Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Más filtros

Bases de datos
Tipo del documento
Intervalo de año de publicación
1.
Endocrinol Metab Clin North Am ; 39(1): 45-57, viii, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20122449

RESUMEN

Testosterone is the principal male sex hormone. As with all natural steroids, it is biosynthesized from cholesterol. Phase I metabolism employs some very specific enzymes and pathways. Phase II metabolism and excretion follow more general patterns. The effects of testosterone are twofold: anabolic and androgenic. Because of its anabolic effects, testosterone is frequently abused in sports. Because of its endogenous nature, testosterone doping is difficult to detect. The standard procedure is based on the evaluation of the urinary steroid profile. Conspicuous samples then are submitted to compound-specific (13)C/(12)C analysis. Synthetic and endogenous steroids differ in this measure. Numerous xenobiotic compounds have been derived from testosterone. The modifications typically aim at a reduction of the androgenic properties while maintaining the anabolic potential. Most of these compounds have been withdrawn from the legal market. However, they are found to be illicitly added to otherwise inefficient nutritional supplements. These products represent a major problem to doping control. Recently, clinical trials with selective androgen receptor modulators have been started.


Asunto(s)
Anabolizantes , Doping en los Deportes , Anabolizantes/administración & dosificación , Anabolizantes/efectos adversos , Anabolizantes/síntesis química , Atletas , Rendimiento Atlético/fisiología , Deshidroepiandrosterona/administración & dosificación , Deshidroepiandrosterona/efectos adversos , Suplementos Dietéticos , Doping en los Deportes/prevención & control , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Isótopos/análisis , Masculino , Nandrolona/administración & dosificación , Testosterona/administración & dosificación , Testosterona/efectos adversos , Testosterona/fisiología
2.
Handb Exp Pharmacol ; (195): 155-85, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20020364

RESUMEN

Anabolic steroids have been studied for over 50 years and during that time numerous compounds with a variety of functional groups have been produced and many have been published. Of these only a small number have been introduced to the pharmaceutical market. WADA has continued the work begun by the IOC banning the use of these agents within sport as performance enhancing substances. Athletes, however, continue to use these anabolic steroids but tighter testing and the introduction of unannounced sample collection has made this form of cheating harder.In order to try to evade detection, athletes who continue to dope are having to resort to the use of a far more dangerous form of drug - the designer steroid. These steroids are manufactured to closely resemble existing known compounds, but with sufficient chemical diversity to ensure that their detection by the WADA accredited laboratories is more difficult. A worrying feature of the use of these compounds is that no data is available to evaluate either the efficacy or the safety of these substances. Many such drugs are now being made in clandestine ways (as demonstrated by the recent BALCO case) and then passed on to athletes who become the guinea pigs determining the potential of the substances as doping agents.Methods for the detection of these new compounds are being developed using emerging techniques such as gas chromatography or liquid chromatography attached to a variety of mass spectrometry instruments. This technology as well as vigilance by laboratories and enforcement agencies can all help in early detection of designer steroids being used for doping.


Asunto(s)
Anabolizantes/química , Anabolizantes/farmacología , Drogas de Diseño/química , Drogas de Diseño/farmacología , Doping en los Deportes/métodos , Esteroides/química , Esteroides/farmacología , Anabolizantes/síntesis química , Animales , Cromatografía Liquida , Drogas de Diseño/síntesis química , Suplementos Dietéticos , Cromatografía de Gases y Espectrometría de Masas , Humanos , Espectrometría de Masas , Esteroides/síntesis química
3.
Endocrinology ; 150(12): 5606-16, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19854864

RESUMEN

We identified a novel synthetic steroid, S42, as a promising candidate of selective androgen receptor (AR) modulator. Results of the whole-cell binding assay using COS-7 cells exogenously expressing various steroid receptors indicated that S42 specifically binds to AR and progesterone receptor. When orchiectomized Sprague Dawley rats were administered with S42 for 3 wk, the muscle weight of the levator ani was increased as markedly as that induced by 5alpha-dihydrotestosterone (DHT), but the weight of the prostate was not elevated at any doses in contrast to DHT. The plasma concentrations of gonadotropin and adiponectin, those down-regulated by DHT, were unaffected by S42. In addition, although the plasma triglyceride level was unaffected by DHT, it was significantly reduced by S42. This effect of S42 was associated with suppression of the SRBP-1c-mediated lipogenic and insulin-desensitizing pathway in the liver and visceral fat. Taken together, S42 works as an AR agonist in muscle and as an AR antagonist in the prostate, pituitary gland, and liver, accompanying beneficial potentials on lipid metabolism.


Asunto(s)
Próstata/metabolismo , Receptores Androgénicos/metabolismo , Esteroides/metabolismo , Células 3T3-L1 , Anabolizantes/síntesis química , Anabolizantes/metabolismo , Anabolizantes/farmacología , Antagonistas de Receptores Androgénicos , Andrógenos , Animales , Unión Competitiva , Células COS , Línea Celular Tumoral , Chlorocebus aethiops , Evaluación Preclínica de Medicamentos , Humanos , Grasa Intraabdominal/efectos de los fármacos , Grasa Intraabdominal/metabolismo , Ligandos , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones , Estructura Molecular , Células 3T3 NIH , Orquiectomía , Tamaño de los Órganos/efectos de los fármacos , Próstata/efectos de los fármacos , Próstata/crecimiento & desarrollo , Ratas , Ratas Sprague-Dawley , Esteroides/síntesis química , Esteroides/farmacología , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Triglicéridos/sangre , Triglicéridos/metabolismo
4.
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA