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目的：观察缺氧及停止缺氧后对大鼠心肌血流量的影响。方法：３４只Ｗｉｓｔａｒ大鼠，随机分为４组：①平原对照组；②急性缺氧组；③慢性缺氧组；④返回平原组。以放射性生物微球法测定心肌血流量。结果：急性缺氧引起ＰａＯ２、心输出量及氧运送量降低，但左、右心室心肌血流量明显增加；慢性缺氧时右心室收缩压、血球压积、血液粘滞性及右心室重量指数明显增加，而心肌血流量接近正常。停止缺氧３０ｄ后，上述所有指标均与平原对照组无显著差别。结论：急性缺氧引起心肌血流量增加；慢性缺氧心肌血流量恢复正常，这可能是红细胞增多及血管中层增厚的结果。高原缺氧引起心血管变化是可逆性改变。
Objective: To observe the effect of hypoxia and hypoxia on myocardial blood flow in rats. Methods: Thirty-four Wistar rats were randomly divided into four groups: ① plain control group; ② acute hypoxia group; ③ chronic hypoxia group; ④ return to plain group. Myocardial blood flow was measured by radioactive microspheres method. Results: Acute hypoxia caused PaO2, cardiac output and oxygen transport decreased, but the left and right ventricular myocardial blood flow increased significantly; chronic hypoxia right ventricular systolic pressure, hematocrit, blood viscosity and right ventricular mass index Significant increase, while myocardial blood flow close to normal. After 30 days of hypoxia, all the above indexes were not significantly different from those of plain control group. CONCLUSION: Acute hypoxia causes an increase in myocardial blood flow; blood flow returned to normal in chronic hypoxic myocardium, which may be the result of increased erythrocytes and thickening of the middle vascular layer. Altered hypoxia caused cardiovascular changes are reversible changes.