中文摘要：

目的观察经60 Coγ射线全胸照射后小鼠肺脏的改变,探究转化生长因子-β3（TGF-β3）在小鼠放射性肺纤维化中的作用。方法180只C57BL/6雌性小鼠随机分为对照组、照射组和TGF-β3组。照射组和TGF-β3组经60 Co γ射线单次全胸照射,照射后每周分别腹腔注射0.5 ml 0.9%生理盐水和TGF-β3（1μg/kg）一次。于照射后3、7、14 d和1、3、6个月活杀,肺脏经HE和天狼星红染色观察病理,检测小鼠肺内循环纤维细胞（ CF）的数量。结果建立小鼠放射性肺纤维化模型。照射后6个月时,TGF-β3组肺脏见点状实变,部分成纤维细胞增生,少量胶原纤维沉积。照射后14 d到6个月,照射组肺脏 CF 数量比对照组明显增加（ P 〈0.05）。照射后1个月时,TGF-β3组肺脏CF数量比照射组明显减少（ P〈0.05）。结论 TGF-β3使CF在肺内的聚集明显减少,其可能在延缓肺纤维化发生过程中发挥重要作用。

英文摘要：

Objective To observe the changes of lungs in mice after 60 Co γ-ray irradiation on whole breast,and to explore the role of TGF-β3 in radiation-induced pulmonary fibrosis in mice. Methods 180 C57BL/6 female mice were randomly divided into control group,irradiation group and TGF-β3 group. The mice in irradiation group and TGF-β3 group were irradiated once by 60 Coγ-ray with does of 20 Gy on whole chest. Then,the mice of both groups above were intraperitoneal injected 0. 9% saline and TGF-β3 （1 μg/kg） 0. 5 ml respectively once a week. Kill the mice at 3,7,14 days and 1,3,6 months after irradiation. To observe pathology of lungs by HE staining and Sirius red staining,and to detect the number of CF in lungs of mice. Results To establish the model of radiation-induced pulmonary fibrosis in mice. 6 months after irradiation,the lungs in TGF-β3 group appeared proliferation of some fi-broblasts and deposition of a small amount collagen. From 14 days to 6 months after irradiation,the number of CF in lungs in irradiation group was significantly higher（P〈0.05） than control group. 1 month after irradiation,number of CF in lungs in TGF-β3 group was significantly lower （ P〈0.05 ） than irradiation group. Conclusion TGF-β3 obviously reduces the accumulation of CF in lungs of mice after radiation,which may play an important role in dela-ying the occurrence of pulmonary fibrosis.