小剂量电离辐射引起拓扑异构酶Ⅱα表达的变化  

Effection of low dose ionizing radiation on expression of DNA topoisomerase Ⅱα

作　　者：李华[1] 刘雯[1] 李锦燕[1] 左伋[1] 

机构地区：[1]复旦大学医学院细胞与遗传医学系,上海200032

出　　处：《中华放射医学与防护杂志》2003年第1期1-3,共3页Chinese Journal of Radiological Medicine and Protection

基　　金：国家自然科学基金资助项目 (3 0 10 0 0 3 7)

摘　　要：目的　探讨小剂量电离辐射引起DNA拓扑异构酶Ⅱα(TOPOⅡα)的表达变化。方法用免疫细胞化学染色和Westernblot的方法 ,检测了HeLa细胞在 5Gyγ射线照射后的时间效应和小于 5Gy的剂量效应 ,以及小剂量的多次累积效应。结果　 5Gyγ射线照射后 4hTOPOⅡα开始下降 ,12h降为最低 ,16h开始回升 ;在小于或等于 5Gy时 ,随剂量增加 ,TOPOⅡα的表达下降逐渐明显 ;且较小剂量具多次累积效应。结论　小剂量的电离辐射引起的TOPOⅡα的表达变化具时间效应、剂量效应和多次累积效应。Objective\ To explore the changes of topoisomerase (TOPO) Ⅱα expression,the behavior of TOPO Ⅱα in HeLa cells treated with low dose ionizing radiation was studied. Methods\ The kinetics of TOPO Ⅱα was measured by immunocytochemistry and Western blot. Results\ A profound and transient decrease of TOPOⅡα after γ irradiation with 5 Gy was detected,the decrease began from 4 h after irradiation,reached the lowest level at 12 h,and began to return at 16 h.Given low dose γ\|rays,the level decreased along with the increase of dose.The level of decrease after several times irradiation was higher than that after only one time. Conclusions\ This observation indicates that the decrease of TOPO Ⅱα after γ\|irradiation is time\|dependent and dose\|dependent,and the effect of low dose γ irradiation can be accumulated.\;

关 键 词：剂量 电离辐射 拓扑异构酶Ⅱα 基因表达 免疫组织化学 时间 

分 类 号：Q55[生物学—生物化学]