Coutard M, Duval D, Osborne-Pellegrin M J
J Steroid Biochem. 1987 Jul;28(1):29-34. doi: 10.1016/0022-4731(87)90120-8.
The binding sites for [3H]corticosterone (3HB) and [3H]aldosterone (3HA) within the hippocampal area of the mouse brain have been studied by autoradiography in competition experiments. Excess unlabelled aldosterone (A) or corticosterone (B) both abolished the nuclear accumulation of radioactivity within neurons observed after injection of either 3HA or 3HB. Experiments where a subcutaneous injection of a "pure glucocorticoid' RU26988 was given before injection of 3HA alone showed a marked accumulation of radioactivity within neuronal nuclei of the hippocampus suggesting the presence of 3HA binding sites distinct from classical type II glucocorticoid receptors. In addition, when RU26988 was given before the injection of 3HA associated with a 30- or 100-fold excess of either A or B, the cell nuclear accumulation of radioactivity was no longer observed. These results showed that in our in vivo experimental conditions, B displayed the same ability as A to occupy 3HA binding sites, supporting the view that in mouse hippocampal neuronal nuclei, the aldosterone-binding and corticosterone-preferring sites represent the same molecular entity.
通过放射自显影竞争实验，研究了小鼠脑海马区域内[3H]皮质酮（3HB）和[3H]醛固酮（3HA）的结合位点。过量未标记的醛固酮（A）或皮质酮（B）均消除了注射3HA或3HB后观察到的神经元内放射性核积累。在单独注射3HA前皮下注射“纯糖皮质激素”RU26988的实验中，海马神经元核内出现明显的放射性积累，提示存在不同于经典II型糖皮质激素受体的3HA结合位点。此外，当在注射与30倍或100倍过量A或B相关的3HA前给予RU26988时，不再观察到放射性的细胞核积累。这些结果表明，在我们的体内实验条件下，B与A占据3HA结合位点的能力相同，支持了在小鼠海马神经元核中，醛固酮结合位点和皮质酮优先结合位点代表同一分子实体的观点。
