Takakuwa O
Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Sapporo, Japan.
Hokkaido Igaku Zasshi. 1990 Mar;65(2):178-88.
Vascular endothelial cells modulate their functions in response to hemodynamic forces such as fluid shear stress. In the present study, we applied shear to cultured bovine aortic endothelial cells (EC) by using a saecially designed apparatus and examined the effects of their homogenate and conditioned medium on such EC and smooth muscle cell (SMC) functions as adhesion, growth, migration or collagen synthesis. Cultured bovine aortic SMC were stimulated to adhere to wells and grow in the presence of EC conditioned medium. This conditioned medium had no effect on EC adhesion and growth. The activities of stimulating SMC adhesion and growth were almost the same in both EC conditioned medium obtained from static cultures and shear-loaded cultures. Studies with filters in a modified Boyden chamber showed that shear-loaded EC homogenate yielded stimulated SMC migration. Also shear-loaded EC cell layer contained increased amount of collagen compared with static EC cell layer. These observations indicate that:(a) EC secrets the substances which stimulate SMC adhesion and growth, but these functions are not affected by shear stress application, (b) EC produces SMC migration stimulators in response to shear stress, and (c) shear stress can enhance EC collagen synthesis. These results are relevant to EC response to hemodynamic forces and its role in the localization of atherosclerotic lesions in vivo.
血管内皮细胞会根据诸如流体剪切应力等血流动力学力来调节其功能。在本研究中，我们使用专门设计的装置对培养的牛主动脉内皮细胞（EC）施加剪切力，并研究其匀浆和条件培养基对EC和平滑肌细胞（SMC）的黏附、生长、迁移或胶原蛋白合成等功能的影响。培养的牛主动脉SMC在EC条件培养基存在的情况下被刺激黏附于孔并生长。这种条件培养基对EC的黏附和生长没有影响。从静态培养和剪切加载培养获得的EC条件培养基中刺激SMC黏附和生长的活性几乎相同。在改良的博伊登小室中使用滤膜进行的研究表明，剪切加载的EC匀浆可促进SMC迁移。与静态EC细胞层相比，剪切加载的EC细胞层中胶原蛋白含量也有所增加。这些观察结果表明：（a）EC分泌刺激SMC黏附和生长的物质，但这些功能不受剪切应力施加的影响；（b）EC会响应剪切应力产生SMC迁移刺激物；（c）剪切应力可增强EC胶原蛋白合成。这些结果与EC对血流动力学力的反应及其在体内动脉粥样硬化病变定位中的作用相关。
