Suppression of Experimental Atherosclerosis in Dogs by Dietary Linoleic Acid. ∗

Abstract

Summary

Severe atherosclerotic lesions were induced in 4 months in dogs fed a diet restricted in linoleic acid content and supplemented with cholesterol and thiouracil. Only one minor lesion was found in a group of dogs fed a similar diet supplemented with cholesterol and thiouracil which was isocaloric in fat but contained a high concentration of linoleic acid. In the low linoleic acid group, serum total cholesterol increased to high levels within 2 months and remained constant for the remainder of the feeding period. In the high linoleic acid group, serum total cholesterol levels increased more slowly reaching levels compatible with the group fed low linoleic acid diets at the end of 4 months. Less than 25% of the serum esterified cholesterol was bound to linoleic and arachidonic acids in dogs fed diets low in linoleic acid, whereas this value was 75% in dogs fed high linoleic acid diets. It is concluded that dietary linoleic acid retards lesions in dogs by promoting cholesterol excretion.