石棉诱导细胞凋亡改变的研究

目的探讨石棉诱导的细胞凋亡及其相关基因ｂｃｌ２及ｂａｘ表达的改变。方法大鼠石棉染尘。收集石蜡包埋的石棉作业工人肺癌组织块。ＴＵＮＥＬ法（ｔｅｒｍｉｎａｌｄｅｏｘｙｎｕｃｌｅｏｔｉｄｙｌｔｒａｎｓｆｅｒａｓｅｍｅｄｉａｔｅｄｄＵＴＰｎｉｃｋｅｎｄｌａｂｅｌｉｎｇｍｅｔｈｏｄ，末端脱氧核糖核酸转移酶介导的ｄＵＴＰ缺口末端标记法）观察凋亡细胞分布及数量。生物素抗生物素蛋白ＤＣＳ（ａｖｉｄｉｎＤｃｅｌｓｏｒｔｅｒ）间接免疫荧光法观察ｂｃｌ２及ｂａｘ表达改变，琼脂糖凝胶电泳进行ＤＮＡ梯状电泳分析。结果大鼠染尘后４０天，细胞凋亡增强、ｂｃｌ２表达减少、ｂａｘ蛋白含量升高，可见ＤＮＡ特征性梯度电泳条带；大鼠染尘后７０天，细胞凋亡明显减弱。在石棉作业工人肺癌组织中未见明显细胞凋亡。结论石棉可诱导肺组织细胞凋亡发生改变，这种改变有时段性。凋亡相关基因表达也有相应变化。

A study on the asbestosinduced apoptosis

Objective To study the changes of asbestos induced apoptosis and the expression of its related genes,bcl2 and bax. Methods The lung tissue of rats exposed to asbestos and lung cancer tissues of asbestosexposed workers were analyzed.The techniques of TUNEL (the terminal deoxynucleotidyl transferasemediated dUTP nickendlabeling method),biotinavidin DCS system indirect immunofluorescence and agarose electrophoresis were employed. Results In rat lung tissue,apoptosis was enhanced and the expression of bcl2 decreased,but the expression of bax increased on day 40 after dusting.The typical ladder electrophoresis of DNA fragments was observed.On day 70,apoptosis was attenuated.No apoptosis was found in lung cancer tissues of workers exposed to asbestos. Conclusion Asbestos could induce the changes of apoptosis in lung and expression of genes bcl2 and bax at certain period after dusting.