Relationship between energy-dependent macromolecule uptake and transport granules in the endothelial cells affected by wall shear stress

The purpose of this study is to reveal (1) the effect of shear stress on the albumin uptake area and its content per unit area, and (2) the energy dependence of albumin uptake into endothelial cells. The uptake of the fluorescent labeled albumin was visualized with a confocal laser scanning microscope. The uptake into the endothelial cells is inhibited completely at 4°C or by 1 μM p-trifluoromethoxy-phenylhydrozone (FCCP), which is a potent energy metabolism inhibitor. This result indicates that albumin uptake is an energy-dependent, active transport. At 10 dyn/cm², at 5 μm the uptake area increases by 363% and the albumin content per unit area increases by 192%. At 60 dyn/cm², at 3 μm the area decreases by 21% and the albumin content decreases by 54%. It is, therefore, considered that the effect of shear stress on the uptake area is more dominant than on the albumin content per unit area.