title: In vitro formation of testosterone via the delta 5-pathway in the human umbilical cord.
abstract: Homogenates of two groups of term umbilical cord (n = 6, 37-40 weeks; n = 6, 38-40 weeks) were separately incubated with [7n-3H]pregnenolone and [1,2,6,7-3H]dehydroepiandrosterone. Using the reverse-isotope dilution technique, [3H]dehydroepiandrosterone and [3H]testosterone formed from the respective substrates were isolated and characterized. The extent of enzymic conversions were 0.015-0.28% and 0.044-2.2%. These results provide evidence for the metabolic transformation of pregnenolone to testosterone via the delta 5-3 beta-hydroxy route.
authors.affiliation: University Department of Obstetrics and Gynaecology, National University Hospital, Singapore.
authors.forename: A
authors.initials: A
authors.lastname: Loganath
authors.forename: R
authors.initials: R
authors.lastname: Gunasegaram
authors.forename: K L
authors.initials: KL
authors.lastname: Peh
authors.forename: W P
authors.initials: WP
authors.lastname: Chow
authors.forename: P C
authors.initials: PC
authors.lastname: Chew
authors.forename: S
authors.initials: S
authors.lastname: Shanmugaratnam
mesh_terms: D002845:Chromatography; D002855:Chromatography, Thin Layer; D003687:Dehydroepiandrosterone / Q000378:metabolism; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D010084:Oxidation-Reduction; D011284:Pregnenolone / Q000378:metabolism*; D013739:Testosterone / Q000096:biosynthesis*; D014470:Umbilical Cord / Q000378:metabolism*
chemical_list: D013739:Testosterone; D003687:Dehydroepiandrosterone; D011284:Pregnenolone