关键词: 转化生长因子β, 肺纤维化, 免疫组织化学

Abstract: To study the expressions of IGF-Ⅰ and TGF-β₁　in lung tissue of rats with pulmonary fibrosis. Methods Sixty male Wistar rats were randomly divid ed into two groups: control group (n=20) and experimental group (n=40), and poured respectively by saline and bleomycin solutions, and killed on the 7th, 14th, 21th, 28th day. Immunohistochemistry method was used to analyze the expressions of IGF-Ⅰ and TGF-β₁ in lung tissue. Results After 4 weeks induction by bleomycin solutions, the lung tissue was obtained and stained by HE, the pathological changes were in accordance with pulmonary fibrosis. Pulmonary interstitial fibers were found by VG staining. So lung fibrosis models induced by bleomycin were set up successfully. The expressions of IGF-Ⅰ and TGF-β₁ were increased during the progression of pulmonary fibrosis. Excellent differences of percentage of positive cells and expression level of IGF-Ⅰ and TGF-β₁ were found between control group and experimental group（P<0.05).The expressions of IGF-1 were increased on the first, second, and third week, and decreased on the fourth week, however, there were excellent differences between the first and third week and between the first and fourth week（P<0.05）. The peak of TGF-β₁ expression was on the second week, and decreased during the third week. But its expression on the fourth week was also higher than that on the first week. Excellent differences were found between the first week and the second or third week（P<0.05）. Conclusion The high level expressions of IGF-Ⅰand TGF-β₁ have the vital significance for the formation of pulmonary fibrosis, both IGF-Ⅰ and TGF-β₁ also take an effect on the pulmonary fibrosis formation, and may have synergetic effect.

Key words: transforming growth factor beta, pulmonary fibrosis, immunohistochemistry