Rubin D B, Drab E A, Ward W F, Bauer K D
Radiat Res. 1986 Nov;108(2):206-14.
The purpose of this experiment was to determine the effect of ionizing radiation on cell number, lactate dehydrogenase (LDH) release, cell cycle distribution, [3H]thymidine incorporation, and autoradiographic labeling index in bovine aortic endothelial cells in vitro. Confluent endothelial monolayers were exposed to single doses of 0.5-10 Gy of 60Co gamma rays and were analyzed from 2 to 24 h postirradiation. Irradiated monolayers exhibited a time- and dose-dependent decrease in cell number, increase in LDH release, and redistribution of cells in the cell cycle. Cell cycle redistribution included an increase in the proportion of cells in S phase at 4 h after irradiation and a decrease in S phase at 24 h. The cells also exhibited a decrease in [3H]thymidine incorporation as early as 2 h after 5 Gy. This represented the most rapid radiation response observed in the present study. These data demonstrate that radiation cytotoxicity in confluent, plateau-phase endothelial monolayers is accompanied by changes in the cell cycle distribution of adherent cells, and that reduced [3H]thymidine incorporation is an early marker of radiation injury in this clinically important cell type.
本实验的目的是确定电离辐射对体外培养的牛主动脉内皮细胞的细胞数量、乳酸脱氢酶（LDH）释放、细胞周期分布、[3H]胸苷掺入及放射自显影标记指数的影响。将汇合的内皮细胞单层暴露于单剂量0.5 - 10 Gy的60Coγ射线，并在照射后2至24小时进行分析。照射后的单层细胞呈现出细胞数量的时间和剂量依赖性减少、LDH释放增加以及细胞在细胞周期中的重新分布。细胞周期重新分布包括照射后4小时S期细胞比例增加，24小时S期细胞比例减少。在5 Gy照射后2小时，细胞的[3H]胸苷掺入就开始减少。这是本研究中观察到的最快速的辐射反应。这些数据表明，汇合的、处于平台期的内皮细胞单层中的辐射细胞毒性伴随着贴壁细胞的细胞周期分布变化，并且[3H]胸苷掺入减少是这种临床重要细胞类型辐射损伤的早期标志物。
