Cholesterol levels and eicosanoid production in rats fed phosphatidylinositol or soybean lecithin.

Male young rats were fed 8% corn oil diets supplemented either with 2% phosphatidylinositol (PI) from safflower seeds or soybean lecithin (SL) for 22 days. Other groups of rats were fed 10% corn oil diets with or without (control) 0.3% inositol (IN, equivalent to the inositol moiety of the PI diet). The plasma cholesterol level was low in the SL group whereas liver triglyceride was low in all supplemented groups. The aortic production of prostacyclin tended to be high in rats fed the control diet and low in rats fed the SL diet, the PI and IN groups being intermediate. The concentration of plasma thromboxane B2 was comparable among various groups. In plasma and liver phosphatidylcholine, the ratio of arachidonate/linoleate was low in rats fed SL and high in rats fed PI or IN diets. The results indicate that, in addition to SL, the inositol moiety of PI may have a significant role in the regulation of lipid metabolism.