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Anabolic Steroids. Testosterone Endogenous steroid hormone. Androstenedione “Andro” Testosterone precursor Used by Mark McGuire. Nandrolone Previously used for osteoporosis Used by Linford Christie. Tetrahydrogestrinone (THG, “The Clear”) Used by Marion Jones, Jason Giambi
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Anabolic Steroids Testosterone Endogenous steroid hormone Androstenedione “Andro” Testosterone precursor Used by Mark McGuire Nandrolone Previously used for osteoporosis Used by Linford Christie Tetrahydrogestrinone (THG, “The Clear”) Used by Marion Jones, Jason Giambi BALCO (Victor Conte) scandal
T/E Ratio Measured to Determine Doping Epitestosterone (E) Inactive though present naturally in adult males Ca. 1:1 ratio T/E (variable) Testosterone (T) Testosterone/epitestosterone (T/E) ratio in urine is tested by GC-MS. Excess of 6:1 is considered “doping.” Administration of testosterone does not affect the levels of epitestosterone. Epitestosterone is banned in competitive sports, even though it’s inactive. Why?
Gas Chromatography (GC) Spectrum of Testosterone Derivatives Reference samples Analyte (other components present) Muller et al. J. Chromatography A.1999, p 275
Reference Samples Required for GC-MS and LC-MS Analysis THG was designed and synthesized to evade detection, since reference sample (analytical standard) was lacking. Used syringe with “The Clear” (THG) submitted to USADA for analytical testing. Tetrahydrogestrinone (THG, “The Clear”) Gestrinone Known anabolic steroid Prescribed for endometriosis MS fragmentation showed peaks 4 amu higher than gestrinone