Hypoxic preconditioning of ischaemic canine myocardium.
Hypoxic preconditioning of ischaemic canine myocardium.
复制标题
DOI：
10.1093/cvr/26.5.534
复制
发表时间：
1992-05
影响因子：
10.8
通讯作者：
Y. Shizukuda;R. Mallet;Shang-Chiun Lee;Downey Hf
中科院分区：
文献类型：
--
作者：
Y. Shizukuda;R. Mallet;Shang-Chiun Lee;Downey Hf
目的：探讨短期非缺血性缺氧对心肌的预适应作用。方法成年杂种犬60只，雌雄不限，行冠状动脉左前降支阻断60 min，再灌注5 h。在治疗组中，心脏预处理5分钟的冠状动脉灌注缺氧血[O2含量9.2（SEM 0.6）毫升升-1]或5分钟闭塞，然后再灌注10分钟，60分钟闭塞。评估这些治疗对心肌梗死面积和局部收缩功能的影响。结果：缺氧预处理心脏的心肌梗死面积占危险解剖面积的百分比显著降低，为7.2（1.8）%，对照组为22.4（4.6）%（p < 0.01），但与缺血预处理心脏无差异[4.6（1.7）%; p < 0.01 v control]。危险解剖面积（以左心室质量的百分比表示）和缺血壁内三分之二的侧支血流在各组之间没有差异。缺血预处理抑制局部收缩功能，但低氧预处理不抑制。在再灌注60分钟闭塞，明显的矛盾收缩期延长是明显的缺血预处理和对照组的心脏，但不是在缺氧预处理心肌。结论：缺氧预处理和缺血预处理5分钟对心肌梗死的预防作用相同，而缺血预处理对缺血后心肌收缩功能的影响更大。
OBJECTIVE The aim was to test whether a brief period of non-ischaemic hypoxia can precondition myocardium. METHODS 60 anaesthetised adult mongrel dogs of either sex underwent 60 min occlusion of the left anterior descending coronary artery, followed by 5 h reperfusion. In treated groups, hearts were either preconditioned with 5 min coronary perfusion with hypoxic blood [O2 content 9.2(SEM 0.6) ml.litre-1] or 5 min occlusion followed by a 10 min reperfusion period prior to 60 min occlusion. The effect of these treatments on myocardial infarct size and regional contractile function was assessed. RESULTS Infarct size, determined by tetrazolium staining, as a percentage of anatomical area at risk was markedly decreased in hypoxia preconditioned hearts, at 7.2(1.8)% v 22.4(4.6)% in controls (p < 0.01), but did not differ from ischaemia preconditioned hearts [4.6(1.7)%; p < 0.01 v control]. Anatomical area at risk, expressed as a percentage of left ventricular mass, and collateral blood flow to the inner two thirds of the ischaemic wall did not differ among the groups. Regional contractile function was depressed following ischaemic preconditioning but not following hypoxic preconditioning. During reperfusion following 60 min occlusion, marked paradoxical systolic lengthening was evident in ischaemia preconditioned and control hearts but not in hypoxia preconditioned myocardium. CONCLUSIONS Five minutes of hypoxic and ischaemic preconditioning were equipotent in preventing infarction, whereas ischaemic preconditioning caused a greater decrement in postischaemic contractile function.