慢性常压缺氧高二氧化碳对大鼠心肺功能与结构的影响

INFLUENCES OF CHRONIC NORMOBARIC HYPOXIA─HYPERCAPNlA ON CARDIAC AND PULMONARY FUNCTION AND STRUCTURE IN RATS

观察了大鼠于慢性缺氧四周、缺氧高二氧化碳（缺Ｏ２高ＣＯ２）四周及八周后的血流动力学及心肺的组织与超微结构的变化。缺氧四周使肺动脉压及右心室±ｄｐ／ｄｔｍａｘ升高、右心室肥厚、肺血管肌增强、右室心肌的线粒体数量增多及肺毛细血管内皮细胞疏松水肿。缺ＣＯ２高ＣＯ２四周尚可致左心室肥厚。缺Ｏ２高ＣＯ２八周使右室±ｄｐ／ｄｔｍａｘ回降、左右心室肥厚、部分心肌肌丝及肺毛细血管内皮细胞坏死。这些结果提示：慢性常压缺Ｏ２高ＣＯ２性肺动脉高压是较合适的任性肺心病模型。

he hemodynamics,histology and ultrastructure changes of the myocardium and lung wereobserved in the anesthetized male SD rats after having been exposed to chronic hypoxia for fourweeks and to hypoxia─hypercapnia for four weeks and for eight weeks. The results showed thatin the group of hypoxia for four weeks, pulmonary hypertension and right ventricular ± dp/dtmax increased and right ventricular hypertrophy and musculanization strengthened. The amountof mitochondria of the right ventricular myocardium increased, and the endothelial cells of thepulmonary capillary were loose and became edema. Besides, left ventricular hypertrophy broughtabout in the group of hypoxia─hypercapnia for four weeks. In the group of hypoxia─hypercapniafor eight weeks, regressing of RV±dp/dt max, right and left ventricular hypertrophy and necro-sis in some of myofilamants of the right ventricular myocardium and of the endothelial cells ofpulmonary capillary developed.These results suggested that the pulmonary hypertension causedby chronic normobaric hypoxia─hypercapnia be a uitable model of chronic cor pulmonale. Theleft ventricular hypertrophy developed in the rats exposed to hypoxia─hypercapnia.