大鼠心肌缺血再灌注模型中低温处理对心肌无复流的影响分析

摘要 目的：探究低温治疗对大鼠心肌缺血模型再灌注后组织无复流的相关影响。方法：选择标准成年Sprague Dawley大鼠40只（雄性雌性各20只），平均体重（205.6±1.5）g，随机分为对照组和观察组，每组各20只，建立心肌缺血再灌注模型，对照组给予常温处理，观察组则在再灌注结束时晚期给予低温干预，对两组大鼠心肌组织无复流的差异及相关变量进行比较分析。结果：观察组的心肌缺血高危区域所占的百分比平均水平为（16.7±3.5）%，低于对照组的（35.6±2.5）%（P<0.05）；观察组的组织坏死区域所占的百分比平均水平为（23.8±5.1）%，低于对照组的（56.4±3.9）%（P<0.05）。与对照组相比，观察组再灌注结束时心率降低，收缩压和平均血压升高（P<0.05）；两组大鼠心肌染色宏观评价显示心肌梗死面积无明显差异，但观察组无复流的区域小于对照组。结论：在大鼠心肌缺血动物模型中通过再灌注后晚期给予治疗性的低温处理能够显著改善微血管的堵塞，并且此效应与心肌梗死的面积无关。

Effect of Hypothermia on Myocardial No-reflux in the Rat Model of Myocardial Ischemia-reperfusion

ABSTRACT Objective: To investigate the related effects of hypothermia on myocardial no-reflow in the rat model of myocardial ischemia-reperfusion. Methods: 40 adult Sprague Dawley rats (20 males and 20 females) were selected, the average body weight were (205.6±1.5) g. They were randomly divided into control group and observation group, 20 for each group. The model of myocardial ischemia-reperfusion was established, and the control group was treated with normal temperature. The observation group was given low temperature intervention at the end of reperfusion. The differences of myocardial tissue no-reflow and the related variables were compared and analyzed. Results: The average percentage of high-risk areas of myocardial ischemia in the observation group was (16.7±3.5)%, which was lower than that of the control group (35.6±2.5)%(P<0.05). The average percentage of tissue necrosis area in the observation group was (23.8±5.1)%, which was lower than that in the control group (56.4±3.9)% (P<0.05). Compared with the control group, the heart rate decreased, systolic blood pressure and mean blood pressure increased at the end of reperfusion in the observation group(P<0.05). The macroscopic evaluation of myocardial staining showed no significant difference in infarct size between the two groups, but the area no-reflow in the observation group was smaller than that in the control group. Conclusion: Late administration of therapeutic hypothermia after reperfusion in a rat model of myocardial ischemia in rats can significantly improve microvascular occlusion, and this effect is independent of the area of myocardial infarction.