Maximum wall shear at the nuclear bulge of endothelial cells and their alignment along the blood flow - a computational fluid mechanical study

The mechanism of arterial endothelial cell deformation and alignment was studied using a three dimensional computational fluid mechanical model of the arteriolar wall with regularly arranged intraluminal undulation simulating the endothelial cells. Endothelial cells were simulated using a 2D Gaussian distribution function, which had three parameters used to define the shape of the cells. They were the elongation factor, which is the correlation coefficient of the Gaussian distribution function, the height of the cells, and the cellular angle against the blood flow. The Navier Stokes equations of the Newtonian fluid with steady flow conditions were solved using a finite volume method and the absolute wall shear stress(WSS) at the summit of the cells was calculated. The WSS at the nuclear bulge varied in a complex manner and the hypothesis that the endothelial cells change their shape and alignment to minimize the WSS at the nuclear bulge was shown to explain the computed results.