Does chylomicronemia cause atherosclerosis?

Does chylomicronemia cause atherosclerosis? To directly address this clinically important problem, we conducted experiments in guinea pigs which lack apolipoprotein CII and develop chylomicronemia when they are fed a high-fat diet. After 6-12 months on a high-fat diet, guinea pigs were sacrificed, and subjected to histopathological and ultrastructural examination. Both the aorta and the coronary arteries revealed no atherosclerotic changes in all 4 animals examined: the endothelium was intact, and neither lipid-laden foam cells nor migrating cells were present within the arterial wall. Our studies indicate that chylomicronemia does not predispose to atherosclerosis.