title: The use of nonradiolabelled steroid infusions to investigate the origin of oestrone sulphate in postmenopausal women.
abstract: Infusion of nonradiolabelled dehydroepiandrosterone sulphate (DHA-S) has been used to investigate the possible formation of oestrone sulphate via a sulphated conjugate of androstenedione. The metabolic clearance rate (MCR) of DHA-S also was measured and the mean value (25 1/24h) was similar to values reported using isotopic techniques. Although conversion of DHA-S to 5-androstenediol, a steroid with oestrogenic properties, was detected during infusion of DHA-S, there were no significant increases in plasma levels of conjugated androstenedione or oestrone sulphate. The MCR's oestrone sulphate measured using infusion of nonradiolabelled steroid in two menopausal women were 99 1/24h and 121 1/24h. For one woman, the production rate of oestrone sulphate, calculated from the conversion of oestrone and oestradiol to oestrone sulphate (151 nmol/day) was similar to the measured production rate of oestrone sulphate (144 nmol/day). It is concluded that in menopausal women, oestrone sulphate is derived from conversion of oestrone and oestradiol with no formation occurring via conjugated androstenedione.
mesh_terms: D000734:Androstenediols / Q000097:blood; D000735:Androstenedione / Q000097:blood; D004970:Estrone / Q000031:analogs & derivatives* / Q000097:blood / Q000378:metabolism; D005260:Female; D006801:Humans; D007263:Infusions, Parenteral; D008593:Menopause / Q000378:metabolism*; D008657:Metabolic Clearance Rate; D011714:Pyrans / Q000378:metabolism*; D011753:Pyrones / Q000008:administration & dosage / Q000378:metabolism*
chemical_list: D000734:Androstenediols; D011714:Pyrans; D011753:Pyrones; D004970:Estrone; C027493:dehydroacetic acid; D000735:Androstenedione; C017296:estrone sulfate