Arterial Lesions in Hypertensive Rats (Shr) on a High Fat Diet

We report an experiment to determine the effects of an atherogenic diet on muscular-type arteries in (heart, mesenterium, pancreas, kidney) hypertensive rats (SHR) for up to 1.5 years. The rats (SHR and nonSHR) were fed a high fat diet with to 10% lard, 1% cholesterol, and 0.5% cholic acid. Some of the SHR showed increased accumulations of foam cells, fibrinoid substances and myointimal cells. Typical atherosclerotic intimal lesions were also found in SH R. There was evidence that both blood mononuclear cells and smooth muscle cells were converted into foam cells in the intima. It is postulated that blood mononuclear cells, fibrinoid substances and myointimal cells play an important role in the formation of intimal foam cell-rich lesions in experimental dietary atherosclerotic lesions. In contrast no atherosclerotic lesions were found in normotensive rats for a period of up to 3 years. Thus hypertension and hypercholesterolemia play important roles in producing foam cell-rich intimal lesions.