血管周围空间(PVS)围绕脑血管,在清除大脑中的废物中起着重要作用。他们的解剖结构和功能已经被描述为动脉,但是静脉周围的PVS特征仍然很差。在小鼠体内使用2光子成像,我们确定了动脉和静脉周围PVS的大小,以及它们与蛛网膜下腔的联系.通过大脑池将70kDFITC-葡聚糖注入脑脊液后,标记的PVS在动脉周围很明显,但是静脉显示PVS的标记频率较低。PVS的大小与毛细血管动脉和静脉的血管大小相关,但不是用于穿透血管。脑膜动脉和静脉周围的PVS被薄薄的脑膜层与蛛网膜下腔隔开,这并没有形成示踪剂的屏障。在体内,在血管壁附近观察到FITC-葡聚糖信号,但最低限度的墙本身。验尸后,示踪剂在动脉壁内的位置有明显的变化,延伸到平滑肌层。一起来看,这些发现表明静脉周围的PVS在CSF和脑实质之间的溶质交换中的作用有限。
The perivascular space (PVS) surrounds cerebral blood vessels and plays an important role in clearing waste products from the brain. Their anatomy and function have been described for arteries, but PVS around
veins remain poorly characterized. Using in vivo 2-photon imaging in mice, we determined the size of the PVS around arteries and
veins, and their connection with the subarachnoid space. After infusion of 70 kD FITC-dextran into the cerebrospinal fluid via the cisterna magna, labeled PVS were evident around arteries, but
veins showed less frequent labeling of the PVS. The size of the PVS correlated with blood vessel size for both pial arteries and veins, but not for penetrating vessels. The PVS around pial arteries and
veins was separated from the subarachnoid space by a thin meningeal layer, which did not form a barrier for the tracer. In vivo, FITC-dextran signal was observed adjacent to the vessel wall, but minimally within the wall itself. Post-mortem, there was a significant shift in the tracer\'s location within the arterial wall, extending into the smooth muscle layer. Taken together, these findings suggest that the PVS around
veins has a limited role in the exchange of solutes between CSF and brain parenchyma.