Functional Morphology of Coronary Arteriol.es in Relation to Coronary Microcirculatory Disturbance by Micro-imaging Techniques

心脏收缩对心肌微血管的影响是冠状动脉微循环生理和病理生理调节的重要组成部分，并具有空间异质性。我们使用最先进的技术，包括日本同步辐射装置（Super Photon ring 8 GeV或Spring-8）的高度准直X射线束，常规X射线显微CT（μ CT）和共聚焦激光扫描显微镜（CLSM），研究了心动周期中完整心肌的三维（3-D）微血管结构。用St.托马斯停搏液灌注Langendorff灌流的大鼠心脏，以获得稳定的心脏停搏时间，用改良的Tyrode液灌注BaCl_2，以获得稳定的心脏收缩时间。使用微计算机断层扫描和共聚焦激光扫描显微镜对心肌中的微结构、毛细血管和微静脉的3-D成像在研究心动周期期间冠arteriol.es。与微动脉和微静脉相比，毛细血管对收缩期血管外压迫的抵抗力相对较强。一方面，微动脉和微静脉的阻力表现出较大的阶段性变化。线粒体NADI 1荧光成像评价局部缺氧的空间异质性及其与Langendorff灌注大鼠心脏微循环流量的相关性。心脏病和稳定的外观区域epimyocardiopathy dysocardiopathy状态显着相关的区域流量在微循环水平。

Effect of cardiac contraction on the myocardial microvessels form crucial part of the physiological and pathophysiological regulation of coronary microcirculation and is known to be spatially heterogeneous. We investigated the three-dimensional (3-D) microvascular architecture of intact myocardium during cardiac cycle using the state-of-the-art techniques including a highly collimated x-ray beam at the Japanese synchrotron radiation facility (Super Photon ring 8 GeV or Spring-8), conventional x-ray micro CT (μ CT), and confocal laser scanning microscopy (CLSM). Langendorff-perfused rat hearts were prepared for a stable diastole by perfusing St. Thomas cardioplegic solution and stable systole by modified Tyrode so lution with BaCl_2. The 3-D imaging of microstructures of the arteriol.es, capillaries, and venules in the myocardium using microcomputed tomography and con focal laser scanning microscopy were useful in inves tigating the coronary microvascular morphological and volumetric changes during cardiac cycle. Capillaries were relatively resistant to the systolic extravascular compression compared with arteriolar and venular microvessels. On one hand, arteriolar and venular microvessels showed a larger phasic change in resistance. The spatial heterogeneity of regional dysoxia and its correlation with microcirculatory flow in the Langendorff-perfused rat hearts was evaluated by mitochondria NADI1 fluorescent imaging. Hetero geneity and stable appearance of a regional epimyocardial dysoxic state were significantly related to regional flow at a microcirculatory level.