重复高+GZ应激对大鼠心肌超微结构的损伤效应

目的：研究重复高＋Gz应激对大鼠心肌超微结构的影响，建立高＋Gz致心肌损伤的动物实验模型。方法：24只雄性Wistar大鼠随机分为实验＋1Gz组、＋10Gz组与正常对照组，每组8只。＋1Gz组：＋1Gz暴露5min/d,3d／周，共3周；＋10Gz组：＋10Gz暴露30s/次，5次／d，3d／周，共3周；对照组不爱加速度作用。实验组大鼠于末次＋Gz实验后次日断头处死，迅速从每鼠左室心尖部切取5小块心肌组织，常规透射电镜制样、观察。结果：＋1Gz组心肌结构无明显病变，与对照组接近。＋10Gz组心肌细胞基质水肿，肌原纤维离散，线粒体变性，闰盘结构解离。间质血管内皮水肿，血管腔内血小板聚集、附壁。结论：重复高＋Gz应激可致明显的大鼠心肌结构损伤。

Ultrastructural change of rat heart following repeated high +GZ stress

Objective To observe the effect of repeated high G Z stress on ultrastructure of rat heart and try to set up an animal model of high G Z stress induced myocardial injury. Method Twenty fo ur male Wistar rats were randomly divided into three groups: control group, 1 G Z group and 10 G Z group (n=8 for each). The rats of 10 G Z group were exposed to five plateaus at 10 G Z for 30 s with 1 G Z 1min intervals,3 tim es a week, for 3 weeks,while rats of 1 G Z group subjected to 1 G Z for 5 mi m daily. The control group didn't undergo acceleration stress. The rats were dec apitated in the next day after the last centrifuge run and five small pieces of myocardium were immediately dissected from cardiac apex of left ventricles for u ltrastructural examination using transmission electron microscope. Resu lt The ultrastructural changes of the cardiac muscle were observed in r ats of 10 G Z group, including, stroma edema of myocardial cells, myofibril di sorder, mitochondrion degeneration, intercalated disc dissociation, endothelium edema and platelet aggregating in lumen of blood vessel.The ulstructure in rats of 1 G Z group was essentially normal. Conclusion Repeated h igh G Z stress can induce significant damage of the cardiac muscle ultrastruct ure in rats.