Ichii S, Satoh Y, Izawa M, Iwasaki K
Endocrinol Jpn. 1984 Oct;31(5):583-94. doi: 10.1507/endocrj1954.31.583.
To examine the behavior in the receptor-acceptor system of glucocorticoids of different biopotencies, the stability of receptor complexes of dexamethasone (Dex), prednisolone (Pred) and corticosterone (Cort) in cytosols, nuclei and nuclear extracts from the rat liver was compared. Receptor complexes bound to these ligands were relatively stable at 0 degrees C, but at 25 degrees C a rapid liberation of ligands was observed. However, differences in the rate of temperature-dependent decay of these receptor complexes were obvious; the Dex receptor complex was the most stable, the receptor complex bound to Cort liberated the ligand most rapidly and the stability of the Pred-receptor complex was the intermediate of these two. The addition of molybdate and dithiothreitol stabilized the receptor complexes in cytosols but these agents accelerated the liberation of ligands from the complexes in nuclei and nuclear extracts. Among the factors examined, only bovine serum albumin decreased the rate of decay in the nuclear-bound receptor complexes. From these observations, it appears likely that different mechanisms may contribute to the dissociation of ligand from receptor complexes in cytosols, nuclei and nuclear extracts.
为了研究不同生物活性的糖皮质激素在受体 - 受体系统中的行为，比较了地塞米松（Dex）、泼尼松龙（Pred）和皮质酮（Cort）在大鼠肝脏胞质溶胶、细胞核和核提取物中的受体复合物稳定性。与这些配体结合的受体复合物在0℃时相对稳定，但在25℃时观察到配体迅速释放。然而，这些受体复合物的温度依赖性衰变速率存在明显差异；Dex受体复合物最稳定，与Cort结合的受体复合物释放配体最快，Pred - 受体复合物的稳定性介于两者之间。钼酸盐和二硫苏糖醇的添加使胞质溶胶中的受体复合物稳定，但这些试剂加速了细胞核和核提取物中复合物配体的释放。在所研究的因素中，只有牛血清白蛋白降低了核结合受体复合物的衰变速率。从这些观察结果来看，似乎不同的机制可能导致配体从胞质溶胶、细胞核和核提取物中的受体复合物解离。
