Effect of dietary fats and triiodothyronine administration on the lipid components of serum and tissues in the rat.

Twelve groups of rats were included in this study. Six groups (3 males and 3 females) received high fat diets containing 20% of either peanut oil, maize oil or lard. The other six groups received the same diets plus triiodothyronine. Triiodothyronine T3 added to diets containing peanut oil caused slight increase in total serum lipids in female rats, while in male rats serum total lipids were increased about 20-fold. T3 administration caused almost no change in aortic total and all lipid fractions in male rats kept on diets containing any of the fats used. Female rats kept on lard plus T3 showed a rise in cholesterol free and esterified and phospholipid contents of aorta lipids.