Cornford E M, Hyman S, Swartz B E
Department of Neurology, UCLA School of Medicine.
J Cereb Blood Flow Metab. 1994 Jan;14(1):106-12. doi: 10.1038/jcbfm.1994.15.
Immunogold electron microscopy was used to examine human brain resections to localize the GLUT1 glucose transporter. The tissue examined was obtained from a patient undergoing surgery for treatment of seizures, and the capillary profiles examined had characteristics identical to those described previously for active, epileptogenic sites (confirmed by EEG analyses). A rabbit polyclonal antiserum to the full-length human erythrocyte glucose transporter (GLUT1) was labeled with 10-nm gold particle-secondary antibody conjugates and localized immunoreactive GLUT1 molecules in human brain capillary endothelia, with < 0.25% of the particles beyond the capillary profile. Erythrocyte membranes were also highly immunoreactive, whereas macrophage membranes were GLUT1-negative. The number of immunoreactive sites per capillary profile was observed to be 10-fold greater in humans than in previous studies of rat and rabbit brain capillaries. In addition, half of the total number of immunoreactive gold particles were localized to the luminal capillary membrane. We suggest that the blood-brain barrier GLUT1 glucose transporter is up-regulated in seizures, and this elevated transporter activity is characterized by increased GLUT1 transporters, particularly on the luminal capillary membranes. In addition, acute modulation of glucose transporter activity is presumed to involve translocation of GLUT1 from cytoplasmic to luminal membrane sites, demonstrable with quantitative immunogold electron microscopy.
免疫金电子显微镜技术被用于检查人类脑切除组织，以定位葡萄糖转运蛋白1（GLUT1）。所检查的组织取自一名接受癫痫治疗手术的患者，所检查的毛细血管轮廓具有与先前描述的活跃致痫部位相同的特征（经脑电图分析证实）。用10纳米金颗粒-二抗偶联物标记针对全长人类红细胞葡萄糖转运蛋白（GLUT1）的兔多克隆抗血清，并在人脑毛细血管内皮中定位免疫反应性GLUT1分子，超过毛细血管轮廓的颗粒不到0.25%。红细胞膜也具有高度免疫反应性，而巨噬细胞膜GLUT1呈阴性。观察到，与先前对大鼠和兔脑毛细血管的研究相比，人类每个毛细血管轮廓上免疫反应位点的数量多10倍。此外，免疫反应性金颗粒总数的一半定位于毛细血管腔膜。我们认为，血脑屏障GLUT1葡萄糖转运蛋白在癫痫发作时上调，这种转运蛋白活性的升高表现为GLUT1转运蛋白增加，尤其是在毛细血管腔膜上。此外，推测葡萄糖转运蛋白活性的急性调节涉及GLUT1从细胞质膜向腔膜位点的转运，这可以通过定量免疫金电子显微镜技术证实。
