Background

Atherosclerosis is a frequent contributing factor underlying acute myocardial infarctions (MI) and cerebral vascular accidents, the two most common forms of cardiovascular disease. Approximately 1.1 million Americans suffer myocardial infarctions annually, and approximately half this number will suffer from a cerebral vascular accident (stroke).   Atherosclerosis, is a disease of medium and large arteries that coats the interior surface of these vessels with plaque.  When this plaque is damaged in some way exposing the vessel walls, it is believed that clot formation is initiated and this then causes acute myocardial infarction (MI) if it occurs in the coronary arteries, or a cerebral vascular accident, if it occurs in the brain.  The appearance of atherosclerosis is correlated with elevated serum cholesterol, but a number of additional factors such as elevated HDL have been implicated.

Models

Animal models of atherosclerosis mimic to a certain degree what is known about the process in humans.  They involve feeding mice, hamsters or guinea pigs a high cholesterol diet, to induce plaque formation, followed by mechanical injury to the plaque to stimulate clot formation.  Both hamsters and guinea pigs develop atherosclerosis in response to a high fat diet in ways that have useful similarities to humans.  The use of mice is primarily for the wide variety of transgenic models available, primarily targeting genes that affect lipoprotein metabolism or activity.