Danhaive P A, Rousseau G G
Faculté de Médecine Vétérinaire, Université de Liège, Belgium.
J Steroid Biochem. 1988 Jun;29(6):575-81. doi: 10.1016/0022-4731(88)90154-9.
The muscle anabolic/anti-catabolic activity of the androgenic steroids testosterone and trenbolone was studied in rats to investigate whether such steroids act as agonists via muscle androgen receptors, or as antagonists that oppose the catabolic effects of endogenous glucocorticoids via their interaction with muscle glucocorticoid receptors. For comparison, the effects of the potent glucocorticoid antagonist RU486 were also examined. The parameters measured included growth rate, muscle weight, serum growth hormone and corticosterone levels, and receptor binding parameters in muscle cytosol. Females responded better than males to anabolic treatment with the androgenic steroids. Ovariectomy or adrenalectomy abolished this response. Neither the sex difference nor the requirement for ovaries or adrenals could be explained in terms of muscle receptor parameters or serum growth hormone levels. The muscle anabolic activity of androgenic steroids was restored when castrated males were treated with oestradiol and when adrenalectomized females were treated with corticosterone. RU486 also prevented the catabolic/anti-anabolic activity of exogenous corticosterone in adrenalectomized rats. Testosterone and RU486 behaved as anti-glucocorticoids in vivo since they inhibited glucocorticoid-induced liver tyrosine aminotransferase activity. The results suggest that anabolic steroids can act via muscle glucocorticoid receptors, thereby antagonizing the catabolic activity of endogenous glucocorticoids, rather than via muscle androgen receptors.
研究了雄激素类固醇睾酮和群勃龙的肌肉合成代谢/抗分解代谢活性，以调查此类类固醇是通过肌肉雄激素受体起激动剂作用，还是作为拮抗剂通过与肌肉糖皮质激素受体相互作用来对抗内源性糖皮质激素的分解代谢作用。为作比较，还检测了强效糖皮质激素拮抗剂RU486的作用。所测量的参数包括生长速率、肌肉重量、血清生长激素和皮质酮水平，以及肌肉细胞溶胶中的受体结合参数。雌性对雄激素类固醇的合成代谢治疗反应比雄性更好。卵巢切除或肾上腺切除消除了这种反应。无论是性别差异还是对卵巢或肾上腺的需求，都无法用肌肉受体参数或血清生长激素水平来解释。当阉割的雄性用雌二醇治疗以及肾上腺切除的雌性用皮质酮治疗时，雄激素类固醇的肌肉合成代谢活性得以恢复。RU486也可防止肾上腺切除大鼠中外源皮质酮的分解代谢/抗合成代谢活性。睾酮和RU486在体内表现为抗糖皮质激素，因为它们抑制糖皮质激素诱导的肝脏酪氨酸转氨酶活性。结果表明，合成代谢类固醇可通过肌肉糖皮质激素受体起作用，从而对抗内源性糖皮质激素的分解代谢活性，而不是通过肌肉雄激素受体。
