Oral contraceptive and Platelet lipid biosynthesis in female rats: dose-response relationship

Female rats were treated with different doses of an oral contraceptive (ethinyl estradiol + lynestrenol) and lipid biosynthesis was studied in blood platelets by acetate incorporation into different fractions separated by thin layer chromatography. A marked increase in lipid biosynthesis was observed, especially in the sterol fractions (cholesterol and lanosterol-dihydrolanosterol). It was dose-dependent, observed after a lag-phase, maximal in 3 days and normalized in 8 days. Thus, the oral contraceptive studied here appears to modify platelet lipid biosynthesis for the entire life of the platelets.