Liesegang P, Romalo G, Sudmann M, Wolf L, Schweikert H U
Department of Internal Medicine, University of Bonn, Germany.
J Androl. 1994 May-Jun;15(3):194-9.
Glucocorticoids, androgens, estrogens and 1 alpha,25-dihydroxycholecalciferol (1 alpha,25-(OH)2D3) exert a variety of effects on bone homeostasis. We have measured the receptors for these hormones in cultured human osteoblast-like cells. Specific binding was found with each of the four steroids tested, namely maximum binding capacities, Bmax, of 2,581 (1,368-4,223), 146 (101-237), 176 (20-552), and 387 (290-620) fmol.mg DNA-1 (mean, range) for [3H]dexamethasone, [3H]5 alpha-dihydrotestosterone, [3H]17 beta-estradiol ([3H]E2), and [3H]1 alpha,25-(OH)2D3, respectively. The corresponding apparent dissociation constants were 13.3 (9.2-22.2), 0.43 (0.23-0.94), 0.45 (0.17-0.88), and 0.020 (0.008-0.030) nM, respectively. Both high-affinity, low-capacity and low-affinity, high-capacity specific [3H]E2 binding were demonstrable. In conclusion, we could demonstrate that human osteoblast-like cells contain specific glucocorticoid receptors. In addition specific androgen, estrogen, and 1 alpha,25-(OH)2D3 binding was demonstrated. These cells contain several times more binding sites for dexamethasone than for dihydrotestosterone, estradiol, and 1 alpha,25-(OH)2D3, a feature that might contribute to the marked sensitivity of human bone to glucocorticoids.
糖皮质激素、雄激素、雌激素和1α,25 - 二羟胆钙化醇（1α,25-(OH)₂D₃）对骨稳态有多种影响。我们已在培养的人成骨细胞样细胞中检测了这些激素的受体。在所测试的四种类固醇中均发现了特异性结合，即[³H]地塞米松、[³H]5α - 双氢睾酮、[³H]17β - 雌二醇（[³H]E₂）和[³H]1α,25-(OH)₂D₃的最大结合容量Bmax分别为2581（1368 - 4223）、146（101 - 237）、176（20 - 552）和387（290 - 620）fmol·mg DNA⁻¹（平均值，范围）。相应的表观解离常数分别为13.3（9.2 - 22.2）、0.43（0.23 - 0.94）、0.45（0.17 - 0.88）和0.020（0.008 - 0.030）nM。高亲和力、低容量和低亲和力、高容量的特异性[³H]E₂结合均可被证实。总之，我们能够证明人成骨细胞样细胞含有特异性糖皮质激素受体。此外，还证实了特异性雄激素、雌激素和1α,25-(OH)₂D₃结合。这些细胞中地塞米松的结合位点比双氢睾酮、雌二醇和1α,25-(OH)₂D₃的结合位点多几倍，这一特征可能有助于人类骨骼对糖皮质激素的显著敏感性。
