Danhaive P A, Rousseau G G
J Steroid Biochem. 1986 Feb;24(2):481-7. doi: 10.1016/0022-4731(86)90109-3.
The binding of ten steroids possessing antiglucocorticoid activity has been studied in rat skeletal muscle cytosol. The affinity of these steroids for both the androgen and the glucocorticoid receptors was determined by competition with radioactive R1881 (methyltrienolone, metribolone) and dexamethasone, respectively. The antiglucocorticoid activity of these compounds was assessed in rat hepatoma (HTC) cells by measuring their inhibitory effect on the glucocorticoid-induced tyrosine aminotransferase activity. This led to identification of five novel in vitro glucocorticoid antagonists. All the steroids tested bound to both the glucocorticoid and the androgen receptors in muscle. Four steroids had an affinity for the glucocorticoid receptor higher than for the androgen receptor. The assumption is made that the steroids tested also behave as antagonists when binding to the glucocorticoid receptor in muscle and behave as agonists when binding to the androgen receptor. On this basis, the data allow one to compute a potential anticatabolic (PAG) and a potential anabolic (PAA) index for each compound. These indices might be of predictive value to determine whether these steroids exert their anabolic action in muscle through the glucocorticoid receptor or through the androgen receptor. The data also make it unlikely that satellite cells are a preferential target for anabolic steroids in muscle.
在大鼠骨骼肌胞浆中研究了十种具有抗糖皮质激素活性的类固醇的结合情况。这些类固醇对雄激素受体和糖皮质激素受体的亲和力分别通过与放射性R1881（甲基三烯醇酮，美替勃龙）和地塞米松竞争来测定。通过测量这些化合物对糖皮质激素诱导的酪氨酸转氨酶活性的抑制作用，在大鼠肝癌（HTC）细胞中评估了它们的抗糖皮质激素活性。这导致鉴定出五种新型的体外糖皮质激素拮抗剂。所有测试的类固醇都与肌肉中的糖皮质激素受体和雄激素受体结合。四种类固醇对糖皮质激素受体的亲和力高于对雄激素受体的亲和力。据推测，测试的类固醇在与肌肉中的糖皮质激素受体结合时也表现为拮抗剂，而在与雄激素受体结合时表现为激动剂。在此基础上，这些数据允许计算每种化合物的潜在抗分解代谢（PAG）和潜在合成代谢（PAA）指数。这些指数对于确定这些类固醇是通过糖皮质激素受体还是通过雄激素受体在肌肉中发挥合成代谢作用可能具有预测价值。这些数据也使得卫星细胞不太可能是肌肉中合成代谢类固醇的优先靶标。
