Induction of Rapid Atherogenesis by Perivascular Carotid Collar Placement in Apolipoprotein E–Deficient and Low-Density Lipoprotein Receptor–Deficient Mice

Abstract

Background —Perivascular collar placement has been used as a means for localized atherosclerosis induction in a variety of experimental animal species. In mice, however, atherosclerosis-like lesions have thus far not been obtained by this method. The aim of this study was the development of a mouse model of rapid, site-controlled atherogenesis. Methods and Results —Silastic collars were placed around the carotid arteries of apolipoprotein E–deficient (apoE−/−) and LDL receptor–deficient (LDLr−/−) mice. The development of collar-induced lesions was found to occur predominantly in the area proximal to the collar and to be dependent on a high-cholesterol diet. Lesions were evident in apoE−/− mice after 3 weeks and in LDLr−/− mice after 6 weeks and were overtly atherosclerotic in appearance. Lumen stenosis reached 85% in apoE−/− mice and 61% in LDLr−/− mice 6 weeks after collar insertion. Expression levels of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 were increased both proximal and distal to the collar, whereas endothelial nitric oxide synthase expression was downregulated at the proximal site. Conclusions —We propose that this model of collar-induced acceleration of carotid atherogenesis is of hemodynamic cause. It may serve as a substrate for sequential mechanistic studies concerned with the underlying cause and pathogenesis of atherosclerosis. The rapidity of lesion development will also aid the efficient screening of new potentially antiatherogenic chemical entities and the evaluation of therapies with limited duration of effectiveness, such as adenoviral gene therapy.