氯化镉所致DNA损伤及锌的拮抗效应的研究

目的通过体外实验,了解氯化镉(CdCl2)对中国仓鼠肺成纤维细胞(V79细胞)的直接DNA损伤作用及锌的拮抗作用,初步探讨镉的遗传毒性机制及预防措施。方法采用甲基四唑法(MTT法)了解CdCl2对于V79细胞的毒性,通过碱性单细胞凝胶电泳常用的几个评价指标,研究CdCl2体外对于V79细胞DNA的断裂损伤,并采用生理浓度ZnCl2(10μmol/L)加以拮抗。结果MTT试验中,CdCl2对于V79细胞的毒性随染毒剂量增加而增高,呈线性关系,线性方程为:y=-0.009 4x 94.472;在碱性单细胞凝胶电泳中,CdCl2单独染毒,随着染毒剂量增加,DNA损伤加重,而锌具有明显的拮抗作用。结论本实验条件下,CdCl2能造成V79细胞DNA损伤,生理浓度的锌可以拮抗镉的DNA损伤效应。

Study on DNA Damage Induced by CdCl2 in vitro and Antagonistic Effects of Zn Ion

Objective To investigate the effects of Cd~(2 ) and Zn~(2 ) on DNA damage of Chinese hamster lung fibroblast cells(V79)in culture.Methods Methyl tetrazolium test(MTT)assay was used to detect the cytotoxicity of CdCl_2 on V79 cell line.By general indexes of SCGE assay,DNA strand breaks induced by CdCl_2 in vitro on V79 cells and with zinc as antagonizer were observed.Results In MTT test,the cytotoxicity effect of CdCl_2 on V79 raised as the increase in dosage showing linear relationship with the linear equation y=-0.009 4 x 94.472.In alkali SCGE assay,CdCl_2 could damage the DNA of V79 proportionally with the dosages.ZnCl_2 showed obvious antagonistic effect.Conclusions CdCl_2 could induce DNA damage on V79 cells under the experimental condition,while Zn in physiological concentration may antagonize the damage.