title: Estradiol is a potent inhibitor of the hypotriglyceridemic effect of levonorgestrel in female rats.
abstract: The progestin, levonorgestrel, when administered to rats intramuscularly, significantly lowered both total and very low density lipoprotein triglyceride concentrations in the blood plasma by 35-40%. This effect was readily abolished by the simultaneous intramuscular administration of estradiol benzoate. Similarly, estradiol-17 beta overcame the inhibitory effects of levonorgestrel on the incorporation of [9,10-3H]palmitate into triglycerides of freshly isolated rat hepatocytes studied in vitro. However, estradiol alone significantly raised plasma triglycerides by two-fold in vivo. Estradiol also significantly enhanced (by 9%) the incorporation of [9,10-3H]palmitate into hepatocyte triglycerides. These results suggest that the effects of estradiol on triglyceride synthesis and concentration dominate over those of levonorgestrel in the rat.
authors.affiliation: Department of Biochemistry, University of Western Ontario, London, Canada.
authors.forename: E H
authors.initials: EH
authors.lastname: Taves
authors.forename: B M
authors.initials: BM
authors.lastname: Wolfe
mesh_terms: D000818:Animals; D002784:Cholesterol / Q000097:blood; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D016912:Levonorgestrel; D009644:Norgestrel / Q000037:antagonists & inhibitors*; D051381:Rats; D014280:Triglycerides / Q000097:blood*
chemical_list: D014280:Triglycerides; D009644:Norgestrel; D004958:Estradiol; D016912:Levonorgestrel; D002784:Cholesterol