Racing Laboratory, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, N.T., Hong Kong, China.
Drug Test Anal. 2013 Feb;5(2):81-8. doi: 10.1002/dta.1380. Epub 2012 Jun 20.
1-Testosterone (17β-hydroxy-5α-androst-1-en-3-one), a synthetic anabolic steroid, has been described as one of the most effective muscle-building supplements currently on the market. It has an anabolic potency of 200 as compared to 26 for testosterone. Apart from its abuse in human sports, it can also be a doping agent in racehorses. Metabolic studies on 1-testosterone have only been reported for human in the early seventies, whereas little is known about its metabolic fate in horses. This paper describes the studies of in vitro and in vivo metabolism of 1-testosterone in horses, with the aim of identifying the most appropriate target metabolites to be monitored for controlling the misuse or abuse of 1-testosterone in racehorses. Six in vitro metabolites, namely 5α-androst-1-ene-3α,17β-diol (T1a), 5α-androstane-3β,17β-diol (T2), epiandrosterone (T3), 16,17-dihydroxy-5α-androst-1-ene-3-one (T4 & T5), and 5α-androst-1-ene-3,17-dione (T6), were identified. For the in vivo studies, two thoroughbred geldings were each administered orally with 800 mg of 1-testosterone by stomach tubing. The results revealed that the parent drug and eight metabolites were detected in urine. Besides the four in vitro metabolites (T1a, T2, T3, and T5), four other urinary metabolites, namely 5α-androst-1-ene-3β,17α-diol (T1b), 5α-androst-1-ene-3β,17β-diol (T1c), 5α-androstane-3α,17α-diol (T7) and 5α-androstane-3β,17α-diol (T8) were identified. This study shows that the detection of 1-testosterone administration is best achieved by monitoring the parent drug, which could be detected for up to 30 h post-administration.
1-睾酮（17β-羟基-5α-雄甾-1-烯-3-酮）是一种合成的同化类固醇，被描述为目前市场上最有效的肌肉增强补充剂之一。它的同化效力为 200，而睾酮为 26。除了在人类运动中的滥用外，它还可以作为赛马的兴奋剂。早在 70 年代就有关于 1-睾酮的代谢研究仅在人类中报道，而对其在马中的代谢命运知之甚少。本文描述了 1-睾酮在马体内外代谢的研究，旨在确定最适合监测的靶代谢物，以控制 1-睾酮在赛马中的误用或滥用。鉴定了 6 种体外代谢物，即 5α-雄甾-1-烯-3α,17β-二醇（T1a）、5α-雄烷-3β,17β-二醇（T2）、表雄酮（T3）、16,17-二羟基-5α-雄甾-1-烯-3-酮（T4 和 T5）和 5α-雄甾-1-烯-3,17-二酮（T6）。对于体内研究，用胃管给 2 匹纯血种公马口服 800mg 的 1-睾酮。结果表明，在尿液中检测到母体药物和 8 种代谢物。除了 4 种体外代谢物（T1a、T2、T3 和 T5）外，还鉴定出 4 种其他尿代谢物，即 5α-雄甾-1-烯-3β,17α-二醇（T1b）、5α-雄甾-1-烯-3β,17β-二醇（T1c）、5α-雄烷-3α,17α-二醇（T7）和 5α-雄烷-3β,17α-二醇（T8）。本研究表明，通过监测母体药物，最好实现对 1-睾酮给药的检测，给药后最多可检测到 30 小时。
