目的:探讨PDGF/Rock通路介导的肌成纤维细胞分化在大鼠矽肺纤维化形成中的作用。方法:采用非暴露式气管二氧化硅混悬液灌注法制备大鼠矽肺模型,SPF级健康成年Wistar大鼠40只随机分为四组:模型对照4周组、模型对照8周组、矽肺模型4周组、矽肺模型8周组,每组10只。Western blot检测肺组织内α-SMA、phospho-PDGF-β、ROCK、Ⅰ型和Ⅲ型胶原蛋白的表达。结果:大鼠矽肺模型制备成功。与相应对照组相比,矽肺模型组大鼠肺组织内α-SMA、phospho-PDGFR-β、Rock以及Ⅰ型和Ⅲ型胶原蛋白表达均明显增加,比较差异有统计学意义(P〈0.05)。结论:PDGF介导的ROCK信号转导通路可能通过促进大鼠肌成纤维细胞转化而促进矽肺大鼠肺组织内的胶原合成,进而促进矽肺纤维化的形成。
Objective:To investigate the role of myofibroblast’s differentiation mediated by PDGF/Rock pathway in the pathogenesis of pulmonary fibrosis.Method:SiO2 powders were douched in bronchial tube of rat to make the silicotic model. Fourty Wistar rats were randomly divided into 4 groups,including normal control 4 weeks group,normal control 8 weeks group,silicosic model 4 weeks group,silicosic model 8 weeks group.The expression and distribution of phospho-PDGFR-β were observed by immunocytochemistry.Expressions of α-smooth muscle actin (α-SMA),phospho-PDGFR-β,Rock, collagenⅠand collagen Ⅲ were detected by Western blot.Result:Model of rats with silicosis was successful established.Compared with the corresponding control groups,the expressions of α-SMA,phospho-PDGFR-β,ROCK,type Ⅰand type Ⅲ collagen in pulmonary tissues of silicosic model groups increased significantly (P〈0.05).Conclusion:PDGF/Rock pathway may play an important role in the development of silicosis by promoting myofibroblast differentiation and further secreting more collgen.