Linked Life Data

15516291

Source:http://linkedlifedata.com/resource/pubmed/id/15516291

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2004-11-1
pubmed:abstractText
The most frequently used method to demonstrate testosterone abuse is the determination of the testosterone and epitestosterone concentration ratio (T/E ratio) in urine. Nevertheless, it is known that factors other than testosterone administration may increase the T/E ratio. In the last years, the determination of the carbon isotope ratio has proven to be the most promising method to help discriminate between naturally elevated T/E ratios and those reflecting T use. In this paper, an excretion study following oral administration of 40 mg testosterone undecanoate initially and 13 h later is presented. Four testosterone metabolites (androsterone, etiocholanolone, 5 alpha-androstanediol, and 5 beta-androstanediol) together with an endogenous reference (5 beta-pregnanediol) were extracted from the urines and the delta(13)C/(12)C ratio of each compound was analyzed by gas chromatography-combustion-isotope ratio mass spectrometry. The results show similar maximum delta(13)C-value variations (parts per thousand difference of delta(13)C/(12)C ratio from the isotope ratio standard) for the T metabolites and concomitant changes of the T/E ratios after administration of the first and the second dose of T. Whereas the T/E ratios as well as the androsterone, etiocholanolone and 5 alpha-androstanediol delta(13)C-values returned to the baseline 15 h after the second T administration, a decrease of the 5 beta-androstanediol delta-values could be detected for over 40 h. This suggests that measurements of 5 beta-androstanediol delta-values allow the detection of a testosterone ingestion over a longer post-administration period than other T metabolites delta(13)C-values or than the usual T/E ratio approach.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0146-4760
pubmed:author
pubmed:issnType
Print
pubmed:volume
28
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
426-31
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Urinary analysis of four testosterone metabolites and pregnanediol by gas chromatography-combustion-isotope ratio mass spectrometry after oral administrations of testosterone.
pubmed:affiliation
Laboratoire Suisse d'Analyse du Dopage, Institut Universitaire de Médecine Légale, Rue du Bugnon 21, 1005 Lausanne, Switzerland.
pubmed:publicationType
Journal Article, Clinical Trial, Research Support, Non-U.S. Gov't