Gould E, Woolley C S, McEwen B S
Laboratory of Neuroendocrinology, Rockefeller University, New York, NY 10021.
Neuroscience. 1990;37(2):367-75. doi: 10.1016/0306-4522(90)90407-u.
In order to determine whether short-term glucocorticoid manipulations influence the morphology and survival of neurons in the adult mammalian hippocampal formation, we performed quantitative analyses of Golgi-impregnated and Nissl-stained tissue from the brains of sham operated male rats, adrenalectomized male rats and adrenalectomized male rats which received corticosterone replacement. Three days after adrenalectomy, massive cell death, as detected by a dramatic increase in number of pyknotic cells, was observed in the granule cell layer of the dentate gyrus. By seven days following adrenalectomy, the numbers of pyknotic cells were even greater. Moreover, significant decreases in cross-sectional cell body area and numbers of dendritic branch points of Golgi-impregnated dentate gyrus granule cells were detected at seven days after adrenalectomy. Replacement of corticosterone to adrenalectomized rats prevented the appearance of large numbers of pyknotic cells as well as the decrease in granule cell cross-sectional cell body area and the numbers of dendritic branch points. In contrast, no obvious signs of degeneration were detected in the pyramidal cell layers of the CA1 and CA3 regions of the hippocampus at either three or seven days following adrenalectomy. In addition, no significant changes in morphological characteristics were observed in CA1 or CA3 pyramidal cells with adrenalectomy. These results show that dentate gyrus granule cells require glucocorticoids for their survival and for the maintenance of normal morphology and suggest that granule cell morphology and/or survival may undergo constant fluctuation in response to diurnal rhythms or stress-induced changes in glucocorticoid levels.
为了确定短期糖皮质激素处理是否会影响成年哺乳动物海马结构中神经元的形态和存活，我们对假手术雄性大鼠、肾上腺切除雄性大鼠以及接受皮质酮替代治疗的肾上腺切除雄性大鼠大脑中经高尔基染色和尼氏染色的组织进行了定量分析。肾上腺切除术后三天，在齿状回颗粒细胞层观察到大量细胞死亡，表现为固缩细胞数量急剧增加。肾上腺切除术后七天，固缩细胞数量更多。此外，肾上腺切除术后七天，经高尔基染色的齿状回颗粒细胞的细胞体横截面积和树突分支点数量显著减少。给肾上腺切除的大鼠补充皮质酮可防止大量固缩细胞的出现，以及颗粒细胞细胞体横截面积和树突分支点数量的减少。相比之下，肾上腺切除术后三天或七天，海马CA1和CA3区的锥体细胞层均未检测到明显的退变迹象。此外，肾上腺切除术后，CA1或CA3锥体细胞的形态特征未观察到显著变化。这些结果表明，齿状回颗粒细胞的存活和正常形态的维持需要糖皮质激素，并提示颗粒细胞的形态和/或存活可能会因昼夜节律或应激引起的糖皮质激素水平变化而不断波动。
