Urinary excretion of 19-norandrosterone of endogenous origin in man: quantitative analysis by gas chromatography–mass spectrometry

Dehennin, L.; Bonnaire, Yves; Plou, P.

doi:10.1016/s0378-4347(98)00480-0

Cited by 71 publications

(50 citation statements)

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“…The 12 C in positions 3 and 4 of the molecule was substituted by 13 C. By this substitution we could clearly differentiate analytically between eventual endogenous and administered nandrolone, particularly at the end of the urine collections, when the excretion rates were lower. Nandrolone metabolism is not affected by these chemical changes, and creatinine and specific gravity…”

Section: Resultsmentioning

confidence: 99%

“…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.…”

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confidence: 99%

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

Baume¹,

Avois²,

Schweizer³

et al. 2004

Clinical Chemistry

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Background: Nandrolone is one of the most abused anabolic steroids, and its use in doping is increasing, as revealed by numerous positive cases during recent years in various sports. Different authors have reported the possible natural production of nandrolone metabolites in humans, and some of these authors argued that exhaustive exercise could increase nandrolone production in the body or induce dehydration and consequently lead to an increase of nandrolone metabolites in urine. Methods: Volunteers (n ‫؍‬ 22) ingested two 25-mg doses of [13 C]nandrolone at 24-h intervals and collected urine specimens for 5 days. The labeled nandrolone metabolites 19-norandrosterone and 19-noretiocholanolone were identified and quantified by gas chromatographymass spectrometry. Results: Interindividual variability was observed in nandrolone excretion patterns and kinetics, as well as for the noretiocholanolone:norandrosterone ratio. The amounts of nandrolone metabolites measured at the excretion peak varied between 1180 and 38 661 g/L for norandrosterone and 576 and 12 328 g/L for noretiocholanolone. At the end of the excretion period, the noretiocholanolone:norandrosterone ratio was sometimes >1. The analysis of numerous spot-urine samples allowed the determination of an acceptable correlation between urinary creatinine and specific gravity for placebo-and steroid-treated individuals: y ‫؍‬ 0.0052ln(x) ؉

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Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 99%

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

Baume¹,

Avois²,

Schweizer³

et al. 2004

Clinical Chemistry

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“…Concernant cette possible ingestion de viande contaminée, selon les statistiques des laboratoires de référence de l'Union Européenne, les taux de résidus de nandrolone dans la viande des animaux traités n'excèdent pas 100 ng/Kg. On peut donc en déduire que la quantité de viande qui devrait être consommé pour atteindre les valeurs de l'ordre de 2 ng/mL serait de l'ordre du Kg (18,24).…”

Section: Instrumentationunclassified

“…Il faut également signaler que des gélules de 4 et 5-androsténediol commercialisés au USA induisent une faible excrétion de NA et de NE dans des rapports souvent inversés et à des concentrations proches de celles observées chez des sportifs contrôlés positivement (22). Dehennin et coll avaient aussi montré que la 19 norandrostenedione produisaient les mêmes metabolites que la nandrolone (18). Ceci n'est pas surprenant puisque l'on sait qu'il existe un équilibre entre testosterone et androstenedione, cet équilibre doit se retrouver sur les formes 19 déméthylées (figure 5).…”

Section: Instrumentationunclassified

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

et al. 2000

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“…Traditionally, NT residue analysis has relied upon classical analytical methods, such as gas chromatography coupled to mass spectrometric (GC-MS) [6,[12][13][14], liquid chromatography coupled to mass spectrometric (LC-MS) [15][16][17], and other quantitative methods. Chromatographic techniques generally require highly skilled personnel, laborious sample pretreatment and high-cost, complex equipment.…”

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confidence: 99%

Preparation of monoclonal antibody based indirect competitive ELISA for detecting 19-nortestosterone residue

et al. 2011

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has been illegally used in horse racing to boost physical performance, and in animal husbandry to accelerate weight gain. To monitor the abuse of NT, our goal was to develop a commercial enzyme linked immunosorbent assay (ELISA) kit. For this purpose, hybridomas were prepared by fusing NS0 mouse myeloma cells with splenocytes isolated from immunized BALB/c mouse. Noncompetitive and competitive indirect ELISA were used to screen positive cell clones. To optimize the indirect competitive ELISA (icELISA) method, various methanol concentrations in assay buffer were evaluated. Matrix effects in urine and spiking test were also investigated. Finally, five hybridoma cell lines named NT-1, NT-2, NT-3, NT-4 and NT-5 were screened out. The corresponding monoclonal antibodies (mAbs) were of the IgG 1 isotype with a k light chain, and the antibody affinity of all mAbs were between 2.6×10 9 and 4.7×10 9 L/mol. The titer and IC 50 values of purified ascites were in the range of 0.64×10 5 −2.56×10 5 and 0.55-1.0 ng/mL, respectively. Based on the NT-1 hybridoma, a heterologous icELISA method was developed for the quantitative detection of NT in cattle urine. The dynamic range was from 0.004 to 85.8 ng/mL, with a detection limit for the assay and IC 50 values of 0.002 and 0.55 ng/mL, respectively. Except for a high cross-reactivity (62%) to α-NT, negligible cross-reactivity to other compounds was observed. After optimization, 10% of methanol was used in the assay buffer, and a 20-fold dilution in cattle urine gave an inhibition curve almost the same as that in phosphate buffered saline. The correlation coefficient between the established icELISA and LC-MS/MS method was 0.9871. The results showed that the established heterologous icELISA method provides an excellent alternative for the detection of NT residues in food producing animals. 19-nortestosterone

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Urinary excretion of 19-norandrosterone of endogenous origin in man: quantitative analysis by gas chromatography–mass spectrometry

Cited by 71 publications

References 10 publications

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

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

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

Preparation of monoclonal antibody based indirect competitive ELISA for detecting 19-nortestosterone residue

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