Studies related to the metabolism of anabolic steroids in the horse: the identification of some 16-oxygenated metabolites of 19-nortestosterone

Houghton, E.; Dumasia, M. C.

doi:10.3109/00498258009033771

Cited by 49 publications

(32 citation statements)

References 7 publications

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“…15 Following addition of internal standard ([ 2 H]5b-androstan-3a,17b-diol; 200 ng ml 21 ), bile samples were adjusted to pH 6.8 and conjugated material was hydrolysed by incubation with E. coli b-glucuronidase (2000 units; 2 h at 50°C). Hydrolysed samples (5 ml) were then extracted on preconditioned (methanol, 5 ml, then water, 5 ml) C 18 Sep Pak Vac solid-phase cartridges (500 mg, 6 ml) (Waters, Watford, UK), and the cartridges were washed with water (5 ml) and then hexane (5 ml), drying the cartridges at each stage. Analytes were eluted with diethyl ether (5 ml).…”

Section: Extraction Of Bile Samples For Gc-ms Analysismentioning

confidence: 99%

“…Urine samples (30 ml) were acidified with formic acid (6 ml), and bile (1 ml) samples were diluted with three volumes of 0.02% v/v formic acid, prior to concentration on to preconditioned (methanol, 10 ml, then 0.02% formic acid, 2 3 10 ml) C 18 Mega Bond Elut cartridges (Varian, Walton on Thames, UK). Cartridges were washed three times with water (10 ml) and the extracts eluted with methanol (10 ml).…”

Section: Extraction Of Urine and Bile Samples For Hplc Analysismentioning

confidence: 99%

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Residues and metabolism of 19-nortestosterone laurate in steers†

Sauer¹,

Howells²,

Bellworthy³

et al. 1998

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The illegal use of nandrolone) and its esters in livestock, for growth promotion purposes, has been widely reported in the European Union. The target residues for surveillance of abuse in bovine urine and bile samples are 17a-and 17b-19NT, although this choice of target residues is not based on in vivo radiotracer biotransformation data. In this study, four steers were administered [ 3 H 2 ]-and [ 2 H 3 ] 17b-19NT laurate (2 mg kg 21 body mass) by intramuscular injection and blood, urine, faeces and bile samples were taken for 30 d until slaughter, after which tissues were sampled for total residue analysis. Total plasma radiolabelled residues reached a maximum of 56.3 ± 15.9 pmol ml 21 at 36 h and were still appreciable (13.3 ± 1.6 pmol ml 21 ) 30 d after treatment. Throughout the study period, total residue concentrations in bile (about 2-16 nmol ml 21 ), urine and faeces (0.5-3 nmol ml 21 or g 21 ) were higher than in other tissues sampled at slaughter. At slaughter there was evidence of residue accumulation in pigmented eye tissue (33.1 ± 6.1 pmol g 21 ) and in white (13.4 ± 3.4 pmol g 21 ) and black hair (28.9 ± 8.9 pmol g 21 ). Evaluation of radio-HPLC profiles of urine and bile extracts generally indicated that 19NT and 19NT laurate residues were present in relatively small amounts among a complex mixture of metabolites. GC-MS analysis of glucuronidase-hydrolysed bile extracts indicated that the major metabolites were 5b-estrane-3a,17a-diol, 5a-estrane-3b,17a-diol, 5a-estran-3a-ol-17-one (norandrosterone) and estra-1,3,5(10)-triene-3,17a-diol (17a-estradiol).

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Section: Extraction Of Bile Samples For Gc-ms Analysismentioning

confidence: 99%

Section: Extraction Of Urine and Bile Samples For Hplc Analysismentioning

confidence: 99%

Residues and metabolism of 19-nortestosterone laurate in steers†

Sauer¹,

Howells²,

Bellworthy³

et al. 1998

Analyst

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“…8,9 ABA, another important metabolite of 17bN in other species, [9][10][11][12][13][14][15][16][17][18] was not detected in boars. It is worth noting the variability in the concentrations obtained for the different animals.…”

Section: Discussionmentioning

confidence: 99%

“…[7][8][9][10][11][12][13][14][15][16][17][18][19][20] The structures of 17bN and its metabolites identified in different species are presented in Fig. 1.…”

mentioning

confidence: 99%

“…1 In horses, isomers of estranediol (mainly 5a-estrane-3b,17a-diol (ABA) and 5a-estrane-3b, 17b-diol (ABB)) and the metabolite resulting from epimerization at the C 17 position, 17a-nortestosterone (17aN), have been detected as main metabolites, 17a isomers mainly in the glucuronide fraction and 17b isomers mainly in the sulphate fraction. [7][8][9][10][11][12][13] In bovines, 17aN, ABA and NorE have also been detected as main metabolites in cows and calves. [14][15][16][17][18] 17bN, isomers of 3-hydroxyestran-17-one (NorA, NorE, NorEpiA) and isomers of estrane-3,17-diol (BAB and ABB) have been identified in miniature pigs after the administration of 17bN laurate.…”

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Detection of the administration of 17β‐nortestosterone in boars by gas chromatography/mass spectrometry

Ventura

Roig

Pérez

et al. 2008

Rapid Comm Mass Spectrometry

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17beta-Nortestosterone (17betaN) is illegally used in livestock as a growth promoter and its endogenous production has been described in some animals, such as adult boars. In this paper, the metabolism of 17betaN in boars has been studied by gas chromatography/mass spectrometry (GC/MS) in order to identify markers of the exogenous administration. Administration studies of intramuscular 17betaN laurate to male pigs were performed. Free, sulphate and glucuronide fractions of the urine samples were separated and the steroids present were quantified by GC/MS. 17betaN was detected in some pre-administration samples. After administration, 17betaN, norandrosterone, noretiocholanolone (NorE), norepiandrosterone, 5beta-estrane-3alpha,17beta-diol and 5alpha-estrane-3beta,17beta-diol were detected in different fractions, being the most important metabolites, 17betaN excreted as a sulphate and free NorE. Samples collected in routine controls were also analyzed by GC/MS to identify endogenous compounds. 17betaN, norandrostenedione and estrone were detected in almost all the samples. No other 17betaN metabolites were detected. According to these results, the detection by GC/MS of some of the 17betaN metabolites described above, different from 17betaN, could be indicative of the exogenous administration of 17betaN to boars.

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Capillary column gas chromatographic mass spectrometric analysis of anabolic steroid residues using splitless injections made at elevated temperatures

Houghton¹,

Teale²

1981

Biol. Mass Spectrom.

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The use of capillary column gas chromatography mass spectrometry has been investigated for the detection of the presence of estrane-3,17 alpha-diol in horse urine extracts; the detection of this diol confirms the administration of anabolic steroids based upon 19-nortestosterone. To reduce analysis time, but yet maintain a solvent effect in the splitless injection mode, injections have been made at elevated temperatures (190-220 degree C) using high boiling solvents (dodecane b.p. 214 degree C and tetradecane b.p. 252 degree C).

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Studies related to the metabolism of anabolic steroids in the horse: the identification of some 16-oxygenated metabolites of 19-nortestosterone

Cited by 49 publications

References 7 publications

Residues and metabolism of 19-nortestosterone laurate in steers†

Residues and metabolism of 19-nortestosterone laurate in steers†

Detection of the administration of 17β‐nortestosterone in boars by gas chromatography/mass spectrometry

Capillary column gas chromatographic mass spectrometric analysis of anabolic steroid residues using splitless injections made at elevated temperatures

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