中文摘要：

目的探索金属离子铅对K562细胞红系分化能力的影响。方法应用胎盼蓝染色排除法分析铅离子对K562细胞的活性的影响;用联苯胺染色法检测铅离子作用下K562细胞的红系分化率;利用荧光标记抗体结合流式细胞技术分析铅离子处理K562细胞的细胞表面转铁蛋白受体CD71的表达。结果铅离子（10～50μmol/L）分别作用24、48和72 h对K562细胞生长有浓度依赖性的抑制作用;铅离子（10～30μmol/L）作用48 h对氯化高铁血红素诱导的K562细胞血红蛋白合成表现出较为明显的浓度依赖性抑制;铅离子（30μmol/L）作用48 h可一定程度地上调CD71在细胞表面的表达。结论铅离子在一定的浓度作用下对K562细胞的诱导红系分化有抑制作用,为进一步应用K562细胞研究铅离子的红系血液毒性的细胞分子机制提供了一定的实验依据。

英文摘要：

Objective The effect of lead acetate on the erythroid differentiation of K562 cells was investigated.Method Survival rate of cells was determined by trypan blue staining.The percentage of cells containing hemoglobin was estimated by staining with benzidine.The expression of transferrin receptor CD71 on the surface of K562 cells was estimated by flow cytometry after staining with FITC-conjugated anti-CD71 antibody.Results After the K562 cells were treated with Pb（10-50 μmol /L） for 24,48,or 72 h,the K562 cells growth showed a concenration-dependent inhibition.When K562 cells were exposed to Pb（10-30 μmol /L） for 48 h,the hemin-induced hemoglobin synthesis showed an obvious concentration-dependent inhibition.Exposure to lead ions（30 μmol /L） for 48 h caused an up-regulation of CD71 protein on the cell surface.Conclusion The lead acetate could inhibit hemin-induced erythroid differentiation of the K562 cells,suggesting that K562 cells could be used as a in vitro model to research the mechanisms of the erythropoietic toxicity of lead.