Cellular and subcellular evidence for neuronal interaction between the chemokine stromal cell-derived factor-1/CXCL 12 and vasopressin: Regulation in the hypothalamo-neurohypophysial system of the Brattleboro rats
Cellular and subcellular evidence for neuronal interaction between the chemokine stromal cell-derived factor-1/CXCL 12 and vasopressin: Regulation in the hypothalamo-neurohypophysial system of the Brattleboro rats
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DOI：
10.1210/en.2007-1097
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发表时间：
2008-01-01
期刊：
影响因子：
4.8
通讯作者：
Rostene, William
中科院分区：
文献类型：
--
作者：
Callewaere, Celine;Fernette, Brigitte;Rostene, William
我们先前描述了精氨酸加压素(AVP)和趋化因子基质细胞衍生因子-1α(SDF-1)在下丘脑视上核、室旁核和垂体后叶的大细胞神经元中的共存。SDF-1在生理上影响AVP神经元的电生理特性，从而影响AVP的释放。在本研究中，我们用共聚焦显微镜和电子显微镜证实，AVP和SDF-1在神经细胞内有相似的细胞分布，并可在垂体后叶神经末梢的致密核心小泡中找到。由于Brattleboro大鼠代表了AVP缺乏的良好模型，我们在这些动物身上测试了SDF-1及其受体CXCR4的命运。免疫组织化学染色证实SDF-1和CXCR4在Brattleboro大鼠脑内的表达均显著降低，并与视上核、室旁核和垂体后叶AVP蛋白的表达密切相关。我们通过实时定量聚合酶链式反应观察到SDF-1mRNA在杂合子和纯合子大鼠中的表达增加。对SDF-1/CXCR4系统的影响与外周肾脏水平衡的改变无关，因为它不能通过长期输注AVP V2受体激动剂去氨基-8D-精氨酸加压素来恢复。这些原始数据进一步表明，SDF-1可能在水平衡的调节中发挥重要作用。
We previously described a colocalization between arginine vasopressin (AVP) and the chemokine stromal cell-derived factor-1 alpha (SDF-1) in the magnocellular neurons of both the hypothalamic supraoptic and paraventricular nucleus as well as the posterior pituitary. SDF-1 physiologically affects the electrophysiological properties of AVP neurons and consequently AVP release. In the present study, we confirm by confocaland electron microscopy that AVP and SDF-1 have a similar cellular distribution inside the neuronal cell and can be found in dense core vesicles in the nerve terminals in the posterior pituitary. Because the Brattleboro rats represent a good model of AVP deficiency, we tested in these animals the fate of SDF-1 and its receptor CXCR4. We identified by immunohistochemistry that both SDF-1 and CXCR4 immunoreactivity were strongly decreased in Brattleboro rats and were strictly correlated with the expression of AVP protein in supraoptic nucleus, paraventricular nucleus, and the posterior pituitary. We observed by real-time PCR an increase in SDF-1 mRNA in both heterozygous and homozygous rats. The effect on the SDF-1/CXCR4 system was not linked to peripheral modifications of kidney water balance because it could not be restored by chronic infusion of deamino-8D-ariginine-vasopressin, an AVP V2-receptor agonist. These original data further suggest that SDF-1 may play an essential role in the regulation of water balance.