Floege J, Hudkins K L, Seifert R A, Francki A, Bowen-Pope D F, Alpers C E
Division of Nephrology, Medical School, Hannover, Germany.
Kidney Int. 1997 Apr;51(4):1140-50. doi: 10.1038/ki.1997.157.
Using in situ hybridization and immunocytochemistry we describe the renal localization of the PDGF alpha-receptor. PDGF alpha-receptor mRNA was uniformly present in human metanephric kidney in interstitial cells and vascular arcades that course through the blastema. PDGF alpha-receptor mRNA was present in some mesangial structures in early glomeruli, but was largely lost as glomeruli matured. It was present in adventitial fibroblasts, but usually not in vascular smooth muscle cells or endothelial cells of the fetal vasculature. This pattern persisted in adult kidneys, with extensive expression of mRNA by interstitial cells and only occasional expression by mesangial cells. All in situ hybridization findings were corroborated by immunocytochemistry. Double immunolabeling confirmed the rare expression of the PDGF alpha-receptor protein by vascular smooth muscle cells and the absence of its expression by endothelial cells. Given that both PDGF A- and B-chain can promote smooth muscle cell and fibroblast migration and proliferation and that both signal through the PDGF alpha-receptor, these data suggest that PDGF alpha-receptor may play important roles in the early vasculogenesis of the fetal kidney as well as in the pathogenesis of renal interstitial fibrosis.
我们运用原位杂交和免疫细胞化学技术描述了血小板源性生长因子α受体（PDGFα受体）在肾脏中的定位。PDGFα受体mRNA在人后肾间质细胞以及穿过胚基的血管弓中均有一致表达。PDGFα受体mRNA在早期肾小球的一些系膜结构中存在，但随着肾小球成熟大部分消失。它在外膜成纤维细胞中存在，但在胎儿血管的血管平滑肌细胞或内皮细胞中通常不存在。这种模式在成年肾脏中持续存在，间质细胞广泛表达mRNA，而系膜细胞仅偶尔表达。所有原位杂交结果均得到免疫细胞化学的证实。双重免疫标记证实血管平滑肌细胞中PDGFα受体蛋白表达罕见，内皮细胞中无该蛋白表达。鉴于PDGF A链和B链均可促进平滑肌细胞和成纤维细胞迁移及增殖，且二者均通过PDGFα受体发出信号，这些数据表明PDGFα受体可能在胎儿肾脏早期血管生成以及肾间质纤维化发病机制中发挥重要作用。
