彗星分析技术检测辐射和化学物质诱导的DNA损伤

目的： 用彗星分析技术(comet assay)检测邻苯二胺(o-phenylenediamine, o-PDA)和60 Coγ-射线对CHL细胞DNA的损伤。 方法： CHL细胞经0、 2、 4、 6、 8 μmol / L的邻苯二胺染毒和0、 2、 4、 6、 8、 10、 15 Gy 的60 Co γ-射线照射后，进行单细胞凝胶电泳，测定彗星尾长。采用Origin 4.2软件建立两种诱变剂的剂量与CHL细胞彗星尾长的剂效关系。 结果： DNA的损伤程度(以彗星尾长为指标)随60 Coγ-射线剂量的加大和o-PDA浓度的增加而增强，CHL细胞彗星尾长(TL)与60 Coγ-射线的剂效关系符合线性平方模型：TL=20.41＋2.42D＋0.38D 2；与o-PDA浓度的剂效关系符合线性平方模型：TL=1.90＋1.46C＋0.52C 2。 结论： 60 Co γ-射线剂量和o-PDA的浓度与细胞DNA损伤程度具有剂效关系；彗星分析是一种分析环境危害因子遗传毒性的有效技术。

MEASUREMENT OF DNA DAMAGES INDUCED BY RADIATION AND CHEMICALS USING COMET ASSAY

Purpose: To study DNA damages induced by 60 Co γ-radiation and o-phenylenediamine(o-PDA) using comet assay. Methods: The DNA damages induced by 0,2,4,6,8,10,15 Gy 60 Co γ-rays and 0,2,4,6,8 μmol / L o-PDA were measured using comet assay. The dose-respose relationship of the CHL cell tail length and the dose of the two type of mutagen were established with Origin 4 software. Results: The tail length of comet, index of DNA damage in this experiment， increased with the dose of 60 Co γ-ray and concentration of o-PDA, respectively. The dose-respose relationship of the CHL cell tail length(TL)and the dose of 60 Coγ-ray fitted for linear-quadratic model: TL=20.41＋2.42D＋0.38D 2; The dose-response relationships for DNA damage induced by o-PDA fitted for linear-quadratic model: TL=1.90＋1.46C＋0.52C 2. Conclusion: The comet assay is a useful tool for determining the genotoxicity of environmental agents.