Age-related differences in the distribution and occurrence of atherosclerotic aortic lesions in the hyperlipemic rabbit

Aging is to be considered a relevant risk factor in the pathogenesis of atherosclerosis. It is argued whether the aging/atherosclerosis relationship should be considered the result of an increased susceptibility of the vessel exposure to risk factors. Aged and young white New Zealand rabbits received a hyperlipemic diet enriched with a low dose of cholesterol for 18 months. In aged hyperlipemic rabbit aortas, the presence and prevalence of fibroatheromatous plaques similar to the lesions observed in human atherosclerosis were observed, whereas in young hyperlipemic rabbits only fatty streaks were present, with no differences in plasma cholesterol levels between the two groups. Moreover, in the aged hyperlipemic rabbits, the lesions were of greater size and more diffuse than in young animals, and often present in the abdominal tract of vessels.