锌金属硫蛋白对镉致肝肾过氧化损伤的修复作用

Repairing Effects of Zinc-metallothionein on Cadmium-Induced Oxidative Damage of Liver and Kidney in Mice

目的 研究锌金属硫蛋白（ZnMT）对染镉小鼠肝肾过氧化损伤的作用。方法 以昆明种小鼠为研究对象,染镉14d建立铜中毒肝肾损伤动物模型,随后经口灌胃给予ZnMT或ZnSO4 14 d。处死动物,取肝肾组织制作电镜标本,观察肝肾组织形态学变化;测定肝肾组织上清液中脂质过氧化代谢产物——丙二醛（MDA）含量、超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px）活力。结果 给予ZnMT、ZnSO4组实验动物与染镉阳性组比较,其肝肾组织MDA含量降低,SOD、GSH-Px活性均升高,且呈剂量-效应关系。给予ZnMT的实验组动物肝肾组织SOD、GSH-Px活性均较ZnSO4组高,MDA含量则较之低,但两者的差异无统计学意义。结论 ZnMT可对染镉小鼠肝肾组织脂质过氧化损伤起到一定的修复作用。

Objective To study the effects of zinc-metallothionein (ZnMT) on the cadmium-induced oxidative damage of liver and kidney in mice. Methods The model of laboratory animal was established by 14 d-cadmium exposure to Kunming mice. Then the cadmium-poisoning mice were grouped as Cd-ZnMT group and Cd-ZnSO4 group and perfused orally by solution of ZnMT and ZnSO4 for 14 days respectively. The morphological changes of liver and kidney were observed by electron microscope. The contents of malonydiadehyde (MDA), the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in supernatant fluid of liver and kidney were determined. Results The decreases of the contents of MDA, the increases of the activities of SOD and GSH-Px in liver and kidney of mice in Cd-ZnMT and Cd-ZnSO4-exposure group were observed compared with those in cadmium-exposure group, the dose-effect relationships were also found. The increases of the activities of SOD and GSH-Px, the decrease of contents of MDA of liver and kidney, were found in Cd-ZnMT-exposure group compared with those of Cd-ZnSO4-exposure group, but without statistical significances. The morphological damages of liver and kidney observed by electron microscope in mice of cadmium-exposure group were more serious than those in mice treated with solution of ZnMT and ZnSO4 after cadmium exposure. Conclusion ZnMT could repair the lipid peroxidative damages in liver and kidney in mice induced by exposure to cadmium in a certain degree.