Repetitive episodes of brief ischaemia (12 min) do not produce a cumulative depletion of high energy phosphate compounds.
Repetitive episodes of brief ischaemia (12 min) do not produce a cumulative depletion of high energy phosphate compounds.
复制标题
重复发生短暂缺血（12 分钟）不会累积消耗高能磷酸盐化合物。
DOI：
10.1093/cvr/18.5.264
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发表时间：
1984
影响因子：
10.8
通讯作者：
Holmes,EW
中科院分区：
文献类型：
--
作者：
Swain,JL;Sabina,RL;Hines,JJ;GreenfieldJr,JC;Holmes,EW
在心肌缺血期间，心肌细胞的嘌呤（ATP，GTP）和嘧啶（CTP，UTP）核苷酸含量下降福尔斯。当缺血发作消退时，需要数小时甚至数天来恢复核苷酸库。这些观察结果表明，反复发作的缺血可能会产生渐进的耗尽的核苷酸池。为了确定短暂缺血重复发作对核苷酸库的影响，开胸犬进行了三次12分钟的左前降支冠状动脉闭塞，每次闭塞后再灌注10分钟。在第一次闭塞期间，核苷酸池减少了30%（ATP）、36%（GTP）、52%（CTP）和48%（UTP）。随后的两次封闭没有进一步减少核苷酸库。腺嘌呤核苷酸catenin（腺苷+肌苷+次黄嘌呤）的心肌含量在第一次闭塞期间往往大于随后的闭塞期间，并且底物输送（即局部心肌血流量）在每个缺血期间相似。这些结果表明，核苷酸降解速率的降低，而不是核苷酸合成的增加，解释了初始缺血期后随后的缺血发作期间核苷酸含量的维持。因此，局部缺血的反复发作不会导致心肌高能磷酸盐含量的累积降低。
During myocardial ischaemia the purine (ATP, GTP) and pyrimidine (CTP, UTP) nucleotide content of the myocyte falls. When the ischaemic episode resolves, many hours or even days are required for restoration of nucleotide pools. These obervations suggest that repetitive episodes of ischaemia might produce progressive depletion of nucleotide pools. In order to determine the effect of repetitive episodes of brief ischaemia on nucleotide pools, open-chest dogs underwent three 12 min periods of occlusion of the left anterior descending coronary artery, with each occlusion followed by 10 min of reperfusion. During the first occlusion nucleotide pools decreased by 30% (ATP); 36% (GTP), 52% (CTP), and 48% (UTP). The subsequent two occlusions produced no further decrease in nucleotide pools. The myocardial content of adenine nucleotide catabolites (adenosine + inosine + hypoxanthine) tended to be greater during the first occlusion than during the subsequent occlusions, and substrate delivery (ie regional myocardial blood flow) was similar during each of the periods of ischaemia. These results indicate that a decrease in the rate of nucleotide degradation, rather than an increase in nucleotide synthesis, accounts for the maintenance of nucleotide content during subsequent ischaemic episodes after the initial ischaemic period. Thus repetitive episodes of regional ischaemia do not produce a cumulative decrease in the high energy phosphate content of the myocardium.