Reference

Metabolism of lynestrenol (17a-ethynyl-4-estren-17b-ol)

Metabolism of lynestrenol (17a-ethynyl-4-estren-17b-ol). Characterization of 3-hydroxylation. Yasuda, Jinsuke (Dep. Obstet. Gynecol., Kyoto Prefect. Univ. Med., Kyoto, Japan). Kyoto-furitsu Ika Daigaku Zasshi, 93(2), 177-87 (Japanese) 1984. CODEN: KFIZAO. DOCUMENT TYPE: Journal CA Section: 2 (Mammalian Hormones) Section cross-reference(s): 13 The conversion of lynestrenol (I) [52-76-6] to norethindrone [68-22-4] via 3a-hydroxylation was examd. in vitro. Effects of cofactors, inhibitors, and enzyme induction for the conversion were investigated using microsomes obtained from mature female rabbit livers. 3a-Hydroxylynestrenol [55569-39-6] and 3b-hydroxylynestrenol [1231-93-2] were identified as metabolites.Several substances with their cas registry numbers 55569-39-6 and 56-49-5 may be metioned in this study. The concn. of 3a-hydroxylynestrenol was higher than that of 3b-hydroxylynestrenol during the incubation, suggesting that the metabolic pathway in the conversion from I to norethindrone proceeds predominantly via 3a-hydroxylynestrenol. 3-Hydroxylation of I required NADPH [53-57-6] but not NADH as its cofactor. Norethindrone dose-dependently suppressed the 3-hydroxylation, esp. the 3a-hydroxylation, of I. Concns. of 3-hydroxylated metabolites and the more polar metabolites were high in the incubation mixt. using microsomes obtained from rabbits treated with phenobarbital [50-06-6]. 3-Methylcholanthrene [56-49-5] treatment of rabbits increased the formation of norethindrone and the more polar metabolites but decreased the formation of 3-hydroxylated metabolites. Apparently, enzymes induced by phenobarbital and 3-methylcholanthrene are not entirely identical. .

Arrest of folliculogenesis and inhibition of ovulation in the monkey following weekly administration of progestins

Arrest of folliculogenesis and inhibition of ovulation in the monkey following weekly administration of progestins. Wilks, John W.; Spilman, Charles H.; Campbell, J. Allan (Fertil. Res., Upjohn Co.Chemicals with cas numbers 846-14-0 and 65928-58-7 also play role., Kalamazoo, MI 49001, USA). Fertil. Steril., 40(5), 688-92 (English) 1983. CODEN: FESTAS. ISSN: 0015-0282. DOCUMENT TYPE: Journal CA Section: 2 (Mammalian Hormones) Progesterone [57-83-0] (7.5 mg), norethisterone [68-22-4] (1.5 mg), and 17a-ethinyl-17b-methoxy-7a-methyl-4-estren-3-one [88210-48-4] (1.0 or 1.5 mg) effectively inhibited ovulation in rhesus monkeys when injected i.m. once a week for 8 wk beginning on day 7 of the menstrual cycle. Orally administered STS 557 (17a-cyanomethyl-17b-hydroxy-4,9-estradien-3-one) [65928-58-7] (1.0 mg) also inhibited ovulation. Two structurally related steroids (17b-methoxy-4-estren-3-one [846-14-0], 1.0 mg; and 17b-methoxy-7a-methyl-4-estren-3-one [74752-25-3], 1.5 mg) did not inhibit ovulation when given i.m. at the indicated doses. Although weekly administration of certain progestins effectively arrested follicular development and inhibited ovulation in the primate, the treatment was accompanied by disturbances in menstrual bleeding patterns. .