摘要目的 探讨电离辐射诱导正常人B淋巴细胞线粒体辐射敏感基因mRNA水平的剂量-效应关系.方法 用0、0.5、1、3、5、8、10和15 Gy60 Coγ射线分别照射指数增长期的人淋巴细胞永生化细胞株,24h后用反转录PCR和实时荧光定量PCR方法检测7个相对辐射敏感基因,包括ND3、Cyt b、COX Ⅰ、COXⅡ、COXⅢ、ATPase6和ATPase8基因mRNA的表达水平,观察其剂量-效应关系.结果 60Co γ射线照射后24 h,线粒体7个辐射敏感基因表达总体上调.线粒体呼吸链复合体Ⅳ亚基Ⅰ (COX Ⅰ)基因表达在受到8 Gy照射后增强最明显,为对照组的13倍左右.除COX Ⅰ和COXⅡ外,其余5个基因在受照后表现出一定的剂量-效应关系.其中,ND3、ATPase6和ATPase8这3个基因在3 ～15 Gy的范围内线性关系良好,而COXⅢ基因在3～10 Gy的范围内也有十分良好的线性关系.结论 60Co γ射线照射后24 h,线粒体基因表达水平总体上调,其中ND3、ATPase6、ATPase8和COXⅢ这4个基因在一定剂量范围内线性关系良好,可以作为联合辐射损伤生物标志物进一步研究.

abstractsObjective To investigate the dose-effect relationship of mRNA level of sensitive mitochondrial genes in human lymphoblastoid cells induced by ionizing radiation.Methods Seven human sensitive genes,including ND3,Cyt b,COX Ⅰ,COX Ⅱ,COX Ⅲ,ATPase6 and ATPase8 were chosen.Changes of mRNA level of these genes were detected by RT-PCR and Real-Time PCR at 24 h after irradiation in human lymphoblastoid cells,which were exposed to 0 - 15 Gy of 60 Co γ-rays.Results The expression of these 7 genes at mRNA level was up-regulated 24 h after irradiation in human lymphoblastoid cells.The level of gene expression of COX Ⅰ,which belongs to complex Ⅳ of mitochondrial respiratory chain,was most obvious,and the peak occurred after irradiation of 8 Gy,which was 13 times of the control group.A good dose-effect relationship was showed for COX Ⅲ gene expression at dose range of 3 -10 Gy as well as 3 - 15 Gy for other 3 genes including ND3,ATPase6 and ATPase8.Conclusions Gene expression levels of COX Ⅲ,ND3,ATPase6 and ATPase8 24h post-irradiation at certain irradiation dose range could be used for radiation damage biomarkers.