Han R N, Mawdsley C, Souza P, Tanswell A K, Post M
Department of Paediatrics, Hospital for Sick Children Research Institute, Toronto, Ontario, Canada.
Pediatr Res. 1992 Apr;31(4 Pt 1):323-9. doi: 10.1203/00006450-199204000-00004.
To further study the role of platelet-derived growth factor (PDGF) in fetal lung development, the distribution of the PDGF homodimers PDGF-AA and PDGF-BB was examined by immunohistochemistry in embryonic and fetal rat lung from d 12 to 22 of gestation (term = 22 d). PDGF-AA and PDGF-BB were localized to airway epithelial cells as early as d 12 of gestation, 2 d before their appearance in mesenchymal cells. Both PDGF homodimer immunoreactivities increased until the late pseudoglandular stage of lung development, followed by fluctuations in reactivity during the canalicular stage. Only weak immunoreactivity to either PDGF homodimer was evident during the saccular stage of lung development. Immunodetection by Western blotting revealed that PDGF-AA and PDGF-BB homodimer protein concentrations were high during the embryonic and pseudoglandular stage of lung development and decreased with advancing gestation. We conclude that the presence of PDGF in both developing airway epithelial cells and mesenchymal cells, as well as gestation-dependent changes of PDGF homodimers, is compatible with a role for this growth factor during fetal lung development.
为进一步研究血小板衍生生长因子（PDGF）在胎肺发育中的作用，采用免疫组织化学方法检测了妊娠12至22天（足月为22天）胚胎和胎鼠肺中PDGF同型二聚体PDGF-AA和PDGF-BB的分布。早在妊娠12天，即PDGF-AA和PDGF-BB出现在间充质细胞的2天前，它们就定位于气道上皮细胞。两种PDGF同型二聚体的免疫反应性在肺发育的假腺泡晚期之前均增加，随后在小管期反应性出现波动。在肺发育的囊状期，仅对两种PDGF同型二聚体有微弱的免疫反应。蛋白质印迹免疫检测显示，PDGF-AA和PDGF-BB同型二聚体蛋白浓度在肺发育的胚胎期和假腺泡期较高，并随妊娠进展而降低。我们得出结论，发育中的气道上皮细胞和间充质细胞中均存在PDGF，以及PDGF同型二聚体的妊娠依赖性变化，这与该生长因子在胎肺发育中的作用是相符的。
