中文摘要：

目的用γH2AX识别抗体流式细胞术研究铅暴露致人体外周血淋巴细胞DNA双链断裂（DSBs）作用。方法选取某蓄电池厂工人36人为铅接触组，其中高浓度组15人，低浓度组21人；同时选择厂外无职业性铅接触70人为对照组，取外周静脉血提取淋巴细胞，利用流式细胞术检测γH2AX，分析淋巴细胞中DNADSBs水平；不同剂量、时间下醋酸铅染毒健康人外周血淋巴细胞，利用流式细胞术检测γH2AX,分析淋巴细胞中DNADSBs水平。结果高浓度铅接触组DNA损伤率和平均荧光强度分别为41．76％±28．57％、9．90±3．35，低浓度铅接触组分别为33．18％±30．64％、9．39±4．83，均高于对照组（分别为0．28％±0．28％、6．95±2．93），差异均有统计学意义（P〈0．05）。体外试验结果显示，染毒1和2h时，除62．5μmol／L外，125．0、250．0、500．0μmol，L醋酸铅染毒组DNA损伤率与阴性对照组的差异均有统计学意义（P〈0．01）。随着染毒剂量的增高，DNA损伤率呈现先增高后降低的趋势。结论铅可致人淋巴细胞DNADSBs，流式细胞术检测γH2AX是一种值得运用于检测大样本DNADSBs水平的方法。

英文摘要：

Objective To study DNA double-strand breaks of human peripheral lymphocytes exposed to lead with flow cytometry （FCM）. Methods The lymphocytes were obtained from 36 workers occupationally exposed to lead and 70 residents without occupational exposure to lead. DNA double-strand breaks were detected by flow cytometer assay. The lymphocytes from health people were incubated with lead at different doses and time, FCM assay was used to detect DNA double-strand breaks. Results DNA double-strand breaks and fluo- rescence intensity of high exposed group and low exposed group were 41.76%±28.57%, 9.90±3.35 and 33.18%-± 30.64%, 9.39±4.83, respectively, which were significantly higher than those （0.28%±0.28% and 6.95±2.93） of control group （P〈0.05）. The results of in vitro experiment indicated that DNA double-strand breaks of lympho- cytes exposed to Pb at the dose of 125.0, 250.0, 500.0 μmol/L for 1 and 2 h were significantly different from those of the negative control group and positive control group （P〈0.01）. DNA double-strand breaks increased at beginning and then decreased with lead doses. Conclusion Lead can induce DNA double-strand breaks, γH2AX detected using flow cytometer assay can be used to measure the DSBs of DNA in large samples.