Kondrashova T V, Poriadkova N A, Aref'eva O V, Luchnik N V
Genetika. 1990 Sep;26(9):1671-4.
Formation of SCE was studied in lymphocytes irradiated by 60Co gamma-rays at the G1 stage of the first or second mitotic cycles. The yield of SCEs induced by irradiation in the presence of 5-bromodeoxyuridine (BrdU) proved to be significantly higher than that obtained in the absence of BrdU. The enhancing influence of BrdU on SCE induction depends on neither replication cycle nor the molecular constitution of chromosomes under irradiation. Direct modification of chromosomal radiosensitivity by BrdU is excluded. The results obtained suggest the interference of free BrdU present in culture medium with processes of DNA reparation at the G1 stage.
在第一个或第二个有丝分裂周期的G1期，对受60Coγ射线照射的淋巴细胞中姐妹染色单体交换（SCE）的形成进行了研究。结果表明，在5-溴脱氧尿苷（BrdU）存在的情况下，照射诱导的SCE产量显著高于不存在BrdU时获得的产量。BrdU对SCE诱导的增强作用既不取决于复制周期，也不取决于照射时染色体的分子结构。排除了BrdU对染色体放射敏感性的直接修饰作用。所得结果表明，培养基中存在的游离BrdU会干扰G1期的DNA修复过程。
