Build-up of visible atherosclerotic plaque in the arteries is readily quantifiable. The mouse and the rabbit provide useful models for understanding the pathogenesis of atherosclerosis by investigating the effects of genetic and dietary perturbations.

Although the wild type mouse does not develop atherosclerosis, atherosclerosis susceptibility genes have been identified in some laboratory mouse strains which do. Furthermore, transgenic technology and gene targeting have produced genetically modified mice that express various apolipoproteins, enzymes and cofactors involved in human lipoprotein metabolism. Gene “knockout” technology allows transgene expression without interference from homologous genes. One notable “knockout” mouse, deficient in apolipoprotein E, develops spontaneous atherosclerosis on a normal chow diet. Transgenic modulations of the atherosclerotic responses of these highly susceptible mice are more pronounced and easily measured. Small, cheap and fast breeding, mice are convenient animal models. But to make mice susceptible to atherosclerosis, their genetic background has to be so drastically altered that the resulting lipoprotein metabolism may not model the human metabolism accurately enough.