title: Human nutritional supplements in the horse. Dehydroepiandrosterone versus androstenedione: comparative effects on the androgen profile and consequences for doping analysis.
abstract: Dehydroepiandrosterone (DHEA) and androstenedione are weak androgens, which need conversion to more potent testosterone in order to enhance anabolic action. Consequences of oral dosing at 1 mg/kg on the urinary and plasma androgen profile of mare and gelding have been evaluated with an analytical method involving conjugate fractionation and selective hydrolysis, group separation, and quantitation by gas chromatography-mass spectrometry with selected ion monitoring of trimethylsilyl ethers. Peak levels of testosterone total conjugates in urine (range 300-6000 microg/L) were attained a few hours after dosing. Renal clearance was fast, so the testosterone detection period lasted only 20 to 33 h, the longest time being generated by androstenedione. The urinary testosterone/epitestosterone ratio for detection of exogenous testosterone in the mare was inoperative after DHEA administration because there was a concomitant increase of epitestosterone, which thereby acted as a masking agent. Androstanediols and androstenediols, as well as some 17-ketosteroids, were additional markers. A transient increase of circulating free testosterone has been evidenced, and this would support possible anabolic/androgenic action by supplementation with DHEA and androstenedione along the oral route.
authors.affiliation: Laboratoire de la Fédération Nationale des Courses Françaises, Châtenay-Malabry, France. ldehennin@aol.com
authors.forename: L
authors.initials: L
authors.lastname: Dehennin
authors.forename: Y
authors.initials: Y
authors.lastname: Bonnaire
authors.forename: P
authors.initials: P
authors.lastname: Plou
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics / Q000652:urine; D000284:Administration, Oral; D000735:Androstenedione / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics / Q000652:urine; D000818:Animals; D015415:Biomarkers / Q000032:analysis; D003687:Dehydroepiandrosterone / Q000008:administration & dosage / Q000032:analysis / Q000097:blood* / Q000493:pharmacokinetics / Q000652:urine; D004300:Doping in Sports; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006736:Horses / Q000502:physiology*; D008297:Male; D016482:Urinalysis / Q000662:veterinary
chemical_list: D000276:Adjuvants, Immunologic; D015415:Biomarkers; D000735:Androstenedione; D003687:Dehydroepiandrosterone