【摘要 】 目的 观察博莱霉素致肺纤维化大鼠肺泡II型上皮细胞肿瘤坏死因子(TNFα)和血小板衍化生长因子(PDGF)表达的变化。方法 大鼠气管内灌注博莱霉素A₅ 复制肺纤维化模型，分别于注药后第3、7、14和28天处死动物，进行免疫组织化学染色；同时提取肺泡Ⅱ型上皮细胞总RNA进行Northern杂交。结果 正常大鼠肺泡Ⅱ型上皮细胞不表达TNFα和PDGF；而肺纤维化大鼠肺泡Ⅱ型上皮细胞则表达TNFα和PDGF。其中TNFα表达高峰在注药后第28天；PDGF的表达高峰在注药后第7天。结论 肺纤维化大鼠肺泡Ⅱ型细胞过度表达TNFα和PDGF，参与了肺纤维的发病过程。

Song Mingchen,He Bing,Qiu Zhongmin, et al, Division of Respiratory Medicine,The First Hosipital of Beijign MedicalUniversity, Beijing 100034

【Abstract 】 Objective The expressions of TNF α and PDGF in alveolar type Ⅱ epithelial cells of rats with bleomycin(BLM)-induced pulmonaryfibrosis were studied. Method A single intratracheal injection of BLM was administrated to inducepulmonary fibrosis of rats. Animals were killed at day 3,7,14and 28 afterBLM-administration.The immunohistochemical methods were used to analyze the expressions ofTNFα and PDGF proteins in alveolarepithelium of rats.The total RNA was extracted from the alveolar type Ⅱepithelial cells of rats and the expressions of TNF α and PDGFmRNA were analyzed with Northern blot. Result TNF α andPDGF were expressed in the alveolar typeⅡepithelialcells of BLM-administrated rats.The expression of TNFα elevated in median and late-stage of the process and reached thepeak at day 28. While the expression of PDGF elevated in early-stage and reached the peakat day 7. By contrast, TNF α and PDGFweren't expressed in the alveolar type Ⅱepithelialcells of normal controls. Conclusion Theresults show that the alveolar type Ⅱ epithelialcell from rats with pulmonary fibrosis overexpresses TNF α and PDGF and they may play roles in the pathogenesis of lungfibrosis.

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