Lipid metabolic studies in oophorectomized women: effects of synthetic progestogens on individual serum phospholipids and serum lecithin fatty acid composition.

Abstract

Norethisterone acetate (NET), levonorgestrel (NORG) and medroxyprogesterone acetate (MPA) were administered to oophorectomized women to evaluate the effects on individual serum phospholipids as well as serum lecithin and cholesterol ester fatty acid composition. Blood samples were drawn after a 3-week period without hormonal replacement therapy and after 3 weeks on each progestogen. NORG reduced cepahlin and lecithin with a concomitant increase in lysolecithin. This shift in individual phospholipids has previously been induced by exogenous androgens. The 17C-alkylated synthetic progestogens NET and NORG but not the non-alkylated MPA caused a redistribution among the 1-position fatty acids of serum lecithin with an increase in palmitic concomitant with a decrease in stearic acid. These findings indicate differences between 19-nortestosterone derivatives and 17-hydroxyprogesterone derivatives in effect on individual serum phospholipids and in influence on liver lecithin synthesis as judged from serum lecithin fatty acid composition.