[Metabolism of lipoproteins in rats treated with ethinyl estradiol].

Effect of ethinyl-estradiol on metabolism of lipoproteins was studied in rat blood. Administration of ethinyl-estradiol at a dose of 50 micrograms/kg of body mass led to hypocholesterolemia and to hypertriglyceridemia in blood of experimental animals as well as the hormone impaired lipid composition of all the lipoprotein classes. These alterations in lipid composition of lipoproteins occurred as a result of an increase in biosynthesis and secretion of very low density lipoproteins as well as due to impairments of lipoprotein transformation in blood serum caused by a decrease in activity of main enzymes responsible for the transformation of lipoproteins in circulation--lipoprotein lipase, liver triglyceride lipase and lecithin-cholesterol acyltransferase.