Kelly-Goss Molly R, Winterer Erica R, Stapor Peter C, Yang Ming, Sweat Richard S, Stallcup William B, Schmid-Schönbein Geert W, Murfee Walter L
Department of Biomedical Engineering, Tulane University, New Orleans, LA 70118, USA.
BMC Physiol. 2012 Jun 21;12:7. doi: 10.1186/1472-6793-12-7.
Observations in our laboratory provide evidence of vascular islands, defined as disconnected endothelial cell segments, in the adult microcirculation. The objective of this study was to determine if vascular islands are involved in angiogenesis during microvascular network growth.
Mesenteric tissues, which allow visualization of entire microvascular networks at a single cell level, were harvested from unstimulated adult male Wistar rats and Wistar rats 3 and 10 days post angiogenesis stimulation by mast cell degranulation with compound 48/80. Tissues were immunolabeled for PECAM and BRDU. Identification of vessel lumens via injection of FITC-dextran confirmed that endothelial cell segments were disconnected from nearby patent networks. Stimulated networks displayed increases in vascular area, length density, and capillary sprouting. On day 3, the percentage of islands with at least one BRDU-positive cell increased compared to the unstimulated level and was equal to the percentage of capillary sprouts with at least one BRDU-positive cell. At day 10, the number of vascular islands per vascular area dramatically decreased compared to unstimulated and day 3 levels.
These results show that vascular islands have the ability to proliferate and suggest that they are able to incorporate into the microcirculation during the initial stages of microvascular network growth.
我们实验室的观察结果表明，在成年微循环中存在血管岛，即定义为不相连的内皮细胞段。本研究的目的是确定血管岛在微血管网络生长过程中是否参与血管生成。
从未受刺激的成年雄性Wistar大鼠以及经化合物48/80诱导肥大细胞脱颗粒进行血管生成刺激后3天和10天的Wistar大鼠中获取肠系膜组织，这些组织能够在单细胞水平上观察整个微血管网络。对组织进行PECAM和BRDU免疫标记。通过注射FITC-葡聚糖鉴定血管腔，证实内皮细胞段与附近的开放网络断开连接。受刺激的网络显示血管面积、长度密度和毛细血管芽生增加。在第3天，至少有一个BRDU阳性细胞的岛的百分比与未受刺激水平相比增加，并且与至少有一个BRDU阳性细胞的毛细血管芽的百分比相等。在第10天，每血管面积的血管岛数量与未受刺激和第3天的水平相比显著减少。
这些结果表明血管岛具有增殖能力，并表明它们能够在微血管网络生长的初始阶段融入微循环。
