EFFECTS OF A HIGH FAT-HIGH ERUCIC-ACID DIET ON THE LIPID-METABOLISM AND CONTRACTILITY OF THE RAT-HEART

When male weaning rats were fed a high fat-high erucic acid (mustard seed oil) diet for 1 week, there were (i) an increase in the triglyceride and erucic acid contents in the myocardium, and (ii) an increase in the rate of incorporation of [1-14C]palmitic and [14-14C]erucic acids into triglyceride in the perfused heart, in comparison to rats which had consumed a high fat-high linoleic acid (corn oil) diet or a low fat diet (laboratory chow). However, continuation of the mustard seed oil diet (3-6 weeks) resulted in near normalization of these biochemical parameters. Neither of the high fat diets influenced the maximal developed force (per unit cross-sectional area) of the isolated papillary muscle, although the size of the muscle isolated from the mustard seed oil-fed rats was greater. Therefore, a disturbance in cardiac lipid metabolism, as a result of the feeding of a high fat-high erucic acid diet, did not influence the contractility of the isolated papillary muscle. © 1979.