Chronic corticosterone affects brain weight, and mitochondrial, but not glial volume fraction in hippocampal area CA3
Chronic corticosterone affects brain weight, and mitochondrial, but not glial volume fraction in hippocampal area CA3
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DOI：
10.1016/j.neuroscience.2003.11.031
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发表时间：
2004-01-01
期刊：
影响因子：
3.3
通讯作者：
Anderson, BJ
中科院分区：
文献类型：
--
作者：
Coburn-Litvak, PS;Tata, DA;Anderson, BJ
皮质酮（Corticosterone，CORT）是啮齿类动物体内最主要的糖皮质激素，对海马CA 3区有损伤作用。在这里，我们研究如何在细胞和超微结构水平的分析，损害表示。大鼠皮下注射CORT（26.8 mg/kg，s.c.）汽车56天用物理计数器法估计细胞计数。从电子显微照片中获得神经胶质和线粒体的体积分数。使用CORT剂量的有效性通过两种方式证明。首先，CORT显著抑制体重增加相对于车辆。第二，CORT显著降低肾上腺、心脏和腓肠肌重量。肾上腺和腓肠肌重量与体重的比值也显著降低。尽管绝对脑重量降低，但CORT组的脑体重比高于溶媒组，表明大脑比许多外周器官和肌肉更能抵抗CORT的作用。与这种解释一致，CORT没有改变CA 3细胞密度，细胞层体积或顶端树突状神经元体积。同样，CORT没有显着改变胶质细胞的体积分数，但减少线粒体的体积分数。这些发现强调了需要超微结构分析，除了细胞水平的分析之前，可以得出结论，长期CORT升高的破坏性影响。线粒体的相对减少可能表明生物能量能力的降低，这反过来可能使CA 3易受代谢挑战的影响。(C)2004年IBRO。由爱思唯尔有限公司出版。保留所有权利。
Corticosterone (CORT), the predominant glucocorticoid in rodents, is known to damage hippocampal area CA3. Here we investigate how that damage is represented at the cellular and ultrastructural level of analyses. Rats were injected with CORT (26.8 mg/kg, s.c.) or vehicle for 56 days. Cell counts were estimated with the physical disector method. Glial and mitochondrial volume fractions were obtained from electron micrographs. The effectiveness of the CORT dose used was demonstrated in two ways. First, CORT significantly inhibited body weight gain relative to vehicles. Second, CORT significantly reduced adrenal gland, heart and gastrocnemius muscle weight. Both the adrenal and gastrocnemius muscle weight to body weight ratios were also significantly reduced. Although absolute brain weight was reduced, the brain to body weight ratio was higher in the CORT group relative to vehicles, suggesting that the brain is more resistant to the effects of CORT than many peripheral organs and muscles. Consistent with that interpretation, CORT did not alter CA3 cell density, cell layer volume, or apical dendritic neuropil volume. Likewise, CORT did not significantly alter glial volume fraction, but did reduce mitochondrial volume fraction. These findings highlight the need for ultrastructural analyses in addition to cellular level analyses before conclusions can be drawn about the damaging effects of prolonged CORT elevations. The relative reduction in mitochondria may indicate a reduction in bioenergetic capacity that, in turn, could render CA3 vulnerable to metabolic challenges. (C) 2004 IBRO. Published by Elsevier Ltd. All rights reserved.