醋酸铅染毒小鼠DNA损伤及体内抗氧化酶变化

目的探讨醋酸铅对动物体内DNA的损伤作用、机制以及抗氧化酶的变化情况。方法小鼠经自由饮水，分别给予0，0．196，0．296，0．496醋酸铅染毒6周。采用单细胞凝胶电泳技术对肝细胞DNA损伤进行检测，测定骨髓多染红细胞微核率，同时检测血中血红蛋白（Hb）、肝还原型谷胱甘肽（GSH）含量，以及全血谷胱甘肽过氧化物酶（GSH—Px）和超氧化物歧化酶（SOD）的活性。结果醋酸铅可引起小鼠肝细胞DNA损伤率升高，彗星尾长增加，尾长与头部直径比值（Olive尾矩）增大，同时骨髓嗜多染红细胞微核率增高，均呈明显的剂量一效应关系；同时Hb和肝组织GSH含量降低，全血SOD和GSH—Px活性降低。结论醋酸铅染毒可致小鼠肝细胞和骨髓细胞DNA损伤，体内抗氧化酶活性降低。

DNA damage and changes of antioxidative enzymes in acetate lead poisoned mice

Objective To study the damage effect of lead acetate on DNA and its mechanism and the changes of antioxidative enzymes in vivo.Methods DNA break in liver cell of mice exposed to lead acetate by inhalation at different concentrations for 6 weeks were analyzed with single cell gel electrophoresis(SCGE).Meanwhile,chromatosome damage of bone marrow cell were analyzed with micronucleus test,the activity of superoxide dismutase(SOD),glutathione-Px(GSH-Px) in blood and the level of Hb in blood,glutathione(GSH) in liver were detected.Results At the concentration of 0.1%,0.2%,0.4%,lead acetate could induce DNA damage of liver cells and chromatosome damage of bone marrow cell.Both results showed the obvious dose-response relationship between the level of the genetic materials damage and the doses of lead acetate.Both the activity of SOD,GSH-Px in blood and the level of Hb in blood,GSH in liver were decreased in lead acetate poisoned mice.Conclusion Lead acetate poisoning may result in not only DNA damage in liver cells and chromatosome damage in bone marrow cell,but also decrease in activity of antioxidative enzymes.