Ishii Y, Bender M A
Mutat Res. 1978 Sep;51(3):411-8. doi: 10.1016/0027-5107(78)90129-x.
Newly developed techniques for the detection of sister-chromatid exchanges (SCE) require the substitution of 5-bromodeoxyuridine (BrdU) for thymidine in DNA. We investigated the possibility of interactions between BrdU and one mutagen--carcinogen, mitomycin C (MMC) for the induction of both chromosomal aberrations and SCE in human peripheral lymphocytes in culture. No effect on aberration yield was found. Neither comparisons between the yields of SCE by BrdU substitution and differential staining and those detected by tritiated thymidine incorporation and autoradiography nor between the yields of SCE for different levels of BrdU incorporation provided any evidence of synergism. It was found, however, that MMC persists in cultures and continues to increase SCE frequencies for about 30 h. It was also observed that some MMC-induced DNA lesions persist long enough so that some of those present prior to S phase of the first cell cycle cause additional SCE in the third cycle.
用于检测姐妹染色单体交换（SCE）的新开发技术要求在DNA中用5-溴脱氧尿苷（BrdU）替代胸腺嘧啶核苷。我们研究了BrdU与一种诱变致癌物丝裂霉素C（MMC）之间相互作用的可能性，以诱导培养的人外周血淋巴细胞中的染色体畸变和SCE。未发现对畸变率有影响。无论是通过BrdU替代和差异染色检测的SCE产率与通过氚化胸腺嘧啶核苷掺入和放射自显影检测的SCE产率之间的比较，还是不同BrdU掺入水平的SCE产率之间的比较，均未提供任何协同作用的证据。然而，发现MMC在培养物中持续存在，并在约30小时内持续增加SCE频率。还观察到一些MMC诱导的DNA损伤持续时间足够长，以至于在第一个细胞周期的S期之前存在的一些损伤会在第三个周期中导致额外的SCE。
