心肌微循环改变在缺血再灌注损伤中作用的探讨

The Changes of Myocardial Microcirculation in Rabbit After Myocardial Ischemia and Reperfusion

目的探讨缺血与再灌注时心肌组织微循环的改变。方法采用家兔心肌缺血与再灌注模型 ,观察心肌组织毛细血管腔内和管壁的变化以及心肌细胞与间质的形态学改变 ,并测定血浆神经肽Y和内皮素水平及心肌组织微动脉、微静脉和毛细血管截面积。结果与对照组比较 ,实验组心肌组织毛细血管显著扩张 (P<0.001) ,微动脉、微静脉显著收缩(P<0.05),实验组心肌缺血时血浆神经肽Y和内皮素水平显著上升(P<0.001) ,再灌注时进一步上升 (P<0.001)。心肌组织毛细血管内皮细胞脱落、固缩、变性和坏死 ,管腔内血细胞排列成串 ,心肌细胞水肿、变性、坏死 ,肌浆溶解 ,心内膜和心外膜下心肌间质广泛出血 ,心肌间质中性粒细胞呈小片状浸润 ,部分形成微脓肿。结论心肌组织微循环的改变在缺血再灌注损伤的发生机制中可能占重要地位。

Objective To sdudy the changes of myocardial microcirculation in rabbit after myocardial is-chemia and reperfusion.Methods Myocardial ischemia reperfusion rabbit modes were established.Cardiac mi-croartery、microvein and capillary section areas were determined.Plasma neuropeptide Y and endothelin levels were measured.The changes of cardiocyte,interstitium and the cavity together with the wall of cardiac capillary were ob-served with light microscope.Results Cardiac capillary section area in the experiment group was significantly larg-er than that of the controls,whereas the section area of microartery and microvein was smaller than that of the con-trols.Plasma neuropeptide Y and endothelin levels significantly rose after myocardial ischemia and reperfusion.Compared with the control group,desquamation、pyknosis、degeneration and necrosis of cardiac capillary endothelio-cyte were observed in the experiment group.Blood cells in cardiac capillary vessel cavity of the experiment group ranged in bunch.Subendocardial and subepicardial interstitium hemorrhage、neutrophilic leukocyte soakage in my-ocardial interstitium with local microabscess、sarcoplasm liquefaction and myocardial edema、degeneration and necrosis can also be observed in the experiment group.Conclusions The changes of myocardial microcirculation may play an important role in the pathogenesis of myocardial ischemia reperfusion injury.