Spitkovskiĭ D M, Zaĭtsev S V, Talyzina T A
Radiats Biol Radioecol. 1994 Nov-Dec;34(6):739-47.
The model predicting quantitatively a dose response for genetic lesions in low dose range is presented. The model is based on the concept of programmed initiation of the genetic damage in the subpopulation of specific cells of "evolutionary reserve" (CER). It is demonstrated that complex shape of dose-response curve results from superposition of processes in different subpopulations within exposed cell population, mainly in CER. The model allows us to explain the minimum observed in the dose-response curve at doses corresponding to one (on the average) event of energy deposition per CER with spontaneous aberrations. The equation for dose-response function for dicentrics describes satisfactory experimental observations. Advantage of proposed equation is that it does not deal with free parameters to fit the data. They are determined independently by using known physical and biological characteristics. The data described allow us to suggest that sensitive body for CER is a cell as a whole. Probably, programmed initiation of genetic lesions in CER requires both two hits at cell membrane and radiation effect on cell nucleus.
提出了一种在低剂量范围内对遗传损伤进行剂量反应定量预测的模型。该模型基于“进化储备”特定细胞亚群(CER)中遗传损伤程序性启动的概念。结果表明,剂量反应曲线的复杂形状是由暴露细胞群体中不同亚群(主要是CER)内的过程叠加所致。该模型使我们能够解释在与每个CER平均发生一次能量沉积事件(伴有自发畸变)相对应的剂量下,剂量反应曲线中出现的最小值。双着丝粒剂量反应函数方程对实验观察结果描述良好。所提出方程的优点是它无需处理用于拟合数据的自由参数。这些参数通过使用已知的物理和生物学特征独立确定。所述数据使我们能够推测,CER的敏感体是整个细胞。可能,CER中遗传损伤的程序性启动既需要细胞膜上的两次命中,也需要辐射对细胞核的作用。