早期心肌挫伤超微结构变化的实验研究

应用机械式弹性拉力打击器以10.0米／秒速度冲击犬胸骨心前区，引起心肌挫伤。分别对伤后2～5min、30～60min、3h及5h心肌挫伤区超微结构变化进行观察。结果显示：（1）伤后2～5min即见严重的心肌超微结构损害，如肌原纤维撕裂、扭曲变形，肌节过度收缩或I带增宽Z线弯曲、线粒体破裂，部分嵴不清、间质出血并可见游离的线粒体。伤后30～60分钟挫伤心肌肌原纤维溶解、碎裂，线粒体破裂伴嵴消失。伤后3及5h，挫伤区坏死明显，坏死物与红细胞碎片混杂一起，结构不能辨认。（2）同一心脏可有多部位损伤，且损伤程度不均一。

EXPERIMENTAL STUDY ON CHANGES OF EARLY MYOCARDIAL CONTUSION

An experimental animal model of myocardial contusion was established in dogs by impact to the precordial region with mechanical elasticcord propelled impactor at velocity of 10.0m/s. Ultrastruc tural changes of myocardial contusion were obse rved 2~ 5min, 30~ 60min, 3h and 5h after trauma.(1 ) Serious ultrastructural changes of myocardium might be observed 2 ~ 5min post-impact, such as disrupture, distortion, overcontraction or widened I bands with wavy Z lines of myocardial fibrils, broken cristae of mitochondria,bleeding and isolated mitochondria in the interstitium. 30~ 60min after trauma myocardial fibrils dissolved and fragmented and mitochondria disruptured with severely brokencristae within contused myocardium. 3h and 5h after-trauma seriously damaged myocardium,necrotic myofibrils mixed with debris of erythrocytes. The structure of myofibrils was unclear. (2)Degrees of myocardial lesions myocardium varied in defferent parts were detected of a heart.