Coutard M, Osborne-Pellegrin M J, Funder J
Cell Tissue Res. 1979 Aug;200(2):311-22. doi: 10.1007/BF00236423.
Autoradiograms of mouse pituitaries were prepared 30 min after injection of 3H-dexamethasone (3HDM), 3H-corticosterone (3HB) and 3H-cortexolone (3HS) either alone or in the presence of competing unlabelled steroids. 3H-dexamethasone accumulated in cell nuclei of both the pars distalis and the pars nervosa but not in those of the pars intermedia. This preferential accumulation (nuclear/cytoplasmic grain density, 4 : 1) was abolished by the concurrent administration of excess dexamethasone. 3H-corticosterone, to a much less marked extent than 3H-dexamethasone, accumulated in cell nuclei of the pars distalis but not in those of the pars intermedia and the pars nervosa. Excess unlabelled corticosterone diminished nuclear grain density in the pars distalis. After 3-h-cortexolone injection, preferential nuclear uptake was not observed. In a second series of experiments, excess dexamethasone (10 x, 100 x), corticosterone (100 x, 300 x) and cortexolone (100 x, 300 x) administered with 3H-dexamethasone were without effect on cytoplasmic grain density but totally abolished preferential nuclear accumulation. Parallel biochemical studies on kidney cytoplasmic preparations from the same animals showed no differences in total cytoplasmic radioactivity between treatments but marked differences in cytoplasmic bound 3H-dexamethasone. The results demonstrate: i) that dexamethasone binds specifically to cell nuclei of the pars distalis and the pars nervosa and that this nuclear concentration is abolished by competing corticosterone and cortexolone as well as dexamethasone; ii) that corticosterone localizes in cell nuclei of the pars distalis but much less markedly than dexamethasone; iii) that cortexolone fullfils the criteria of a glucocorticoid antagonist at the pituitary cell level.
在注射³H-地塞米松（³H-DM）、³H-皮质酮（³H-B）和³H-皮质素（³H-S）后30分钟制备小鼠垂体的放射自显影片，注射时这些激素单独使用或在有竞争性未标记类固醇存在的情况下使用。³H-地塞米松在远侧部和神经部的细胞核中蓄积，但在中间部的细胞核中不蓄积。这种优先蓄积（核/质颗粒密度为4:1）在同时给予过量地塞米松时被消除。³H-皮质酮在远侧部细胞核中的蓄积程度远低于³H-地塞米松，在中间部和神经部的细胞核中不蓄积。过量未标记的皮质酮降低了远侧部的核颗粒密度。注射³H-皮质素3小时后，未观察到优先的核摄取。在第二系列实验中，与³H-地塞米松一起给予过量的地塞米松（10倍、100倍）、皮质酮（100倍、300倍）和皮质素（100倍、300倍）对细胞质颗粒密度没有影响，但完全消除了优先的核蓄积。对同一动物肾脏细胞质制剂进行的平行生化研究表明，各处理之间总细胞质放射性没有差异，但细胞质结合的³H-地塞米松有显著差异。结果表明：i）地塞米松特异性结合远侧部和神经部的细胞核，这种核内浓度可被竞争性的皮质酮、皮质素以及地塞米松消除；ii）皮质酮定位于远侧部的细胞核中，但程度远低于地塞米松；iii）皮质素在垂体细胞水平符合糖皮质激素拮抗剂的标准。
