细胞色素B5对脑死亡器官捐献供者肝细胞的保护作用

Detection and identification of Cyt B5 as a indicator in the assessment of liver quality under brain death

目的 探讨细胞色素B5对脑死亡供者肝细胞的保护作用.方法 收集30例临床脑死亡供者肝组织和10例正常肝组织样本分别作为研究组和对照组,采用原位末端标记法（TUNEL）检测两组肝细胞凋亡情况,采用蛋白质印迹检测两组肝细胞细胞色素C和细胞色素B5蛋白表达水平,采用逆转录聚合酶链反应（RT-PCR）检测两组肝细胞细胞色素B5 mRNA的表达.结果 研究组与对照组肝细胞TUNEL阳性率分别为15％和63％,两组比较,差异有统计学意义（P＜0.05）.与对照组相比,研究组肝细胞中细胞色素C的表达量显著上升,而细胞色素B5的表达量显著下降,差异均有统计学意义（P＜0.05.与此同时,细胞色素B5的下降与细胞色素C的升高有线性负相关性（R2=0.908 4）;研究组肝细胞细胞色素B5 mRNA的表达量较对照组明显下降,差异有统计学意义（P＜0.05）.结论 脑死亡时供肝细胞凋亡明显增加.细胞色素B5可能参与了脑死亡后肝脏损伤的发生和发展,有望成为脑死亡状态下肝脏质量评估的新指标.

Objective To investigate the effect of cytochrome B5 on hepatocytes under brain death.Method Thirty cases of clinical brain death donor samples and 10 cases of normal liver samples were collected.Western blotting and reverse transcription-polymerase chain reaction were employed to detect quality of the hepacytes and the expression of cytochrome C and cytochrome B5 in the hepatic tissues.Result The expression of cytochrome B5 in brain death models decreased significantly （P〈 0.05） and that of cytochrome C increased significantly （P〈0.05） as compared with control group.Meanwhile,the apoptosis rate of brain death model was significantly higher than controls （P〈0.05）.Conclusion The apoptosis of hepacytes increased significantly under brain death.Cytochrome B5 may participate in the occurrence and development of liver injury after brain death,and is expected to become a new indicator of liver quality evaluation under brain death.