【作者】 孔席丽；

【导师】 郑玉建； 杨晓燕； 吴顺华；

【作者基本信息】 新疆医科大学 ， 劳动卫生与环境卫生学， 2008， 硕士

【摘要】 目的:研究亚砷酸钠(NaAsO2)对正常人淋巴细胞活力的影响,观察砷对抗氧化物质及抗氧化酶的作用,探讨砷对过氧化氢酶(CAT)的RNA表达的影响。方法:不同浓度的NaAsO2(2、5、10、15、30、60μmol/L)作用于淋巴细胞24h,48h,72h,用四噻唑兰(MTT)还原法观察淋巴细胞生长情况;采用酶联免疫吸附法(ELISA)检测淋巴细胞中谷胱甘肽(GSH)含量、黄嘌呤氧化酶法检测超氧化物歧化酶(SOD)活力、硫代巴比妥法(TBA)检测丙二醛(MDA)含量、紫外分光法检测CAT活力。NaAsO2作用淋巴细胞72h后,用逆转录-聚合酶链反应(RT-PCR)检测CAT的RNA表达水平。结果:1.与对照组相比,2、5μmol/L染毒组淋巴细胞活力增强,10μmol/L以上染毒组淋巴细胞活力降低,且存在时间-剂量交互效应(F=2.023,P<0.05);2. 2～10μmol/L染毒组淋巴细胞GSH含量增加,GSH含量在24、48、72h明显高于对照组(P<0.05),SOD活力提高、MDA含量降低、CAT活力提高;与2、5μmol/L染毒组比较,15～60μmol/L染毒组淋巴细胞GSH含量降低,SOD活力降低,MDA含量增加、CAT活力降低,各染毒组在24hCAT含量差异均有统计学意义(P<0.05),且存在时间-剂量交互效应(F分别为12.382,4.212,3.498,2.149,P均<0.01);3. GSH含量和SOD活力之间存在正相关性(r=0.977,P<0.01),与MDA含量之间存在负相关性(r=-0.956,P<0.01),SOD活力和MDA含量之间存在负相关性(r=-0.924,P<0.01);4. CAT活力和GSH含量(r=0.784,P =0.000)、SOD活力(r=0.765,P=0.000)之间存在正相关性,并和MDA含量(r=-0.814,P=0.000)之间存在负相关性;5. RT-PCR电泳结果可见,2~10μmol/L染毒组淋巴细胞CAT/β-actin吸光度比值与对照组比较轻微上升,15~60μmol/L染毒组淋巴细胞CAT/β-actin吸光度比值与对照组比较明显下降,且呈剂量-反应关系。结论:15μmol/L以上NaAsO2可降低淋巴细胞内CAT基因的RNA表达水平并可抑制淋巴细胞生长,砷通过降低抗氧化物质含量、抗氧化酶活力,诱导抗氧化基因表达下调,引起抗氧化反应水平增高。CAT的诱导下降与地方性砷中毒易感性有关,可以考虑作为地方性砷中毒易感标志物。更多还原

【Abstract】 Objective: To investigate the effects of sodium arsenic(NaAsO2) on human lymphocyte cells activities,anti-oxidation system and RNA of CAT. Methods: Lymphocyte were incubated with NaAsO2 in different does for 24h,48h,72h.MTT reduction assay was used to observed cells activities.Glutathion(GSH), Superoxid(SOD),Malondialdehyde (MDA) were measured and analyzed by enzyme linked immuno- absorbent assay. Catalase(CAT) was measured by ultraviolet spectrometry. RT-PCR was used to detect the RNA expression of CAT. Results:1. Compared with the control group, when the cells were in 2,5μmol/L NaAsO2 groups, the activity of lymphocytes increased, and in the does of higher than 10μmol/L groups,the activity of lymphocyte decreased;2. When the cells were in 2～10μmol/L NaAsO2 groups, the level of GSH and the activity of SOD and CAT increased significantly.While the level of MDA decreased significantly. Moreover,in high does groups(15～60μmol/L) , the results were oppositive,and showed a interaction of time and does;3. GSH has positively correlation to SOD(r=0.977 , P < 0.01)and negatively correlation to MDA(r=-0.956 , P < 0.01), meanwhile,MDA has negatively correlation to SOD(r=-0.924,P<0.01);4. CAT has positively correlation to GSH(r=0.784,P =0.000) and SOD(r=0.765 , P=0.000).CAT has negatively correlation to MDA(r=-0.814,P=0.000).5. If the cells were treated with 2~10μmol/L sodium arsenite,RNA of CAT were up regulated,and if the cells were treated with 15~60μmol/L sodium arsenite,RNA of CAT were down regulated and and in a doesge dependent fashion. Conclusions: This study suggests that the lymphocyte activities can be inhibited and the level of mRNA of CAT was decreased by NaAsO2 in the does higher than 15μmol/L.Arsenic can increase the level of aiti-oxidation action by decreasing the levles of anti-oxidation matarial and the activities of antioxidase. Catalase may influence the risk of arsenism. Catalase can be considered as endemic arsenic susceptibility markers.更多还原