【摘要】 目的探讨二氧化硅（SiO₂）体内体外影响人肺成纤维细胞α-平滑肌肌动蛋白（α-SMA）的表达情况。方法体内实验以SiO₂灌注的大鼠矽肺模型为研究对象,实验组32例（7、14、21和28d各8例）,对照组32例。免疫组化法检测肌成纤维细胞标志物α-SMA的表达；体内实验以人肺成纤维细胞（HiF-02）为研究对象,分别用SiO₂刺激的体外小鼠腹腔巨噬细胞系（RAW264．7细胞）上清液、SiO₂未刺激的RAW264．7细胞上清液、SiO₂悬液以及转化生长因子β₁（TGF-β₁）作用24h,免疫印迹法检测α-SMA的表达变化情况。结果（1）染尘28d大鼠肺组织有表达α-SMA阳性的肌成纤维细胞出现。（2）HAW264．7细胞上清液（SiO₂）可诱导HLF-02细胞α-SMA的表达,而TGF-β₁可明显上调α-SMA表达。（3）单纯SiO₂悬液对HLF-02细胞α-SMA的表达没有影响。结论肌成纤维细胞与矽肺纤维化进展有关；体外条件下肌成纤维细胞的出现不是SiO₂直接作用的结果,而与SiO₂活化巨噬细胞分泌的介质TCF-β₁有关。更多还原

【Abstract】 Objective To investigate the effects of SiO₂ on the expression ofα-smooth muscle actin （α-SMA）in haman lung fibroblasts in vitro and vivo.Methods The experimental group comprised 32 rats while 32 rats were includedin the control.In vivo,the expression ofα-SMA in lung tissues of rats exposed to SiO₂,the su- pernate of RAW264.7 cells,SiO₂ and the growth factorβ₁（TGF-β₁）were investigated,respectively.Results （1）α-SMA positive myofibroblasts appeared in the lung tissues of the 28th day groups exposed to SiO₂.（2）The expres- sion ofα-SMA in HLF-02 cells was unregulated by TGF-β₁ and supernate of RAW264.7 ceils exposed to SiO₂.（3） The expression ofα-SMA in HLF-02 cells was not induced by SiO₂.Conclusion Myofibroblasts related to silico- sis,and the appearance of myofibroblasts（in vitro）are independent on direct stimulation by SiO₂,but related to the mediator（TGF-β₁）secreted by SiO₂ stimulated macrophages.更多还原