Differential Regulation of Endothelial Cell Surface Molecules by Diverse Hemodynamic Forces

Endothelial cells (EC) form the ubiquitous single-cell wide lining of the walls of the entire cardiovascular system. In the arterial tree, EC are exposed to pulsatile blood flow, whereas in the venous and in the lymphatic circulation, blood flow is largely steady laminar. Thus, depending on the anatomical site, EC sense and respond to a variety of flow fields which differ both qualitatively (e.g., steady, reversing or pulsatile, laminar vs. perturbed) as well as quantitatively, e.g., in terms of the force amplitudes. Recent studies suggest that the diverse hemodynamic forces associated with distinct local flow patterns might contribute to the functional basal heterogeneity of EC in vivo and also play a role in vascular pathophysiology (Gimbrone et al., 1997; Nakashima et al., 1998).