氯化镉的体外毒性及锌的拮抗作用

Study on the Cytotoxicity of CdCl_2 in vitro and Antagonism of Zn^(2+) Ion

目的 观察镉与锌体外对中国仓鼠肺成纤维细胞 (V79)增殖的影响 ,初步探讨镉毒性机制。方法 采用MTT法及3 H TdR掺入法 ,研究不同浓度氯化镉 (CdCl2 )单独或与生理浓度氯化锌 (ZnCl2 ,10 μmol/L)同时染毒对V79细胞增殖的影响 ,并采用等离子体光谱仪测定细胞内Cd2 + 、Zn2 + 含量。结果 CdCl2 对于V79细胞的增殖有抑制作用 ,且呈剂量依赖性。采用MTT法和3 H TdR掺入法所得CdCl2 染毒2 4h后 5 0 %抑制浓度 (IC50 )分别为 13 73μmol/L和 13 6 0 μmol/L。随着CdCl2 染毒浓度的增加 ,细胞内Cd2 + 含量也增加。而同时给予锌则对镉的增殖抑制效应在一定程度上具有明显的拮抗作用 ,锌可使细胞内Cd2 + 含量降低。结论 在本实验条件下 ,CdCl2 对V79细胞增殖具有抑制作用 。

Objective To investigate the effect of Cd 2+ and Zn 2+ in the proliferation of Chinese Hamster lung fibroblast cells(V79)in vitro.Methods MTT and 3H-TdR assay were used to detect the effects of CdCl 2 alone and CdCl 2 combined with physiological concentration of ZnCl 2 in cells after treatment.Results CdCl 2 dosage ranging from 5～ 40 μmol/L could inhibit the cellular proliferation effectively after 24 h exposure,the effect showed a dose-dependent manner.The IC 50 of CdCl 2 exposed to V79 for 24 h was 13.73 μmol/L and 13.60 μmol/L by MTT and 3H- TdR incorporation assay respectively.ZnCl 2 can antagonize cells from inhibition of CdCl 2,when it was added to the culture with CdCl 2 simultaneously.It can also inhibit Cd 2+ ion from entering the cells.Conclusions Cd 2+ ion can inhibit the proliferation of V79 cell,while Zn 2+ can antagonize in certain extent.Zn 2+ ion may impair the toxicity of Cd 2+ by interference with the metabolism of Cd 2+.