STUDY ON MICRO-BIOMECHANICS OF PERMEABILITY OF ENDOTHELIAL CELLS

点击翻译按钮获取中文摘要

Macromolecular transport across the endothelial cells play an important role for the development of atherosclerotic lesionbecaouse of its principal barrier to transport to arterial vessel wall. The transport routes of macromolecule includes pinocytotic vesicles and intercellular junctions and its shear dependent property remains unknown. The advantage of confocal laser scanning microscopy is to observe the macromolecule transport in the cell in situ. we made both qualitative microscopic observation and quantitative evaluation based on the macroscopic measurements of permeability. To reveal the feature of macromolecular transport through the cultured endothelial cells, the microscopic feature of transport was observed by confocal laser scanning microscopy and the macroscopic permeability was measured by diffusion chamber with flow system.Pig aortic endothelial cells were harvested and cultured in incubator. Cells used in experiments were in the fifth to seventh passage. Microscopic views of transport of FITC-Dextran 70 and FITC-albumin were observed by the confocal laser scanning microscopy (MRC-600, Bio Rad Co. Ltd.). The cells on cover slips were incubated in the Krebs Ringer Glucose solution containing FITC-Dextran 70 for 15 minutes, and were rinsed by KRG solution for three times. Then they were observed by the phase contrast and confocal laser scanning microscopy. Macroscopic feature of transport of FITC-Dextran across the cell layr was measured by the diffusion chamberNumerous bright spots appeared inside the cells, but did not remarkably appear at the intracellular junctions. Furthermore the vertical scanning gave the channel-like structure formed by the vesicles. The dependency of uptake on the shear stress in peculiar and the uptake at the low shear stress increases, on the other land the uptake at the high shear stress decreases. This striking result gives an important significance to the mechanism of atheloscrelotic formation.