损伤家兔动脉后外膜成纤维细胞增殖、表型变化与TGF-β1表达的关系

Relations between adventitial cell proliferation, phenotype change and transforming growth factor β1 expression after arterial injury in rabbits

目的 :观察损伤家兔动脉后外膜成纤维细胞增殖、表型变化与TGF -β1表达的关系。 方法 :采用免疫组化、透射电镜和原位杂交技术 ,观察兔腹主动脉损伤后外膜细胞增殖、细胞表型、超微结构和TGF -β1mRNA表达水平的变化。结果 :损伤后 3d和 7d血管外膜PCNA阳性细胞显著增多 ,14d接近正常。外膜细胞在损伤后逐渐获得α -actin表达 ,3d呈弱阳性 ,7d和 14d呈强阳性改变。损伤后 7d和 14d外膜细胞发生了显著的超微结构改变 :大量的微丝出现和粗面内质网明显扩张 ,呈现出肌成纤维细胞的特征。损伤后 3d ,外膜开始出现TGF -β1mRNA表达 ,7d和 14d表达持续上调 ,至 2 8d表达开始下调。结论 :提示动脉损伤后外膜成纤维细胞增殖水平和表型变化与TGF

AIM: To investigate the relations between the proliferation and phenotype change of adventitial cells and the expression of T GF-β1 in adventitia after arterial injury. METHODS: After abdominal artery injury in rabbits, adventitial cel l proliferation and phenotype were identified by immunohistochemistry, transmissi on electron microscope and in situ Hybridization. RESULTS: Three days and 7 days after injury, the PCNA-positive ce lls were significantly increased. The previously weakly actin-positive adventiti al cells became strong-actin staining, the typical myofibroblast featurses of ad ventitial cells were detected by TEM 7 and 14 days after injury. Three days afte r vascular injury, there was a marked increase in the nu mber of cells that demonstrated the presence of TGF-β1 transcripts within the adventitia. Seven days after arterial injury, adventitial cells continued to ex press TGF-β1. on day 28, the number of TGF-β1-expressing cells was markedly r e duced in the adventitia. CONCLUSION: This study demonstrates that the proliferation and p henotype modulation of adventitial cells are associated with induction of TGF- β1 expression in adventitia after arterial injury.