姐妹染色单体互换频率影响因素的研究

Research on Incidence of Sister Chromatid Exchange and Its Influencing Factors

[目的]探讨影响姐妹染色单体互换(SCE)频率的因素。[方法]按微量全血培养法,对SCE培养至6h加入5-澳脱氧尿嘧啶核苷(BrdU)后继续培养,对下列3个因素进行研究。①实验条件(a.培养时加入BrdU的浓度:5、10、20、30μg/ml 4个点,b.加BrdU后自然光下曝光时间:0、0.5、30、60及120min 5个点,c.培养时间:56和72h2个点);②接触有害物质因素[接触苯并(a)芘等沥青作业工人34名];③吸烟因素(吸烟者32名)。[结果]①在实验条件中,SCE值随着BrdU浓度的增加而增加,10μg/ml(最佳实验点)和20μg/ml分别为(5.82±1.85)和(6.83±2.37)次/细胞,差异已有显著性(P<0.01);随着曝光时间的延长SCE值亦随之升高,0.5和30min的结果比较差异已有显著性(P<0.01),SCE值分别为(5.88±1.94)和(8.69±2.52)次/细胞,但培养时间对SCE频率无影响;②沥青作业组的SCE值比对照组显著升高,分别为(10.81±1.74)和(6.64±1.52)次/细胞,差异有显著性(P<0.01);③吸烟组的SCE值比非吸烟者(对照组)显著升高,分别为(9.57±1.63)和(6.64±1.52)次/细胞,差异有显著性(P<0.01)。[结论]BrdU浓度、曝光时间、接触某些有害物质作业和吸烟等因素对SCE结果均有较大的影响。

[ Objective ] To investigate the incidence of sister chromatid exchange （ SCE ） and its influencing factors. [ Methods ] The culturing method of whole blood was carded out, then BrdU was added after the samples cultured for 6 hours. Three influencing factors of BrdU was tested as follows： （ 1 ）the experimental environment, including （ a ）the concentrations of BrdU of 5 μg/ml, 10 μg/ml, 20 μg/ml and 30 μg/ml; （ b ） the exposure time of 0 min, 0.5 min, 30 min, 60 min and 120 min; and （ c ） the exposure periods of 56 hours and 72 hours; （ 2 ） the exposure condition, 34 workers exposed to benzo （ a ） pyrene; and （ 3 ） the smoking habit, 32 workers had smoking habit. [ Results ] （ 1 ） The incidence of SCE increased significantly with the concentration of BrdU getting higher, the SCE values of the best（ 10 μg/ml ）and 20 μg/ml resulting concentrations of BrdU were observed to be （ 5.82 ±1.85 ） and （ 6.83 ±2.37 ） times per cell respectively, P 〈 0.01. The SCE values also increased with the exposure time, the value at 0.5 min exposure（ 5.88 ±1.94 ）had significant difference with the value at 30min value（ 8.69 ±2.52 ）, P 〈 0.01, but the exposure time did notaffect SCE frequency apparently. （ 2 ）The SCE values of asphalt workers（ 10.81 ±1.74 ） were significantly higher than that of the control（ 6.64 ±1.52 ）, P 〈 0.01. （ 3 ）The SCE value of smoking group（ 9.57 ±1.63 ）was also significantly higher than that of non-smoking group（ 6.64 ±1.52 ）, P 〈 0.01. [ Conclusion ]It suggests that concentration of BrdU, exposure time, some harmful occupational factors and cigarette smoking habit have obvious effects on results of SCE test.