Objective The effect of vascular smooth muscle cells (VSMCs) on the PDFG\|B mRNA expression of Co\|cultured endothelial cells (ECs) under shear stress had been studied in order to provide some experimental data for preventing the development of restenosis resulted from VSMCs proliferation in the vascular graft. Methods The level of PDGF\|B mRNA of ECs cultured alone and Co\|cultured with VSMCs exposed to shear stress were investigated by the methods of in situ hybridization and image analysis. Both controls of ECs cultured alone and Co\|cultured with VSMCs were maintained under static conditions. Results In static condition, the content of PDGF\|B mRNA expression of Co\|cultured ECs was lowered in comparison with ECs alone\|cultured. Under shear stress, PDGF\|B mRNA expression of Co\|cultured ECs was increased in transient manner at 1hour after the onset of shear stress and then returned to the level lower than the static level of Co\|cultured ECs at 6hours after being exposed to shear stress. The transient increasing time of PDGF\|B mRNA expression of Co\|cultured ECs reached a maximum earlier than that of ECs cultured alone.Conclusion Under shear stress, PDGF\|B mRNA expression of ECs Co\|cultured with VSMCs is lowered, which may be favor of inhibiting VSMCs proliferation.

The construction and amount of fibronectin (Fn), laminin (Ln) and collagen type IV (ColIV) in the extracellular matrix of endothelial cells (EC) co-cultured with vascular smooth muscle cells (VSMC) under shear stress were studied by immuno-fluoro-cytochemistry, laser confocal scanning microscopy and image analysis methods to detect the effect of shear stress on adhesion of EC for vascular tissue engineering. One group of EC was maintained under static conditions as a control. In the control, both Fn and Ln exhibited as a granular pattern in perinuclear area and a fibrillar pattern localized underneath EC, and Col IV exhibited mainly as the granular in the perinuclear area, but the fibrillar was fewer. On exposure of EC to shear stress in physiological range, Fn grouped into fibril tracts, and there was a tendency for some of these tracts of fibrils to align with direction of shear stress. Ln and Col IV also grouped into fibril tracts, which, in contrast to Fn, were randomly oriented, Simultaneously, all contents of the extracellular matrix had different quantitative alterations. These results suggest that the capability of adhesion of EC co-cultured with VSMC may be strengthened under shear stress.
Animals ; Animals, Newborn ; Cattle ; Cell Adhesion ; Cells, Cultured ; Collagen Type IV ; metabolism ; Endothelium, Vascular ; cytology ; metabolism ; Extracellular Matrix ; metabolism ; Extracellular Matrix Proteins ; metabolism ; Fibronectins ; metabolism ; Laminin ; metabolism ; Muscle, Smooth, Vascular ; cytology ; metabolism ; Stress, Mechanical