Comparison of rats with mice concerning the response of lipid metabolism to dietary fats.

Rats and mice were compared regarding their responses to cholesterol-free or high-cholesterol diets containing either corn oil or coconut fat. In rats fed a cholesterol-free diet, but not in the mice, corn oil caused an increase in serum and liver cholesterol when compared with coconut fat. Corn oil reduced serum triglycerides and increased fecal excretion of neutral steroids in the rats, whereas these variables were not affected in the mice. Fecal bile acid excretion was reduced in mice but not altered in rats. When the diets contained 1% (w/w) of cholesterol, the rats and mice responded rather similar to corn oil. This study suggests that the response to dietary fats can be species-dependent in some respects.