肺纤维化形成过程中大鼠成纤维细胞对肺泡Ⅱ型上皮细胞的影响

Effects of Pulmonary Fibroblasts on Type Ⅱ Alveolar Epithelial Cells in the Rat Model of Pulmonary Fibrosis Induced by Pingyangmycin

目的:研究在平阳霉素诱导的大鼠肺纤维化形成过程中肺成纤维细胞对肺泡Ⅱ型上皮细胞的影响。方法:先将大鼠分成平阳霉素组和生理盐水组,平阳霉素组气管内给药复制大鼠肺纤维化动物模型(平阳霉素3mg/kg),生理盐水组气管内注射等量生理盐水,分别于7,28 d处死平阳霉素组大鼠10只,生理盐水组大鼠4只,其中平阳霉素组及生理盐水组各取3只提取肺成纤维细胞,平阳霉素组6只提取大鼠原代Ⅱ型肺泡上皮细胞,分别进行培养。待两种细胞均已贴壁后,再进行如下分组即:①实验组:用平阳霉素组肺成纤维细胞上清液加入平阳霉素组肺泡Ⅱ型上皮细胞并培养48 h;②对照组:用生理盐水组肺成纤维细胞上清液加入平阳霉素组肺泡Ⅱ型上皮细胞并培养48 h。用半定量RT-PCR法检测实验组和对照组中肺泡Ⅱ型上皮细胞SP-A、TGF-β及HGF mRNA表达的变化。结果:①SP-A mRNA和HGF mRNA的表达实验组低于对照组(P<O.05).且7 d高于28 d;②TGF-βmRNA的表达实验组明显高于对照组(P<0.05),7 d高于28 d。结论:在肺纤维化的形成过程中,肺成纤维细胞影响了肺泡Ⅱ型上皮细胞的增殖修复。

Objective： To investigate the effect of pulmonary fibroblasts on type Ⅱ alveolar epithelial cells in the rat model of Pingyangmycin induced pulmonary fibrosis. Methods： Twenty-eight SD rats were randomly divided into Pingyangmycin group and normal saline group. Pulmonary fibrosis was induced by intratracheal instillation with Pingyangmycin or normal saline in the two groups. Then ten rats in the Pingyangmycin group and four rats in the normal sodium group were sacrificed respectively on the 7th and 28th day after the intratracheal instillation. Pulmonary fibroblasts were abstracted respectively from three sacrificed rats respectively in Pingyangmycin group and normal saline group. Meanwhile, type Ⅱ alveolar epithelial cells were abstracted from six sacrificed rats in the Pingyangmycin group. Then the supernate of pulmonary fibroblasts from Pingyangmycin group and from normal saline group were respectively added into the type Ⅱ alveolar epithelial cells in Pingyangmycin group, and the cells were co-cultured for 48 hours.The levels of SP-A mRNA, TGF-β mRNA and HGF mRNA of Ⅱ alveolar epithelial cells were detected by semi-quantitate RT-PCR. Results： The levels of SP-A mRNA and HGF mRNA in the experiment group （type Ⅱ alveolar epithelial cells＋ Pingyangmycin induced pulmonary fibroblasts） were lower than those in the control group （type Ⅱ alveolar epithelial cells ＋ normal saline induced pulmonary fibroblasts） （both P〈0.05） ,and the level of TGF-β mRNA in the experiment group was higher （P〈0.05）. Conclusion： Pulmonary fibroblasts can impact the generation and recovery of type Ⅱ alveolar epithelial cells in the procession of pulmonary fibrosis.