RADIATION RESPONSE OF MAMMALIAN CELLS GROWN IN CULTURE. V. TEMPERATURE DEPENDENCE OF THE REPAIR OF X-RAY DAMAGE IN SURVIVING CELLS (AEROBIC AND HYPOXIC).
RADIATION RESPONSE OF MAMMALIAN CELLS GROWN IN CULTURE. V. TEMPERATURE DEPENDENCE OF THE REPAIR OF X-RAY DAMAGE IN SURVIVING CELLS (AEROBIC AND HYPOXIC).
复制标题
培养中生长的哺乳动物细胞的辐射反应。
作者：
M. Elkind;H. Sutton;W. B. Moses;T. Alescio;R. W. Swain
在早期的论文 (1-8) 中，我们报道了培养的哺乳动物细胞对 X 辐射反应的几个方面。这些涉及需氧 (1-3, 6) 和缺氧 (7, 8) 细胞在分次剂量下的存活情况、胸苷类似物 5-溴脱氧尿苷 (4) 的增强作用，以及 X 辐射对存活和非存活细胞分裂特征的影响 (5)。我们对过去这些研究的主要兴趣是亚致死辐照细胞的恢复。也就是说，由于单个哺乳动物细胞群体的存活曲线有一个阈值（或属于 C 型；参考文献 9），因此在产生致死效应之前，损伤必须累积 (2, 10)。4 以指数方式存活的细胞可能不需要损伤累积，尽管同质群体的指数存活也可能是由独特形式的损伤累积造成的 (11)。由于不可能仅从指数混合物构建具有肩部的曲线，因此即使对于不均匀的单细胞群体，阈值型曲线也意味着一个或多个部分需要损伤积累才能致死。对 HeLa (12)、中国仓鼠 (13) 和
In earlier papers (1-8), we reported on several aspects of the response of cultured mammalian cells to X-radiation. These concerned the survival of aerobic (1-3, 6) and hypoxic (7, 8) cells to fractionated doses, the potentiating effect of the thymidine analog 5-bromodeoxyuridine (4), and the effect of X-radiation on the division characteristics of surviving and nonsurviving cells (5). Our principal interest in these past studies has been the recovery of sublethally irradiated cells. That is, since the survival curve of a population of single mammalian cells has a threshold (or is of type C; ref. 9), it follows that damage must be accumulated before a lethal effect is produced (2, 10).4 Cells that survive exponentially may not require damage accumulation, although exponential survival of a homogeneous population can also result from a unique form of damage accumulation (11). Since it is not possible to construct a curve with a shoulder from a mixture of exponentials only, even for an inhomogeneous population of single cells a thresholdtype curve means that one or more moieties require damage accumulation for lethality. Studies with synchronized populations of HeLa (12), Chinese hamster (13), and