Détermination des concentrations physiologiques de la norandrostérone et de la norétiocholanolone, métabolites urinaires de la nandrolone par CPG/SM. Résultats d'une étude multicentrique

Abstract

RESUMELa nandrolone

Effects of High-Intensity Exercises on 13C-Nandrolone Excretion in Trained Athletes

“…[13][14][15][16][17] The use of contaminated supplements often leads to low 19-NA and 19-NE urinary concentrations close to the values measured in this study. Because of significant interindividual variability, no clear conclusions can be drawn about possible consequences of physical effort on nandrolone metabolites excretion in urine.…”

“…Several important issues such as the low concentrations of the nandrolone metabolites in urine, 26,27 the potential endogenous production of these substances, or their exogenous origins are still being debated by the antidoping laboratories. [13][14][15][28][29][30][31][32][33][34][35][36] Initially, our study was aimed at revealing a possible influence of physical effort on the urinary excretion of labeled nandrolone metabolites after exhaustive exercises that resembled a football game. Correctly defining such exercises represented a challenge on its own.…”

“…While the study clearly did not claim to be controlled, 3 hypotheses were proposed to explain the origin of the excreted metabolites: (1) endogenous production, [13][14][15] (2) late release from fatty tissues of previously administered nandrolone or precursor, and (3) intake of a nandrolone-containing product just before the match. It was also suggested that in some specific cases, physical effort could increase the release of 19-NA in urine, regardless of its origin.…”

[13C]Nandrolone Excretion in Trained Athletes: Interindividual Variability in Metabolism

“…The endogenous origin of nandrolone remains a controversial topic, although the existence of small amounts of naturally occurring nandrolone metabolites in urine under physiologic conditions or after physical effort has been demonstrated (12)(13)(14)(15)(16)(17)(18)(19)(20)(21). Nevertheless, in almost all cases, the measured concentrations generally remain far below the threshold limits.…”

La spectrométrie de masse et ses principales applications en biologie médicale

“…• toxiques [40][41][42] : métaux (jusqu'à 34 éléments), cyanures ; • dopage : détection et identification de stéroïdes anabolisants [43], nandrolone et métabolites (norandrostérone et noréthio-cholanolone) ; • stupéfiants et soumission chimique [44] : opiacés [45,46], cocaïniques [47], buprénorphine et norbuprénorphine [48], cannabis [49], LSD [50], dérivés de l'ecstazy [51], GHB [52], kétamine [53]. Remarque : La spectrométrie de masse est, bien sûr, applicable en biologie vété-rinaire ; elle est très présente dans le domaine de l'agroalimentaire et de la protection de l'environnement : • agroalimentaire : dioxine dans les poissons contaminés [54], PCB dans les matières grasses, le lait et les oeufs, [57], explosifs dans les aéroports et les gares [58].…”