Lepistö J, Peltonen J, Vähä-Kreula M, Söderström K, Niinikoski J, Laato M
Department of Surgery, University of Turku, FIN-20520 Turku, Finland.
Cell Tissue Res. 1996 Dec;286(3):449-55. doi: 10.1007/s004410050714.
Subcutaneous sponges in rat were used as a wound model to study the changes in collagen gene expression induced by different isoforms of platelet-derived growth factor (PDGF). The steady state levels of proalpha1(I) and proalpha1(III) collagens rose markedly in response to PDGF-AB treatment. In marked contrast to PDGF-AB, PDGF-BB exerted a down-regulatory effect on the expression of type I and III procollagen mRNA levels. In situ hybridisation signal for proalpha1(I) collagen mRNA was most prominent in the periphery of the sponges in response to PDGF-AB. In PDGF-AA and PDGF-BB treated sponges, however, the hybridisation signal for proalpha1(I) collagen mRNA was evenly distributed. Immunolabellings demonstrated the presence of type I and III collagen epitopes and thus revealed the deposition of these proteins into developing granulation tissue. The volume of ingrown granulation tissue was estimated by measuring the cross-sectional area of the samples. PDGF-AB and PDGF-BB were both effective resulting in a significant increase in the amount of granulation tissue. However, only a limited enhancement of granulation tissue ingrowth was observed in response to PDGF-AA treatment. To conclude, PDGF-AB and PDGF-BB induced significantly the ingrowth of repair tissue in wounds. PDGF-AB distinctively upregulated collagen gene expression, while PDGF-BB primarily seemed to be mitogenic.
将大鼠皮下海绵作为伤口模型，以研究血小板衍生生长因子（PDGF）不同亚型诱导的胶原基因表达变化。PDGF-AB处理后，前α1（I）和前α1（III）胶原的稳态水平显著升高。与PDGF-AB形成鲜明对比的是，PDGF-BB对I型和III型前胶原mRNA水平的表达具有下调作用。响应PDGF-AB时，前α1（I）胶原mRNA的原位杂交信号在海绵周边最为明显。然而，在PDGF-AA和PDGF-BB处理的海绵中，前α1（I）胶原mRNA的杂交信号分布均匀。免疫标记显示存在I型和III型胶原表位，从而揭示了这些蛋白质在发育中的肉芽组织中的沉积。通过测量样品的横截面积来估计内生肉芽组织的体积。PDGF-AB和PDGF-BB均有效，导致肉芽组织数量显著增加。然而，响应PDGF-AA处理时，仅观察到肉芽组织向内生长的有限增强。总之，PDGF-AB和PDGF-BB显著诱导伤口修复组织向内生长。PDGF-AB显著上调胶原基因表达，而PDGF-BB主要似乎具有促有丝分裂作用。
