Farrar Matthew J, Rubin Jonathan D, Diago Darcy M, Schaffer Chris B
1] Department of Neurobiology and Behavior, Cornell University, Ithaca, New York, USA [2] Department of Biomedical Engineering, Cornell University, Ithaca, New York, USA.
1] Department of Biomedical Engineering, Cornell University, Ithaca, New York, USA [2] Department of Chemistry and Biochemistry, University of Colorado Boulder, Boulder, Colorado, USA.
J Cereb Blood Flow Metab. 2015 Mar 31;35(4):667-75. doi: 10.1038/jcbfm.2014.244.
The availability of transgenic strains has made the laboratory mouse a popular model for the study of healthy and diseased state spinal cord (SC). Essential to identifying physiologic and pathologic events is an understanding of the microvascular network and flow patterns of the SC. Using 2-photon excited fluorescence (2PEF) microscopy we performed in vivo measurements of blood flow in the lower thoracic portion of the mouse dorsal spinal vein (dSV) and in the first upstream branches supplying it, denoted as dorsal ascending venules (dAVs). We found that the dSV had large radiculomedullary veins (RMVs) exiting the SC, and that flow in the dSV between pairs of RMVs was bidirectional. Volumetric flow increased in each direction away from the point of bifurcation. Flow in the upstream dAVs varied with diameter in a manner consistent with a constant distal pressure source. By performing ex vivo 2PEF microscopy of fluorescent-gel perfused tissue, we created a 3-D map of the dorsal spinal vasculature. From these data, we constructed a simple model that predicted changes in the flow of upstream branches after occlusion of the dSV in different locations. Using an atraumatic model of dSV occlusion, we confirmed the predictions of this model in vivo.
转基因品系的可得性使实验室小鼠成为研究健康和患病状态脊髓（SC）的常用模型。了解脊髓的微血管网络和血流模式对于识别生理和病理事件至关重要。我们使用双光子激发荧光（2PEF）显微镜对小鼠背侧脊髓静脉（dSV）下胸段及其上游的第一分支（称为背侧升支小静脉，dAVs）的血流进行了体内测量。我们发现，dSV有大的根髓静脉（RMVs）穿出脊髓，并且在成对的RMVs之间的dSV中的血流是双向的。从分叉点向每个方向的体积流量都增加。上游dAVs中的血流随直径变化，其方式与恒定的远端压力源一致。通过对荧光凝胶灌注组织进行离体2PEF显微镜检查，我们创建了背侧脊髓脉管系统的三维图谱。根据这些数据，我们构建了一个简单模型，该模型预测了在不同位置阻塞dSV后上游分支血流的变化。使用dSV阻塞的无创模型，我们在体内证实了该模型的预测。
