Biomaterial Database

Metabolism of D- and L-norgestrel in humans. 1975

R J Warren, and K Fotherby

Levels of DL-norgestrel, D-norgestrel, L-norgestrel and norethisterone were measured in blood by radioimmunoassay after oral administration of the progestin to 3 healthy male subjects and the half-lives calculated. Half-lives for D-norgestrel were much lower than those of L-norgestrel and similar to those of norethisterone. Measurement of norgestrel in blood can therefore be misleading unless the biologically active D-isomer is estimated. Since there was no difference in half-lives between norgestrel and norethisterone the greater potency of the former is probably due to it more strongly binding to target organ receptors.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009640	Norethindrone	A synthetic progestational hormone with actions similar to those of PROGESTERONE but functioning as a more potent inhibitor of ovulation. It has weak estrogenic and androgenic properties. The hormone has been used in treating amenorrhea, functional uterine bleeding, endometriosis, and for CONTRACEPTION.	19-Norpregn-4-en-20-yn-3-one, 17-hydroxy-, (17alpha)-,Ethinylnortestosterone,Norethisterone,Norpregneninolone,Conceplan,Micronor,Monogest,Nor-QD,Norcolut,Norcolute,Norethindrone, (1 beta)-Isomer,Norlutin,Nor QD,NorQD
D009644	Norgestrel	A synthetic progestational agent with actions similar to those of PROGESTERONE. This racemic or (+-)-form has about half the potency of the levo form (LEVONORGESTREL). Norgestrel is used as a contraceptive, ovulation inhibitor, and for the control of menstrual disorders and endometriosis.	18,19-Dinorpregn-4-en-20-yn-3-one, 13-ethyl-17-hydroxy-, (17alpha)-(+-)-,DL-Norgestrel,Neogest,Ovrette,Postinor,Wy-3707,DL Norgestrel,Wy 3707,Wy3707
D011956	Receptors, Cell Surface	Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.	Cell Surface Receptor,Cell Surface Receptors,Hormone Receptors, Cell Surface,Receptors, Endogenous Substances,Cell Surface Hormone Receptors,Endogenous Substances Receptors,Receptor, Cell Surface,Surface Receptor, Cell
D006207	Half-Life	The time it takes for a substance (drug, radioactive nuclide, or other) to lose half of its pharmacologic, physiologic, or radiologic activity.	Halflife,Half Life,Half-Lifes,Halflifes
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D013237	Stereoisomerism	The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)	Molecular Stereochemistry,Stereoisomers,Stereochemistry, Molecular,Stereoisomer