The Effect of Creating a Moderate Stenosis on the Localization of Intimal Thickening in the Common Carotid Artery of the Rabbit Fed on a Cholesterol-Rich Diet

Abstract

The effect of a locally disturbed flow on intimal thickening was studied by creating a moderate axisymmetric stenosis (mean diameter reduction: 26%) in common carotid arteries of the rabbit and feeding a cholesterol-rich diet. In eight of nine specimens obtained from four rabbits, intimal thickening occurred at the distal side of the stenosis, mainly in a restricted region which extended from the apex of the stenosis to the distal end, the point of the maximum thickness locating approximately a half of the vessel diameter downstream of the apex of the stenosis. The result was compared with the distributions of wall shear stress and surface concentration of low-density lipoproteins (LDL) which were calculated using a theoretical model of blood flow and LDL transport through the stenosed artery. It was found that the site of intimal thickening well corresponded to the region where wall shear stress was relatively low and surface concentration of LDL was locally elevated. These results suggest that blood flow plays an important role in the localized pathogenesis and development of intimal thickening by locally augmenting concentration polarization of LDL at a blood/endothelium boundary.