中文摘要：

为探讨纳米TiO2对肝、肾细胞DNA的损伤效应，实验制备了锐钛矿型纳米TiO2颗粒（20-100nm），并采用不同浓度的纳米TiO2（0、0.1、0.2、0.4、0.8mg·mL^-1）对25只昆明雄性小鼠进行染毒，5d后用单细胞凝胶电泳技术检测小鼠肝、肾细胞DNA的损伤程度。结果表明，随着纳米TiO2染毒浓度的升高，小鼠肝、肾细胞尾部DNA百分率（Tail DNA％）和尾矩（Tail Moment）均呈逐渐升高趋势；对于肝细胞，0.1mg·mL^-1组Tail DNA％及Tail Moment与对照组无显著差异（p〉0.05），≥0.2mg·mL^-1组则显著升高（p〈0.05或p〈0.01）；与肝细胞相比，肾细胞Tail DNA％及Tail Moment变化更为显著，0.1mg·mL^-1组即与对照组存在极显著差异（p〈0.01）。以上结果表明，纳米TiO2染毒可导致小鼠肝、肾细胞DNA损伤，且随染毒浓度的增加，损伤逐渐加重，呈一定的剂量-效应关系；与肝细胞相比，肾细胞对纳米TiO2更为敏感，较低浓度染毒即可造成DNA损伤。

英文摘要：

To explore the DNA damage effect induced by nano-TiO2 in liver and kidney cells, the anatase TiO2 nanoparticles（20-100nm） were prepared for this experiment. 25 Kunming male mice were exposed to different concentrations of nano-TiO2 （0, 0.1, 0.2, 0.4, 0.8mg·mL^-1）for 5d, and then the single-cell gel electrophoresis was applied to measure the DNA damage. Results demonstrated that with the increase of the nano-TiO2 concentrations, the values of Tail DNA% and Tall Moment of mouse liver and kidney cells were gradually increased. For liver cells, the values of Tall DNA% and Tail Moment of 0.1mg·mL^-1 exposure group had no significant difference with the values of control group （p〉0.05）; but the values of ≥0.2mg·mL^-1 exposure groups were significantly higher （p〈0.05 or p〈0.01 ） than those of control. Compared with liver cells, the changes of Tail DNA% and Tail Moment of kidney cells were more significant, the values of 0.1mg·mL^-1 group even had significant difference with the values of control group （p〈0.01）. Above results suggested that, nano-TiO2 could induce DNA damage of liver and kidney cells, and there was a certain dose-response relationship between the damage and the nano-TiO2 concentrations; kidney cells were more sensitive to nano-TiO2 than liver cells.