title: Biotransformation of 17-alkyl steroids in the equine: high-performance liquid chromatography-mass spectrometric and gas chromatography-mass spectrometric analysis of fluoxymesterone metabolites in urine samples.
abstract: In this study the equine metabolism of fluoxymesterone (9alpha-fluoro-11beta-17beta-dihydroxy-17alpha-meth ylandrost-4-ene-3-one) given orally has been investigated. The parent material was not detected, but two major 16-hydroxy metabolites which corresponded to a mono- and a di-hydroxylation product were evident. One of the hydroxylation positions was identified as C-16. Phase II metabolism in the form of glucuronide formation was also common. These steroids will provide target compounds for confirming abuse of this drug in the horse.
authors.affiliation: The Jockey Club of Southern Africa, Johannesburg, Gauteng.
authors.forename: S M
authors.initials: SM
authors.lastname: Stanley
authors.forename: S
authors.initials: S
authors.lastname: Kent
authors.forename: J P
authors.initials: JP
authors.lastname: Rodgers
mesh_terms: D045930:Anabolic Agents; D000818:Animals; D001711:Biotransformation; D002851:Chromatography, High Pressure Liquid; D005260:Female; D005474:Fluoxymesterone / Q000493:pharmacokinetics* / Q000652:urine*; D008401:Gas Chromatography-Mass Spectrometry; D005965:Glucuronates / Q000652:urine; D006736:Horses / Q000378:metabolism*; D006900:Hydroxylation; D013058:Mass Spectrometry; D013431:Sulfates / Q000652:urine
chemical_list: D045930:Anabolic Agents; D005965:Glucuronates; D013431:Sulfates; D005474:Fluoxymesterone