Abstract
Using our perfusion system that enables the independent control of pressure and flow volume, we investigated the effect of exposure to physiological pulsatile flow on adhesion molecule expression in activated endothelial cells by immunofluorescence. Cultured human umbilical vein endothelial cells (HUVECs) were incubated with 25 ng/ml TNF-α (Tumor Necrosis Factor-alpha) for 6 hours. Then, activated endothelial cells were exposed to physiological pulsatile flow (pressure 80/120 mmHg and shear stress 1.2/1.8 Pa) or physiological steady flow without pressure (shear stress 1.5 Pa) for 1-24 hours. After exposure to pulsatile flow endothelial cells were fixed and stained ICAM-1 (intercellular adhesion molecule-1). Results showed that the expression of TNF-α-induced ICAM-1 decreased time-dependently in HUVECs exposed to physiological pulsatile flow. However, physiological steady flow without pressure increased the expression of TNF-α-induced ICAM-1. These results suggest that physiological pressure and pulsation regulated the expression of adhesion molecule, which induced by endothelial dysfunction.
