮细胞线粒体DNA、COX基因损伤的研究

Study on damage of genes of mitochondrial DNA encoding cytochrome oxidase of intestinal epithelial cells induced by hemorrhagic shock in rats

目的 探讨失血性休克对大鼠肠上皮细胞线粒体DNA编码细胞色素氧化酶基因的损伤作用。方法 采用失血性休克模型,提取肠上皮细胞线粒体DNA,对细胞色素氧化酶(COXI、COXⅡ、COXⅢ)基因进行PCR扩增,并对PCR产物进行直接测序。结果 细胞色素氧化酶COXI、COXⅡ基因序列产生散在性点突变,其中1只休克鼠细胞色素氧化酶COXI基因从5545-6838出现了35个散在性点突变;1只休克鼠COXⅡ序列在7191-7542有5个点突变(t7191c、t7212c、a7386g、a7483g、e7542g);COXⅢ未出现突变。结论失血性休克缺血缺氧可造成线粒体DNA编码的细胞色素氧化酶基因损伤。

Objective To investigate the effects of hemorrhagic shock on the structure and function of mitochondrial DNA(mtDNA) encoding Cytochrome Oxidase genes in intestinal epithelial cells. Methods Hemorrhagic shock model of rats were used in this experiment. The mtDNA was extracted from the intestinal epithelial cells,polymerase chain reaction (PCR) with different primers of cytochrome oxidase(COX I , COX Ⅱ and COX Ⅲ) was performed. The products of PCR were directly sequenced. Results Hemorrhagic shock could result in the mutagenesis in mitochondrial genome encoding cytochrome oxidase( COX I and COX Ⅱ ). There were 35 point mutations in COX I from 5 545 to 6 838bp in one of shock rat; There were five point mutations in COXⅡfrom 7 191 to 7 542 bp at the site of t7 191c,t7 212c,a7 386g,a7 483g,c7 542g in one shock rats. There was no mutation found in COXⅢ. Conclusion Hemorrhagic shock could significantly induce the damage of the gene of cytochrome oxidase encoded by mtDNA.