ABSTRACT
<p><b>AIM</b>To establish a method to determine the isotope ratios of 13C to 12C of dehydroepiandrosterone and its metabolites in urine, for detecting the source of dehydroepiandrosterone or its metabolites.</p><p><b>METHODS</b>Preliminary separation of endogenous anabolic androgenic steroids could be achieved using solid phase extraction, enzymolysis and thin layer chromatography. The source of dehydroepiandrosterone and other endogenous anabolic androgenic steroids could be detected by their delta values with gas chromat ography-combustion-isotope ratio mass spectrometry.</p><p><b>RESULTS</b>The 5 values of some metabolites of dehydroepiandrosterone reduced after the administration of dehydroepiandrosterone preparation. In these cases the data indicated that exogenous anabolic androgenic steroids were administrated.</p><p><b>CONCLUSION</b>The source of dehydroepiandrosterone or its metabolites in urine could be detected by measuring their delta values with this method.</p>