Cai Y, Han M, Luo L, Song W, Zhou X
Department of Physiology, Institute of Basic Medical Sciences, CAMS, Beijing.
Chin Med Sci J. 1996 Sep;11(3):152-6.
The role of growth factors and proto-oncogene in pulmonary vascular structural remodelling is not well known. The present study examined gene expression of platelet-derived growth factor (PDGF)-A and -B chain and proto-oncogene, c-myc, in lung tissue and pulmonary artery of rats exposed to hypoxia and compared to those levels of gene expression in normal rats. Normal lungs and pulmonary artery expressed PDGF-A chain transcript of 1.7 kb and PDGF-B chain transcript of 3.5 Kb. The c-myc transcript of 2.2 kb was expressed as well. After hypoxic exposure for 7 and 14 days mRNA levels of PDGF-B chain and c-myc were elevated significantly compared with those of control rats. PDGF-A chain mRNA increased after hypoxia for 7 days, and then declined. These results suggest that activation of autocrine and/or paracrine is important in proliferation mechanism of pulmonary artery smooth muscle cells in hypoxic pulmonary hypertensive rats.
生长因子和原癌基因在肺血管结构重塑中的作用尚不明确。本研究检测了暴露于低氧环境的大鼠肺组织和肺动脉中血小板衍生生长因子（PDGF）-A链和-B链以及原癌基因c-myc的基因表达，并与正常大鼠的基因表达水平进行比较。正常肺组织和肺动脉表达1.7 kb的PDGF-A链转录本和3.5 Kb的PDGF-B链转录本。2.2 kb的c-myc转录本也有表达。低氧暴露7天和14天后，与对照大鼠相比，PDGF-B链和c-myc的mRNA水平显著升高。低氧7天后PDGF-A链mRNA增加，随后下降。这些结果表明，自分泌和/或旁分泌的激活在低氧性肺动脉高压大鼠肺动脉平滑肌细胞的增殖机制中很重要。
