The aim of this study was to examine the effect of feeding diets containing
heated corn oil (HCO) for a long period (10 hours) on the total cholesterol (TC),
triglycerides (TG) and the total phospholipids (PL) content and the fatty acids pattern in liver, aorta and plasma in a comparison with diets containing fresh corn oil (FCO) in rats. TC and TG content in the liver after one week HCO-feeding increased while PL decreased. TC, TG and PL content decreased in aorta and increased in plasma under the same period of HCO- feeding. After six weeks of HCO-Feeding TC increased acutely in liver and aorta tissues whereas they decreased in plasma. PL decreased in liver and plasma by 21.1 % and 35.9% respectively and increased in aorta by 126.1 % under the same conditions. TG decreased in liver and aorta tissue, while they increased in plasma. The unsaturated, saturated fatty acids (US/S) ratio and essential fatty acids (E.F.A.) specially linoleic acid decreased after one week and decreased more and more after six weeks of HCO-feeding, when they compared by FCO- feeding. So it can be concluded that feeding on long period heated oils led to harmful effect in experimental animals as hypercholesteremia and deficiency of essential fatty acids, which are necessary for many biological processes.