不同运动负荷大鼠心脏血流动力学变化对左心室内皮细胞形态影响的实验研究

EXPERIMENTAL STUDY OF EFFECTS OF HEMODYNAMIC ALTERATIONS ON LEFT VENTRICLE ENDOTHELIAL CELL MORPHOLOGY IN RATS UNDER DIFFERENT EXERCISE LOADS

采用Ｓ－５７０型扫描电镜和ＲＭ－６２００多道生理记录仪观察分析了大鼠不同运动条件下的心脏血流动力学参数及左心室几何构型和内皮细胞形态变化。结果表明，一般运动负荷导致心脏发生生理性肥大，左心室血流动力学指标升高，左心室流出道内皮细胞由于壁面切应力作用呈流畅梭形，其排列方向与血流方向一致，左心室心尖部由于涡流及二次流作用，内皮细胞呈现卵石样外观，形态各异，排列无序；运动超负荷导致心脏肥大的同时左心室血流动力学指标降低，心脏发生缺血缺氧性损伤，左心室流出道内皮细胞过度拉伸，个别内皮细胞损伤，左心室心尖部内皮细胞损伤严重，红细胞及血小板粘附。提示运动超负荷左心室内皮细胞损伤的病理生理机制主要是由左室壁面切应力。

The present study analyses hemodynamic parameters and left ventricle(LV) geometric configuration and endothelial cell(EC) morphology using S-570 scanning electron-microscopy and RM-6200 polygraph under different exercise loads.Results show that general load exercise can lead to physiological cardiac hypertrophy,elevation of LV hemodynamic indicators,shuttle-shaped LV efferent tract ECs arranging consistent with blood flow direction and pebble-shaped LV apex ECs with disorder arrangement.Results also show that overload exercise can lead to pathological cardiac hypertrophy,decrease in LV hemodynamic indicators,ischemic and anoxic cardiac injury,overextention and injury of LV efferent tract ECs,serious injury of LV apex ECs and adherence of red blood cell and platelet.The paper indicates that pathophysiological mechanisms of injury of LV ECs are the tangent stress,vortex flow,hypostasis,ischemic and anoxic subendocardial in the LV wall after overload exercise.