Ueno Shunji, Kashimoto Takashige, Susa Nobuyuki, Natsume Hoshiko, Toya Maiko, Ito Nobuhiko, Takeda-Homma Shino, Nishimura Yoshikazu, Sasaki Yu F, Sugiyama Masayasu
Laboratory of Veterinary Public Health, School of Veterinary Medicine, Kitasato University, Higashi 23-35-1, Towada, Japan.
Mutat Res. 2007 Dec 1;634(1-2):135-45. doi: 10.1016/j.mrgentox.2007.06.011. Epub 2007 Jul 10.
The comet assay was performed to elucidate the linearity of calibration curves and detection limits for DNA damage in multiple organs of whole body X-irradiated mice, and rates of reduction in DNA damage by DNA repair during the irradiation period were estimated in the respective organs by comparing the rates of increase in DNA damage at different absorbed dose rates of X-rays. Of the assay parameters, tail length and the percentage DNA in the tail showed a higher sensitivity to DNA damage in most organs than Olive tail moment. Data at the higher absorbed dose rates (2.22 or 1.44 Gy/min) showed good correlations between absorbed doses and these two parameters, with correlation coefficients of more than 0.7 in many organs. However, this assay had difficulty detecting DNA damage at the lower absorption dose rate (0.72 Gy/min). The estimated rates of increase in DNA damage and those of DNA repair during the irradiation period in the respective organs suggested differences in the radiosensitivity of nuclear DNA and DNA repair capacity among organs. Our results indicated that absorbed dose rates of 1.0-1.3 Gy/min or greater were needed to induce detectable DNA damages by the comet assay in many organs.
进行彗星试验以阐明全身X射线照射小鼠多个器官中DNA损伤校准曲线的线性和检测限，并通过比较不同X射线吸收剂量率下DNA损伤的增加率，估算照射期间各器官中DNA修复对DNA损伤的降低率。在检测参数中，尾长和尾部DNA百分比在大多数器官中对DNA损伤的敏感性高于橄榄尾矩。较高吸收剂量率（2.22或1.44 Gy/min）下的数据显示吸收剂量与这两个参数之间具有良好的相关性，许多器官中的相关系数超过0.7。然而，该试验在较低吸收剂量率（0.72 Gy/min）下难以检测到DNA损伤。各器官照射期间DNA损伤的估计增加率和DNA修复率表明，各器官中核DNA的放射敏感性和DNA修复能力存在差异。我们的结果表明，在许多器官中，彗星试验要诱导可检测到的DNA损伤，需要1.0-1.3 Gy/min或更高的吸收剂量率。
Zotero 插件