Etgen A M, Martin M, Gilbert R, Lynch G
J Neurochem. 1980 Sep;35(3):598-602. doi: 10.1111/j.1471-4159.1980.tb03696.x.
Corticosterone significantly increases the incorporation of [3H]leucine into specific cytosol protein(s) isolated from in vitro hippocampal slices prepared from adult male albino rats. The present study showed that in slices coincubated with glucocorticoid plus a protein synthesis inhibitor (1 mM-cycloheximide), no such enhancement of amino acid incorporation was observed, suggesting that the hormone acts in the hippocampus to increase de novo protein synthesis. Further experiments demonstrated that the steroid-induced protein synthesis was first detectable (+ 5.7%) following a 30-min exposure of slices to corticosterone; slices incubated for 1 or 2 h both showed a 12% increase in synthesis of the affected protein(s) when compared with controls. In an attempt to determine whether the glucocorticoid alteration of protein metabolism was receptor-mediated, hippocampal slices were also incubated with 10 nM-progesterone, a steroid known to compete for corticosterone binding to its cytosol receptor. Progesterone alone, which does not translocate cytoplasmic receptors to the nucleus, did not alter hippocampal protein metabolism and effectively blocked the induction by corticosterone of the 54K protein(s). These studies provide evidence that in the rat hippocampus corticosterone interacts with high-affinity steroid receptors to regulate the synthesis of specific protein(s).
皮质酮能显著增加从成年雄性白化大鼠制备的体外海马切片中分离出的特定胞质溶胶蛋白对[3H]亮氨酸的掺入。本研究表明，在与糖皮质激素和蛋白质合成抑制剂（1 mM环己酰亚胺）共同孵育的切片中，未观察到氨基酸掺入的这种增强，这表明该激素在海马中起作用以增加从头蛋白质合成。进一步的实验表明，在切片暴露于皮质酮30分钟后，类固醇诱导的蛋白质合成首次可检测到（增加5.7%）；与对照组相比，孵育1或2小时的切片中受影响蛋白质的合成均增加了12%。为了确定蛋白质代谢的糖皮质激素改变是否是受体介导的，海马切片还与10 nM孕酮共同孵育，孕酮是一种已知能竞争皮质酮与其胞质溶胶受体结合的类固醇。单独的孕酮不会使细胞质受体转运到细胞核，也不会改变海马蛋白质代谢，并有效阻断皮质酮对54K蛋白的诱导。这些研究提供了证据，表明在大鼠海马中，皮质酮与高亲和力类固醇受体相互作用以调节特定蛋白质的合成。
