反复力竭性运动后不同时相大鼠心电图的动态改变

The dynamic changes on ECG in different time cases after repeated exhausted exercise in rats

目的:观察大鼠反复力竭性游泳运动前、后不同时相心电图(ECG)的动态改变,以评价运动性心肌损伤的变化规律。方法:采用经典的Thomas的方法通过力竭性游泳运动建立运动性心肌损伤实验动物模型。ECG检测采用DSI植入式心电信号遥测系统。健康无训练的Wistar雄性大鼠24只,尾部负体重2%的负荷,每天游泳运动至力竭状态(一次游泳时间不小于3h),连续1周(7天)。分别于运动前和末次力竭性游泳运动结束后即刻、1h、3h、6h、12h、24h、48h和96h不同时相记录ECG。结果:经1周反复力竭性游泳运动后,大鼠心电图主要发生了两种心肌缺血损伤性ST-T改变(发生率为100%)。①运动后即刻大鼠心电图ST段明显抬高和T波高耸;6h—12h基本恢复;24h—48hST段又有明显抬高,T波幅度升高、高耸;96hST段有所下移、T波幅度恢复但变窄(发生率为79.17%)。②运动后即刻心电图T波明显低平;运动后3h—6hST段有所下移,T波逐渐恢复;12h—24hST段恢复,T波双峰、变宽、高耸;48hST段显著下移,T波再次低平,随后动物发生死亡(发生率为20.83%)。心律不齐发生率为45.83%。结论:反复力竭性运动后不同恢复期,大鼠心电图呈现两次周期性损伤性ST-T改变,说明大鼠心肌存在有早期和延迟性的损伤性改变,运动心电图对运动性心肌损伤具有重要的诊断意义,为临床诊断和康复治疗提供理论依据。

Objective：To study the dynamic changes on electrocardiograms （ECG） in different time periods after exhausted exercise in rats,in order to evaluate the changing rule of exercise-induced myocardial damage. repeated Method：The animal models of exercise-induced myocardial injury were established according to Thomas＇s method. Healthy untrained 24 male Wistar rats,with 2% bodyweight attached to each tail,were forced to swim until exhaustive （swimming time exceeded 3 hours daily） for 1 week. ECG （lead !1 ） was recorded and analyzed with DSI cardio-vascular radiotelemetry system at before exercise and immediately,1,3,6,12,24,48 and 96 hours after exhausted exercise in rats.Result：After 1-week consecutive daily exhausted swimming,the two kinds of ST-T change patterns on ECG were observed as follows in rats （100%）： （1）Compared with pre-exercise,the ECGs revealed ST segment elevating significantly and great risen T waves at immediately after exhausted exercise, and near to normal level 6 hours later, then ST segment re-elevation with high and sharp T wave at 24,48 hours and ST segment depression with narrow T wave at 96 hours post-exercise（79.17%）.（2）The ECGs in rats showed obviously T wave flat at immediately post-exercise, ST segment depression with T wave recovering gradually at 3,6 hours post-exercise,then ST segment recovering with wide and soaring double-peak .T wave associated with T wave fiat at 48 hours post-exercise, at 12,24 hours later,and significant ST segment depression finally the rats died （20.83%）.The arrhythmia takes place （45.83%）. Conehltsion：The ECGs of rats revealed two cyclic ST-T changes in different phases after exhausted exercise. The results suggest that there are early myocardial injury and delayed-onset myocardial injury in rats, Athletic electrocardiogram have an important diagnosis value on myocardial injury induced-exercise.