Rodriguez-Baeza A, Reina-De La Torre F, Ortega-Sanchez M, Sahuquillo-Barris J
Department of Morphological Sciences, Faculty of Medicine, Autonomous University of Barcelona, Spain.
Anat Rec. 1998 Oct;252(2):176-84. doi: 10.1002/(SICI)1097-0185(199810)252:2<176::AID-AR3>3.0.CO;2-1.
Scanning electron microscopy (SEM) of microvascular corrosion casts revealed perivascular structures that resembled smooth muscle and pericyte cells. Although these structures have been studied in widely different experimental contexts, their origin, function, and distribution pattern in different tissues are not understood. Microvascular corrosion casts from 15 fresh human brains and 20 lumbar spinal cords were studied by SEM. In five cerebral hemispheres a fluorescent resin was injected in order to study the vascular bed by confocal laser scanning microscopy (CLSM). Microvascular casts showed two perivascular structures on their surfaces: plastic strips, which formed a muff around arteriolar vessels, and pericyte-like structures that were present around the capillary network. Their morphological characteristics and distribution were similar to those of smooth muscle cells and pericytes, respectively. The SEM study showed that these structures were not tightly joined to the cast surface, but were connected to the vascular cast by narrow plastic connections. The CLSM showed that the resin invaded the subendothelial space, thus giving rise to these structures. Perivascular structures associated with arteriolar and capillary vessels appear to represent smooth muscle cells and pericytes. They are formed by the passage of the resin to the subendothelial space, probably through weak endothelial cell junctions. The effusion of resin into the subendothelial space may represent evidence for the structural basis of myocyte and pericyte cell control. Chemical communication by substances released locally or transported to these cells through these junctions may regulate their functions, allowing them to regulate blood flow.
微血管铸型的扫描电子显微镜（SEM）检查发现了类似平滑肌细胞和周细胞的血管周围结构。尽管这些结构已在广泛不同的实验环境中进行了研究，但其在不同组织中的起源、功能和分布模式仍不清楚。通过SEM对15个新鲜人脑和20个腰段脊髓的微血管铸型进行了研究。在五个大脑半球中注入了荧光树脂，以便通过共聚焦激光扫描显微镜（CLSM）研究血管床。微血管铸型在其表面显示出两种血管周围结构：形成围绕小动脉血管的套筒的塑料条，以及存在于毛细血管网络周围的类周细胞结构。它们的形态特征和分布分别与平滑肌细胞和周细胞相似。SEM研究表明，这些结构并未紧密连接到铸型表面，而是通过狭窄的塑料连接与血管铸型相连。CLSM显示树脂侵入了内皮下间隙，从而产生了这些结构。与小动脉和毛细血管相关的血管周围结构似乎代表平滑肌细胞和周细胞。它们是由树脂进入内皮下间隙形成的，可能是通过薄弱的内皮细胞连接。树脂渗入内皮下间隙可能代表了心肌细胞和周细胞控制的结构基础的证据。通过局部释放或通过这些连接运输到这些细胞的物质进行化学通讯可能调节它们的功能，使它们能够调节血流。
