Meechan P J, Haraf D J, Diamond A M, Grdina D J
Dept. of Biological Sciences, Northern Illinois University, Dekalb 60115.
Int J Radiat Oncol Biol Phys. 1992;23(5):999-1002. doi: 10.1016/0360-3016(92)90905-w.
A series of cell lines were previously generated from the radiation sensitive Chinese hamster ovary line xrs5 after treatment with azacytidine. Six of these lines have been examined for their resistance to killing by 0 to 20 Gray of 60Co gamma rays and the amount of radioprotection afforded by treatment with the drug 2-[(aminopropyl)amino]ethanethiol (WR-1065). As xrs5 cells have lost the ability to be protected by WR-1065, studies were performed to determine whether reversion to radio-resistance correlated with recovery of aminothiol radioprotection. Treatment of azacytidine-treated, radiation sensitive and resistant cells with four millimolar WR-1065 30 minutes prior to irradiation enhanced survival after exposure to gamma radiation, although the enhancement in survival was less than for wild type Chinese hamster ovary K1 cells. The data suggest that there is not an absolute linkage between recovery of gamma ray radiation resistance and protection by WR-1065 and other factors, such as chromatin organization, must play a role.
先前用氮杂胞苷处理辐射敏感的中国仓鼠卵巢细胞系xrs5后，产生了一系列细胞系。已检测其中6个细胞系对0至20戈瑞的60Coγ射线杀伤的抗性，以及用药物2-[(氨丙基)氨基]乙硫醇（WR-1065）处理所提供的辐射防护量。由于xrs5细胞已丧失被WR-1065保护的能力，因此进行了研究以确定恢复抗辐射能力是否与氨基硫醇辐射防护的恢复相关。在照射前30分钟用4毫摩尔WR-1065处理经氮杂胞苷处理的辐射敏感和抗性细胞，可提高γ射线照射后的存活率，尽管存活率的提高低于野生型中国仓鼠卵巢K1细胞。数据表明，γ射线辐射抗性的恢复与WR-1065的保护之间不存在绝对联系，其他因素，如染色质组织，必定起作用。
