Yaguchi H, Yoshida M, Ejima Y, Miyakoshi J
Graduate School of Human and Environmental Studies, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan.
Mutat Res. 1999 Apr 6;440(2):189-94. doi: 10.1016/s1383-5718(99)00027-3.
The induction of sister chromatid exchanges (SCEs) was evaluated in the cultured mouse m5S cells after exposure to extremely low frequency magnetic field (ELFMF; 5, 50 and 400 mT). Exposure to 5 mT and 50 mT ELFMF led to a very small increase in the frequency of SCEs, but no significant difference was observed between exposed and unexposed control cells. The cells exposed to 400 mT ELFMF exhibited a significant elevation of the SCE frequencies. There was no significant difference between data from treatments with mitomycin-C (MMC) alone and from combined treatments of MMC plus ELFMF (400 mT) at any MMC concentrations from 4 to 40 nM. These results suggest that exposure to highest-density ELFMF of 400 mT may induce DNA damage, resulting in an elevation of the SCE frequencies. We suppose that there may be a threshold for the elevation of the SCE frequencies, that is at least over the magnetic density of 50 mT.
在培养的小鼠m5S细胞中，评估暴露于极低频磁场（ELFMF；5、50和400 mT）后姐妹染色单体交换（SCE）的诱导情况。暴露于5 mT和50 mT的ELFMF导致SCE频率有非常小的增加，但在暴露细胞和未暴露的对照细胞之间未观察到显著差异。暴露于400 mT ELFMF的细胞表现出SCE频率显著升高。在4至40 nM的任何丝裂霉素-C（MMC）浓度下，单独使用MMC处理的数据与MMC加ELFMF（400 mT）联合处理的数据之间没有显著差异。这些结果表明，暴露于400 mT的最高密度ELFMF可能会诱导DNA损伤，导致SCE频率升高。我们推测，SCE频率升高可能存在一个阈值，即至少超过50 mT的磁密度。
