锌对镉致淋巴细胞DNA损伤的保护作用

目的探讨锌对镉致淋巴细胞DNA损伤的保护作用。方法小鼠经腹腔同时注射1．25，2．50，5．00mg／kg硫酸锌和2．50mg／kg氯化镉水溶液，染毒24h和48h后分别取外周血和胸腺，采用单细胞凝胶电泳（singlecell gel eletrophoresis，SCGE）技术观察不同浓度锌对镉致小鼠外周血和胸腺淋巴细胞DNA损伤的保护作用。结果与阴性对照组比较，镉组的淋巴细胞DNA平均迁移长度明显增加，且差异有显著性（P〈0．05）。不同剂量的锌和镉同时作用时，无论染毒24h还是48h，外周血和胸腺淋巴细胞的DNA平均迁移长度明显下降，与镉组比较，差异有显著性（P〈0．05）。结论锌对镉致淋巴细胞DNA损伤有保护作用。

Protective Effect of Zinc on Cadmium Induced DNA Damage in Lymphocytes

Objective To study the protective effect of zinc on cadmium induced DNA damage in lymphocytes.Methods Mice were injected intraperitoneally with water solution of zinc sulfate by different dose(1.25,2.50,(5.00 mg/kg))and cadmium chloride(2.50 mg/kg)simultaneously.After exposing 24 h and 48 h,the peripheral blood and thymus were obtained and the single cell gel eletrophoresis(SCGE)was used to study the protective effect of different doses of zinc on cadmium-induced DNA damage in mouse peripheral lymphocytes and thymus lymphocytes.Results The average length of DNA migration of cadmium group was significantly higher than that of control group(P<0.05).Varied dose of zinc and cadmium exposed simultaneously for(24 h) or(48 h),the average length of DNA migration of peripheral lymphocytes and thymus lymphocytes decreased significantly compared to cadmium group(P<0.05).Conclusions The results suggest that zinc has a protective effect on cadmium induced DNA damage in lymphocytes.