Ince C, Ashruf J F, Avontuur J A, Wieringa P A, Spaan J A, Bruining H A
Department of Surgery, Erasmus University of Rotterdam, The Netherlands.
Am J Physiol. 1993 Feb;264(2 Pt 2):H294-301. doi: 10.1152/ajpheart.1993.264.2.H294.
Heterogeneity in the hypoxic state of Tyrode-perfused rat hearts was studied using NADH and Pd-porphine videofluorometry. Ischemic as well as high-flow anoxia resulted in a homogeneous rise of tissue NADH fluorescence, whereas normoxic recovery from both types of anoxia caused transiently persisting patchy fluorescent areas. Patterns were always the same for a given heart. PO2 distribution in the vasculature measured by Pd-porphine phosphorescence showed patterns similar to the NADH fluorescence patterns. Microsphere embolization of the capillaries, but not of arterioles, elicited identical NADH fluorescence patterns as seen during recovery from anoxia without microspheres. High heartbeat rates also caused patchy fluorescent areas but not in the presence of adenosine. Patterns corresponded to those seen during normoxic recovery from anoxia under low beat rates. It is concluded that there are circulatory units in the rat heart at the capillary level that result in the temporary persistence of anoxic areas during recovery from anoxia. These vulnerable areas are the first to be compromised during high heartbeat rates.
使用NADH和钯卟啉视频荧光测定法研究了泰罗德溶液灌注的大鼠心脏缺氧状态的异质性。缺血以及高流量缺氧导致组织NADH荧光均匀升高，而从这两种缺氧状态恢复至常氧时，会导致短暂持续的斑片状荧光区域。对于给定的心脏，模式总是相同的。通过钯卟啉磷光测量的血管系统中的PO2分布显示出与NADH荧光模式相似的模式。毛细血管而非小动脉的微球栓塞引发的NADH荧光模式与无微球时缺氧恢复期间所见的相同。高心率也会导致斑片状荧光区域，但在有腺苷存在的情况下不会出现。这些模式与低心率下从缺氧恢复至常氧期间所见的模式一致。结论是，大鼠心脏在毛细血管水平存在循环单元，这导致在从缺氧恢复过程中缺氧区域暂时持续存在。这些易损区域在高心率期间最先受到损害。
