Onset of aquaporin-4 expression in the developing mouse brain
Onset of aquaporin-4 expression in the developing mouse brain
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DOI：
10.1016/j.ijdevneu.2014.06.001
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发表时间：
2014-08-01
影响因子：
1.8
通讯作者：
Mack, Andreas F.
中科院分区：
文献类型：
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作者：
Fallier-Becker, Petra;Vollmer, Joerg P.;Mack, Andreas F.
水通道蛋白4(Aquaporin-4，AQP4)是大脑中主要的水通道，参与维持脑内内环境的稳定和水的交换。在成年哺乳动物的大脑中，它主要在星形胶质细胞中表达，在血管周围和软膜下终足膜中高密度表达。在这里，我们讨论了这种两极分化的表达是如何在发育过程中建立的问题。我们使用针对AQP4、闭锁带蛋白-1、胶质纤维酸性蛋白和β-营养不良蛋白的免疫细胞化学方法来跟踪E15到P3 NMRI小鼠脑内星形胶质细胞的发育和AQP4的表达。此外，我们还利用冷冻断裂电子显微镜在超微结构水平上检测到AQP4以颗粒正交表(OAP)的形式出现。我们分析了前脑切片的腹侧、外侧和背侧区域，发现AQP4免疫阳性反应出现在E16腹侧(E17)和背侧(E18)区域。AQP4染色遍及细胞突起，包括发育中的皮质区域的放射状胶质细胞，并在P1-P3时仅限于星形胶质细胞末端。用GFAP双标记法证实了这一点。在冷冻骨折的复制品中，发现OAP有轻微的时间延迟，但具有类似的腹侧到背侧的斜率。因此，AQP4在胚胎小鼠大脑中从EL 6开始表达，比之前报道的更早。然而，在出生前后的后期阶段，体内平衡功能和水分平衡所必需的两极分化表达出现。(C)2014年综合业务数字网。爱思唯尔有限公司出版。保留所有权利。
The main water channel in the brain, aquaporin-4 (AQP4) is involved in maintaining homeostasis and water exchange in the brain. In adult mammalian brains, it is expressed in astrocytes, mainly, and in high densities in the membranes of perivascular and subpial endfeet. Here, we addressed the question how this polarized expression is established during development. We used immunocytochemistly against AQP4, zonula occludens protein-1, glial fibrillary acidic protein, and beta-dystroglycan to follow astrocyte development in E15 to P3 NMRI mouse brains, and expression of AQP4. In addition we used freeze-fracture electron microscopy to detect AQP4 in the form of orthogonal arrays of particles (OAPs) on the ultrastructural level.We analyzed ventral, lateral, and dorsal regions in forebrain sections and found AQP4 immunoreactivity to emerge at E16 ventrally before lateral (E17) and dorsal (E18) areas. AQP4 staining was spread over cell processes including radial glial cells in developing cortical areas and became restricted to astroglial endfeet at P1-P3. This was confirmed by double labeling with GFAP. In freeze-fracture replicas OAPs were found with a slight time delay but with a similar ventral to dorsal gradient. Thus, AQP4 is expressed in the embryonic mouse brain starting at El 6, earlier than previously reported. However a polarized expression necessary for homeostatic function and water balance emerges at later stages around and after birth. (C) 2014 ISDN. Published by Elsevier Ltd. All rights reserved.