URINARY PROFILE OF ANDROGEN METABOLITES AT DIFFERENT STAGES OF PUBERTAL DEVELOPMENT IN A POPULATION OF SPORTING MALE-SUBJECTS

In this cross-sectional study on 140 subjects, several testosterone and epitestosterone metabolites have been analyzed by gas chromatography-mass spectrometry associated with stable isotope dilution, a technique requested for doping analysis in general, and detection of exogenous testosterone supply in particular. Urinary excretions of luteinizing hormone, testosterone and epitestosterone glucoronides and sulfates, as well as glucuronides of 5-androstene-3 beta, 17 alpha-diol, 5 alpha- and 5 beta-androstane-3 alpha, 17 alpha-diol and the corresponding 17 beta-isomers, present similar patterns of increase throughout pubertal development, from stage 1 up to stage 5. Excretion levels are significantly different in general between stages 1, 2, 3 and 4, the highest percentage increase being observed between stages 3 and 4. None of the ratios of testosterone to epitestosterone glucuronides are beyond the threshold value of 6, where testosterone abuse by athletes is suspected. No particular pubertal stage exceeded this critical value with a probability higher than p = 0.006, a value that was determined on the whole population. This is consistent with the non-significant differences between correlation slopes of regression curves, relating either testosterone or epitestosterone glucuronide to chronological age. The ratio of testosterone glucuronide to luteinizing hormone increases significantly throughout puberty and this might be a limitation to the widespread use of this ratio for the detection of testosterone misuse. Other ratios, such as testosterone glucuronide to epitestosterone (glucuronide + sulfate), glucuronides of testosterone to 5-androstene-3 beta, 17 alpha-diol, glucuronides of epitestosterone to 5-androstene-3 beta, 17 alpha-diol and epitestosterone glucuronide to sulfate, which have been suggested as efficient complementary criteria for the detection of testosterone and/or epitestosterone self-administration have non-significant interstage variability, except between stages 3 and 4.