In vitro formation of testosterone via the delta 5-pathway in the human umbilical cord.
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.
Loganath
A
A
University Department of Obstetrics and Gynaecology, National University Hospital, Singapore.
Gunasegaram
R
R
Peh
K L
KL
Chow
W P
WP
Chew
P C
PC
Shanmugaratnam
S
S
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*
D013739:Testosterone; D003687:Dehydroepiandrosterone; D011284:Pregnenolone