镉诱导HL-7702细胞损伤及其机制

目的：探讨镉诱导正常人肝细胞系HL-7702细胞损伤的机制。方法：镉处理组HL-7702细胞暴露于镉浓度分别为5、10、20、30及40 μmol·L^-1RPMI 1640培养液中，另设一对照组。采用生长曲线法，观察不同浓度镉作用1、2、4、6、及8 d对HL-7702细胞增殖的抑制作用；采用MTT法，检测不同浓度镉作用24、48及72 h对HL-7702细胞毒性作用；用PI单染流式细胞术检测不同浓度镉作用24、48及72 h诱导HL-7702细胞周期的改变情况；用AnnexinV-FITC/PI双染流式细胞术检测不同浓度镉作用12、24、48及72 h对细胞凋亡的影响。结果：浓度5~40 μmol·L^-1镉处理组与对照组比较可明显抑制HL-7702细胞生长(P<0.05)，作用48和72 h时细胞发生明显的S期阻滞，作用24、48和72 h均可使细胞发生不同程度的凋亡，72 h时最为明显。结论：镉对HL-7702细胞生长有一定抑制作用，同时镉还可以引起HL-7702细胞发生S期阻滞和细胞凋亡。

Cadmium cytotoxicity on HL-7702 cells and its mechanism

Objective To study the damage effects of different doses of cadmium(Cd~(2+)) on human normal liver cell line HL-7702 cells and its mechanism.Methods HL-7702 cell cultures were exposed to cadmium within a dose range of 5-(40 μmol·L~(-1).) The inhibition of the cells during 8 d was determined by cell counting and the cell growth curve was made.The cytotoxicity of cells during 72 h was determined by MTT assay.Effects of cadmium on the distribution of cell cycle of HL-7702 cells were monitored by flow cytometry analysis(FCM).The apoptotic rate of cells induced by cadmium was determined by Annexin V-FITC/PI double fluorescent staining flow cytometry analysis(FCM) at the same time.Results Cadmium at different concentrations inhibited the growth and proliferation of HL-7702 cells in a dose-dependent manner and the cell growth curve changed accordingly.After treated by different concentrations of cadmium for 24,48 and 72 h,the cell inhibitory rates increased with the elevating of doses.After 48 and 72 h exposure of cadmium,the data showed that certain doses of cadmium might induce S blocking,and this effect was in time-and dose-dependent manner.After 24,48 and 72 h exposure of cadmium,the data suggested that certain doses of cadmium might induce apoptosis.Conclusion Cadmium can significantly inhibit the growth and proliferation of HL-7702 cells and result in S blocking and apoptosis may be responsible for the inhibition.