Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama, USA.
J Histochem Cytochem. 2010 Jan;58(1):53-60. doi: 10.1369/jhc.2009.954610. Epub 2009 Sep 28.
Angiopoietin-1 (Angpt1; previously Ang-1) participates in vascular maintenance and remodeling. In the current study, we investigated the distribution of Angpt1 protein in rat brain. We detected Angpt1 immunoreactivity (IR) in cerebral blood vessels, cuboidal ependyma, and tanycytes, which are specialized hypothalamic bipolar ependymal cells. We also evaluated patterns of IR of endothelium-specific receptor tyrosine kinase 2 (Tie2, the receptor for Angpt1). Tie2 IR was present in Angpt1-immunoreactive cuboidal ependyma in a membranous pattern, suggesting an autocrine or paracrine role for Angpt1-Tie2. Tie2 IR was also associated with peri-ependymal blood vessels, some of which were contacted by tips of Angpt1-immunoreactive tanycyte processes, implying a potential functional ligand-receptor interaction mediating communication between the cerebrospinal fluid and vascular compartments. Because we previously found that cerebral Angpt1 expression was modulated by 17beta-estradiol (E2), and because some tanycyte functions are modulated by E2, we tested the hypothesis that E2 affects ependymal and tanycyte Angpt1 expression in vivo. No gross E2 effect on the ependymal pattern of Angpt1 IR or cerebral Angpt1 protein content was observed.
血管生成素 1（Angpt1；以前称为 Ang-1）参与血管的维持和重塑。在本研究中，我们研究了 Angpt1 蛋白在大鼠脑内的分布。我们在脑内血管、立方脑室内皮和室管膜下细胞（下丘脑特殊的双极室管膜细胞）中检测到 Angpt1 免疫反应性（IR）。我们还评估了内皮细胞特异性受体酪氨酸激酶 2（Tie2，Angpt1 的受体）的 IR 模式。Tie2 IR 以膜状模式存在于 Angpt1 免疫反应性的立方脑室内皮中，表明 Angpt1-Tie2 具有自分泌或旁分泌作用。Tie2 IR 还与室管膜周围血管相关，其中一些血管与 Angpt1 免疫反应性的室管膜下细胞突起的末端接触，暗示着一种潜在的功能性配体-受体相互作用，介导了脑脊液和血管腔之间的通讯。因为我们之前发现脑内 Angpt1 的表达受 17β-雌二醇（E2）调节，并且一些室管膜下细胞的功能受 E2 调节，所以我们测试了 E2 是否会影响体内室管膜和室管膜下细胞 Angpt1 的表达的假设。未观察到 E2 对 Angpt1 IR 或脑内 Angpt1 蛋白含量的室管膜模式有明显影响。
