Koning M M, Simonis L A, de Zeeuw S, Nieukoop S, Post S, Verdouw P D
Thoraxcenter, Erasmus University Rotterdam, The Netherlands.
Cardiovasc Res. 1994 Aug;28(8):1146-51. doi: 10.1093/cvr/28.8.1146.
The aim was to investigate whether ischaemic preconditioning can be obtained by a partial coronary artery occlusion without intermittent reperfusion.
In seven anaesthetised open chest pigs, the flow in the proximal left anterior descending coronary artery was reduced to 30% of baseline during 30 min before the vessel was occluded completely for 60 min (60 min total coronary occlusion, TCO). After 2 h of reperfusion, the area at risk (AR) and infarct size (IS) were determined using standard procedures. Infarct sizes were compared to those observed in control animals (n = 12), which were subjected to 60 min TCO and 2 h reperfusion, and to infarct sizes determined in animals preconditioned by 10 min TCO with either 15 min (n = 10) or 60 min (n = 5) of reperfusion before the 60 min TCO and 2 h reperfusion. In the last three groups of animals, area at risk was varied by occluding the coronary artery or its branches at different sites.
In the control animals infarct size was linearly related (r = 0.99, p < 0.001) to the area at risk with a positive intercept on the AR axis: IS/LVmass (x100%) = 0.88 AR/LVmass (x100%)-3.6. At comparable areas at risk, the infarct size of the animals preconditioned with a 10 min TCO was less than for the control animals. For the animals preconditioned with 10 min TCO and 15 min reperfusion, the relationship between infarct size and area at risk was again linear (r = 0.88) and also had a positive intercept on the AR axis: IS/LVmass (x100%) = 0.68 AR/LVmass (x100%)-4.8. All animals with the flow reduction to 30% of baseline immediately preceding the 60 min TCO had infarct sizes smaller (p < 0.05) than predicted from the regression equation for the control animals, but the infarct size limitation could not be simply related to variables such as changes in regional systolic and postsystolic segment length shortening, ATP, or ADP during the partial occlusion period.
Myocardium can be preconditioned with a flow reduction to 30% of baseline for 30 min without intermittent reperfusion (two stage Harris model). The positive intercept on the AR axis of the IS-AR relationship warrants caution of the use of IS/AR as an index for infarct size limitation.
研究是否可通过部分冠状动脉闭塞而无间歇性再灌注来实现缺血预处理。
在7只麻醉开胸猪中，在完全闭塞左前降支冠状动脉60分钟（总冠状动脉闭塞60分钟，TCO）前30分钟，将左前降支冠状动脉近端血流降至基线的30%。再灌注2小时后，采用标准程序测定危险区（AR）和梗死面积（IS）。将梗死面积与对照组动物（n = 12）进行比较，对照组动物接受60分钟TCO和2小时再灌注，并与在60分钟TCO和2小时再灌注前经10分钟TCO预处理、再灌注15分钟（n = 10）或60分钟（n = 5）的动物所测定的梗死面积进行比较。在最后三组动物中，通过在不同部位闭塞冠状动脉或其分支来改变危险区。
在对照组动物中，梗死面积与危险区呈线性相关（r = 0.99，p < 0.001），在AR轴上有正截距：IS/LV质量（×100%）= 0.88 AR/LV质量（×100%） - 3.6。在可比的危险区，经10分钟TCO预处理的动物梗死面积小于对照组动物。对于经10分钟TCO和15分钟再灌注预处理的动物，梗死面积与危险区之间的关系再次呈线性（r = 0.88），在AR轴上也有正截距：IS/LV质量（×100%）= 0.68 AR/LV质量（×100%） - 4.8。所有在60分钟TCO前立即将血流降至基线30%的动物，其梗死面积均小于（p < 0.05）根据对照组动物回归方程预测的值，但梗死面积的限制不能简单地与部分闭塞期间区域收缩期和收缩后期节段长度缩短、ATP或ADP的变化等变量相关。
可在无间歇性再灌注的情况下，将血流降至基线的30%持续30分钟对心肌进行预处理（两阶段哈里斯模型）。IS - AR关系在AR轴上的正截距提示在使用IS/AR作为梗死面积限制指标时应谨慎。
