铀矿尘致大鼠肺纤维化中转化生长因子β1的表达

Expression of Transforming Growth Factor β1 in Pulmonary Fibrosis Induced by Uranium Mineral Dust

目的探讨铀矿尘诱导肺组织纤维化过程转化生长因子-β1(TGF-β1)在肺组织中的表达以及TGF-β1含量的变化。方法36只大鼠随机等分为铀矿尘组和对照组。采用一次性非暴露式气管内滴注染尘方法,铀矿尘组每只大鼠气管内滴注20mg/ml的粉尘悬液1ml,对照组气管内滴注生理盐水1ml,分别于处理后第14、30d及60d每组随机处死6只取样,观察肺组织病理形态改变以及肺组织中TGF-β1的表达,测定肺匀浆和血浆中TGF-β1含量的改变。结果铀矿尘组在染尘后第14d时肺组织主要表现为炎症改变,第30d时出现纤维增生同时TGF-β1表达增强,第60d时表现为大量的纤维增生并伴有TGF-β1强表达。肺匀浆和血浆中TGF-β1含量在第14d时高于对照组,第30d及60d时肺匀浆和血浆中TGF-β1含量显著高于对照组(P<0.01)。结论铀矿尘诱导肺组织纤维化过程中存在TGF-β1高表达,肺匀浆和血浆中TGF-β1含量明显增加。

Objective To explore the expression of transforming growth factor β1 （TGF-β1） in pulmonary fibrosis induced by uranium mineral dust as well as the changes of TGF-β1 levels in lung homogenate and plasma.Methods Thirty-six rats were randomly divided into uranium dust group and control group.Non-exposed endotracheal instillation method was used.Each rat in uranium ore dust group was intratracheally instilled with uranium dust suspension （1 ml,20 mg/ml）,and each rat in control group was intratracheally instilled with normal saline （1 ml）.Six rats in each group were randomly sacrificed on the 14th,30th,and 60th post-exposed days,the pathological changes in lung tissue were observed and TGF-β1 levels in lung homogenate and plasma were measured.Results The main manifestation in lung tissue was the inflammation on the 14th exposed day.Fibrosis in lung matrix and expression of TGF-β1 were simultaneously increased on the 30th exposed days.A large number of fiber hyperplasia was accompanied with high expression of TGF-β1 on the 60th exposed days.At the 14th day,TGF-β1 levels in the lung homogenate and plasma of uranium dust group were higher than those of control group,and the TGF-β1 levels on the 30th and 60th days were significantly higher than those of control group （P0.01）.Conclusions High expression of TGF-β1 exists in the process of pulmonary fibrosis induced by uranium dust,and TGF-β1 levels in lung homogenate and plasma are increased significantly.