Hypervascularization in the magnocellular nuclei of the rat hypothalamus: Relationship with the distribution of aquaporin-4 and markers of energy metabolism
Hypervascularization in the magnocellular nuclei of the rat hypothalamus: Relationship with the distribution of aquaporin-4 and markers of energy metabolism
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DOI：
10.1046/j.1365-2826.2000.00539.x
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发表时间：
2000-10-01
影响因子：
3.2
通讯作者：
Lasbennes, F
中科院分区：
文献类型：
--
作者：
Badaut, J;Nehlig, A;Lasbennes, F
在下丘脑的大细胞核中，有一个丰富的血管网络，其功能仍有待建立。在视上核中，高血管密度可能是一个元素，它与星形胶质细胞中表达的水通道水通道蛋白-4一起，与神经元受体的作用有关。我们通过研究室旁核和视上核中血管和细胞密度之间的相关性来验证神经元接受假说。水通道蛋白-4是否可能有助于通过研究在下丘脑的大细胞核中的分布来测试接收。高血管密度也可能反映了由于加压素和催产素的合成而引起的高代谢活性。通过研究区域细胞色素氧化酶组织化学、局部脑血流量和视上核和室旁核中葡萄糖转运蛋白1的密度，验证了这一代谢假说。所有的大细胞核的特点是广泛和强烈的水通道蛋白-4标记和弱细胞色素氧化酶组织化学。视上核和室旁核大细胞区血管密度最高。与大脑皮质相比，室旁核和视上核的局部脑血流量出奇地低。此外，在这些细胞核中，葡萄糖转运蛋白1型的抗体揭示了两个群体的血管不同的标记强度。不同的核团之间观察到的相似性表明，在下丘脑，所有的大细胞区域的感觉血浆渗透压。低局部脑血流量，葡萄糖转运蛋白1型标记和细胞色素氧化酶组织化学的模式表明，这些下丘脑核团的高血管化是不相关的基础条件下的高代谢能力。
In the magnocellular nuclei of the hypothalamus, there is a rich vascular network for which the function remains to be established. In the supraoptic nucleus, the high vascular density may be one element, which together with the water channel aquaporin-4 expressed in the astrocytes, is related to a role in osmoreception. We tested the osmoreception hypothesis by studying the correlation between vascular and cellular densities in the paraventricular nucleus and the supraoptic nucleus. Whether aquaporin-4 is likely to contribute to osmoreception was tested by studying the distribution in the magnocellular nuclei of the hypothalamus. The high vascular density may also reflect a high metabolic activity due to the synthesis of vasopressin and oxytocin. This metabolic hypothesis was tested by studying the regional cytochrome oxidase histochemistry, the local cerebral blood flow, and the density of glucose transporter type-1 in the supraoptic and paraventricular nuclei. All the magnocellular nuclei were characterized by an extended and intense aquaporin-4 labelling and a weak cytochrome oxidase histochemistry. The highest vascular density was found in the supraoptic nucleus and the magnocellular regions of the paraventricular nucleus. The local cerebral blood flow rates were surprisingly low in the paraventricular nucleus and the supraoptic nucleus in comparison to the cerebral cortex. Furthermore in these nuclei, the antibody for glucose transporter type-1 revealed two populations of vessels differing by their labelling intensity. The similarities observed between the different nuclei suggest that, in the hypothalamus, all magnocellular regions sense the plasma osmolarity. The low local cerebral blood flow, and the patterns of glucose transporter type-1 labelling and cytochrome oxidase histochemistry suggest that the high vascularization of these hypothalamic nuclei is not related to a high metabolic capacity in basal conditions.