Document Detail

Steroids in equine testes: the identification of endogenous 19-hydroxy and 19-nor neutral steroids by gas chromatography--mass spectrometry.
MedLine Citation:
PMID:  2926297     Owner:  NLM     Status:  MEDLINE    
After homogenization of testicular tissue from stallions aged 1, 2 and 5 years, the unconjugated and conjugated steroids were isolated by a combined solvent-solid extraction procedure. The conjugates were further separated into glucuronides and sulphates by chromatography using Sephadex LH-20. After enzyme hydrolysis and solvolysis of the respective conjugate classes, the three extracts, unconjugated steroids, aglycones and solvolysed sulphates, were purified by chromatography using Kieselgel 60H columns. Five fractions were resolved from each extract; an aliquot of each fraction was derivatized to form the methoxime-trimethylsilyl ethers and the steroids were identified by combined gas chromatography-mass spectrometry. The results have shown that in stallion testes (1) steroidogenesis proceeds by both the 4-ene and the 5-ene pathways, (2) age-linked changes occur in both unconjugated and sulphoconjugated steroid fractions and (3) 19-hydroxy androgens and the 19-nor (C18) neutral steroids (19-norandrostenedione and 19-nortestosterone) are detected only in the unconjugated fraction whereas oestrene, the isomers of oestradiol and of 5(10)-oestrene-3,17-diol are the only steroids detected in the sulphoconjugate fraction. It is suggested that the unconjugated 19-oxygenated androgens present in stallion testes are converted to 19-nor neutral steroids by a reverse aldol reaction and a mechanism showing the putative intermediates in their formation is illustrated.
M C Dumasia; E Houghton; M Jackiw
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Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  The Journal of endocrinology     Volume:  120     ISSN:  0022-0795     ISO Abbreviation:  J. Endocrinol.     Publication Date:  1989 Feb 
Date Detail:
Created Date:  1989-04-25     Completed Date:  1989-04-25     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0375363     Medline TA:  J Endocrinol     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  223-9     Citation Subset:  IM    
Horseracing Forensic Laboratory Ltd., Newmarket, Suffolk.
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MeSH Terms
Age Factors
Androstanes / metabolism
Androstenes / metabolism
Estranes / metabolism
Estrenes / metabolism
Gas Chromatography-Mass Spectrometry
Horses / physiology*
Hydroxyprogesterones / metabolism
Nandrolone / metabolism*
Norsteroids / metabolism*
Steroids / metabolism*
Testis / physiology*
Reg. No./Substance:
0/Androstanes; 0/Androstenes; 0/Estranes; 0/Estrenes; 0/Hydroxyprogesterones; 0/Norsteroids; 0/Steroids; 434-22-0/Nandrolone

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