An Evaluation of the Relationship of Dietary Fatty Acids to Incidence of Myocardial Lesions in Male Rats

Abstract

Published results of 23 experiments involving cardiopathological examinations of young growing male albino rats at 4 independent laboratories were pooled. All the weanling rats had been fed test fats or vegetable oils at 20% by weight in the diet for 16 or 24 weeks. Data from rapeseed oils with more than 7.4% erucic acid (22:1) were not used. Regression analyses of the aggregate data, corrected for differences among experimental means, were carried out with observed incidence of myocardial lesions as the dependent variable and fatty acid compositions (% by weight) of the fats and oils as independent variables.Differences in the observed incidence of lesions for the various diets were negatively correlated with their levels of palmitic (16:0) and stearic (18:0) acids and positively correlated with levels of linolenic acid (18:3). Smaller correlations were found between myocardial lesion incidence and the content of 22:1 and other fatty acids present in the fats and oils.The results of the analyses suggest that the incidence of myocardial lesions in young growing male albino rats fed high fat (20% by weight) diets for 16 to 24 weeks is related to the levels of fatty acids in their diets.