Köster R, Windstetter U, Uberfuhr P, Baumann G, Nikol S, Höfling B
Department of Internal Medicine, University of Munich, Germany.
Angiology. 1995 Feb;46(2):99-106. doi: 10.1177/000331979504600202.
Proliferation and migration of vascular smooth muscle cells (SMCs) are major events in atherogenesis. It is known that platelet-derived growth factor (PDGF) stimulates both of these processes in a paracrine fashion, whereas autocrine stimulation has been shown only for proliferation. The aim of this study was to investigate the influence of PDGF expression in SMCs on migratory activity of these cells. SMCs were cultivated from the vascular tissue of 23 patients. Cellular motility was analyzed by a computer-assisted motion analysis system; 54 images per sample, obtained during an observation period of eighteen hours, were analyzed. PDGF-A and PDGF-B mRNA levels were determined by quantitative polymerase chain reaction (PCR) following reverse transcription. To quantitate mRNA content of SMCs, the authors coamplified cDNA copies of mRNA from cells and from a synthetic reference RNA in the same reaction vessel. Cells derived from atherosclerotic lesions produced a 1.6-fold increase of PDGF-A (P < 0.05) and a 5-fold increase of PDGF-B mRNA (P < 0.05) as compared with those from normal vessels. The migratory velocity (range 11.1-49.2 microns/hr) was independent of PDGF-A and PDGF-B mRNA expression. A significant correlation between levels of PDGF-A mRNA and PDGF-B mRNA and the degree of directional changes of SMCs on the covered track (klinokinesis) was found (P < 0.05).
PDGF-A and PDGF-B mRNA expression is significantly correlated with positive klinokinesis without affecting migratory velocity. This finding reflects enhanced migratory activity of SMCs. Besides its known mitogenic effects, the authors present evidence that PDGF may act as an autocrine motogen* in SMCs.
血管平滑肌细胞（SMC）的增殖和迁移是动脉粥样硬化形成过程中的主要事件。已知血小板衍生生长因子（PDGF）以旁分泌方式刺激这两个过程，而自分泌刺激仅在增殖方面得到证实。本研究的目的是探讨SMC中PDGF表达对这些细胞迁移活性的影响。从23例患者的血管组织中培养SMC。通过计算机辅助运动分析系统分析细胞运动性；在18小时的观察期内，每个样本获取54张图像并进行分析。逆转录后通过定量聚合酶链反应（PCR）测定PDGF-A和PDGF-B mRNA水平。为了定量SMC的mRNA含量，作者在同一反应管中共同扩增细胞mRNA和合成参考RNA的cDNA拷贝。与正常血管来源的细胞相比，动脉粥样硬化病变来源的细胞产生的PDGF-A增加了1.6倍（P<0.05），PDGF-B mRNA增加了5倍（P<0.05）。迁移速度（范围为11.1-49.2微米/小时）与PDGF-A和PDGF-B mRNA表达无关。发现PDGF-A mRNA和PDGF-B mRNA水平与SMC在覆盖轨迹上的定向变化程度（klinokinesis）之间存在显著相关性（P<0.05）。
PDGF-A和PDGF-B mRNA表达与正向klinokinesis显著相关，而不影响迁移速度。这一发现反映了SMC迁移活性增强。除了其已知的促有丝分裂作用外，作者还提供证据表明PDGF可能作为SMC中的自分泌运动原*。
