Reitsma Sietze, oude Egbrink Mirjam G A, Vink Hans, van den Berg Bernard M, Passos Valéria Lima, Engels Wim, Slaaf Dick W, van Zandvoort Marc A M J
Department of Biomedical Engineering, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands.
J Vasc Res. 2011;48(4):297-306. doi: 10.1159/000322176. Epub 2011 Jan 27.
The endothelial glycocalyx (EG) is the carbohydrate-rich luminal lining of endothelial cells that mediates permeability and blood cell-vessel wall interactions. To establish an atheroprotective role of the EG, adequate imaging and quantification of its properties in intact, viable, atherogenesis-prone arteries is needed.
Carotid arteries of C57Bl6/J mice (n=22) were isolated including the bifurcation, mounted in a perfusion chamber, and perfused with fluorescent lectin wheat germ agglutinin-fluorescein isothiocyanate. The EG was visualized through the vessel wall using two-photon laser scanning microscopy. An image quantification protocol was developed to assess EG thickness, which was sensitive to hyaluronidase-induced changes.
In the lesion-protected common carotid artery, EG thickness was found to be 2.3 ± 0.1 μm (mean ± SEM), while the surface area devoid of (wheat germ agglutinin-sensitive) EG was 8.9 ± 4.2%. Data from the external carotid artery were similar (2.5 ± 0.1 μm; 9.1 ± 5.0%). In the atherogenesis-prone internal carotid artery the EG-devoid surface area was significantly higher (27.4 ± 5.5%, p<0.05); thickness at the remaining areas was 2.5 ± 0.1 μm.
The EG can be adequately imaged and quantified using two-photon laser scanning microscopy in intact, viable mounted carotid arteries. Spatial EG differences could underlie atherogenesis.
内皮糖萼（EG）是内皮细胞富含碳水化合物的管腔内膜，介导通透性和血细胞与血管壁的相互作用。为确定EG的抗动脉粥样硬化作用，需要在完整、有活力、易发生动脉粥样硬化的动脉中对其特性进行充分成像和定量分析。
分离22只C57Bl6/J小鼠的颈动脉（包括分叉处），安装在灌注室中，并用荧光凝集素异硫氰酸荧光素标记的麦胚凝集素进行灌注。使用双光子激光扫描显微镜透过血管壁观察EG。开发了一种图像定量方案来评估EG厚度，该方案对透明质酸酶诱导的变化敏感。
在病变保护的颈总动脉中，EG厚度为2.3±0.1μm（平均值±标准误），而无（对麦胚凝集素敏感的）EG的表面积为8.9±4.2%。来自颈外动脉的数据相似（2.5±0.1μm；9.1±5.0%）。在易发生动脉粥样硬化的颈内动脉中，无EG的表面积显著更高（27.4±5.5%，p<0.05）；其余区域的厚度为2.5±0.1μm。
使用双光子激光扫描显微镜可以在完整、有活力的安装颈动脉中对EG进行充分成像和定量分析。EG的空间差异可能是动脉粥样硬化的基础。
