Cr3+、Cr6+对鼠肺细胞线粒体膜电位改变及活性氧生成的研究

铬主要以Cr^3 和Cr^6 的形式广泛存在于环境中，其对人或动物的生物效应与其价态有关。本实验用荧光染料罗丹明123和二乙酰二氯氢化荧光素测定细胞内的活性氧和线粒体膜电位，比较Cr^3 和Cr^6 对中国仓鼠肺细胞的毒性作用。发现Cr^3 未引起细胞活性氧生成增加和线粒体膜电位的下降，而Cr^6 可导致细胞活性氧生成增加和线粒体膜电位的下降。提示线粒体可能是Cr^6 所致氧化损伤的靶器官之一，而Cr^6 所致氧化损伤可能是由其诱导产生的ROS介导，而不是由Cr^3 介导。

The Comparison of Chromium(III) and Chromium(VI) Induced Mitochondrial Membrane Potential Dissipation and ROS Formation in CHL Cell Lines

Chromium exists chiefly in two valences: Cr(III) and Cr(VI) in environment. To elucidate the mechanisms of the toxic actions of chromium, we examined the intracellular ROS and mitochondrial membrane potential in CHL cells exposed to Cr(III) and Cr(VI) in use of Rh 123 and 2,7 dichlorofluorescin diacetate. In the present study, we demonstrated that a large amount of ROS was produced and mitochondrial membrane potential decreased in CHL cells exposed to Cr(VI) while there is no statistically significance of production of ROS and decrease of mitochondrial membrane potential found in CHL cells exposed to Cr(III) compared with the control. In conclusion, our study demonstrated that mitochondria may be one of target organelles of oxidative stress caused by Cr(VI). The mechanism of Cr(VI) induced dissipation of membrane potential may involve ROS but not Cr(III) .