Drug Test Anal. 2011 Jan;3(1):74-87. doi: 10.1002/dta.250.
Detection of androgenic-anabolic steroid abuse in equine sports requires knowledge of the drug's metabolism in order to target appropriate metabolites, especially where urine is the matrix of choice. Studying 'designer' steroid metabolism is problematic since it is difficult to obtain ethical approval for in vivo metabolism studies due to a lack of toxicological data. In this study, the equine in vitro metabolism of eight steroids available for purchase on the Internet is reported; including androsta-1,4,6-triene-3,17-dione, 4-chloro,17α-methyl-androsta-1,4-diene-3,17β-diol, estra-4,9-diene-3,17-dione, 4-hydroxyandrostenedione, 20-hydroxyecdysone, 11-keto-androstenedione, 17α-methyldrostanolone, and tetrahydrogestrinone. In order to allow for retrospective analysis of sample testing data, the use of a high-resolution (HR) accurate-mass Thermo LTQ-Orbitrap liquid chromatography-mass spectrometry (LC-MS) instrument was employed for metabolite identification of underivatized sample extracts. The full scan LC-HRMS Orbitrap data were complimented by LC-HRMS/MS and gas-chromatography-mass spectrometry (GC-MS) experiments in order to provide fragmentation information and to ascertain whether GC-MS was capable of detecting any metabolite not detected by LC-HRMS. With the exception of 20-hydroxyecdysone, all compounds were found to be metabolized by equine liver S9 and/or microsomes. With the exception of 17α-methyldrostanolone, which produced metabolites that could only be detected by GC-MS, the metabolites of all other compounds could be identified using LC-HRMS, thus allowing retrospective analysis of previously acquired full-scan data resulting from routine equine drug testing screens. In summary, while in vitro techniques do not serve as a replacement for more definitive in vivo studies in all situations, their use does offer an alternative in situations where it would not be ethical to administer untested drugs to animals.
检测马体育比赛中的合成代谢类固醇滥用需要了解药物在体内的代谢情况，以便针对适当的代谢产物，特别是在尿液是首选基质的情况下。由于缺乏毒理学数据，因此很难获得用于体内代谢研究的伦理批准，因此研究“设计”类固醇代谢是有问题的。在这项研究中，报告了在互联网上购买的八种类固醇在马体内的体外代谢情况；包括雄甾-1,4,6-三烯-3,17-二酮、4-氯、17α-甲基-雄甾-1,4-二烯-3,17β-二醇、雌甾-4,9-二烯-3,17-二酮、4-羟基雄酮、20-羟基蜕皮甾酮、11-酮-雄烯二酮、17α-甲基雄烯酮和四氢孕甾酮。为了允许对样品测试数据进行回顾性分析，使用高分辨率（HR）精确质量 Thermo LTQ-Orbitrap 液相色谱-质谱（LC-MS）仪器对未衍生的样品提取物进行代谢产物鉴定。全扫描 LC-HRMS Orbitrap 数据通过 LC-HRMS/MS 和气相色谱-质谱（GC-MS）实验进行补充，以提供碎片信息，并确定 GC-MS 是否能够检测到 LC-HRMS 未检测到的任何代谢产物。除 20-羟基蜕皮甾酮外，所有化合物均被马肝 S9 和/或微粒体代谢。除 17α-甲基雄烯酮产生的代谢产物只能通过 GC-MS 检测到外，所有其他化合物的代谢产物均可通过 LC-HRMS 鉴定，从而允许对先前通过常规马药物检测筛选获得的全扫描数据进行回顾性分析。总之，虽然在所有情况下，体外技术都不能替代更明确的体内研究，但在对动物施用未经测试的药物在伦理上不可行的情况下，它们的使用确实提供了一种替代方法。
