酒精对心肌细胞超微结构及细胞色素C 氧化酶活性的影响

目的：通过给小鼠腹腔内注射不同浓度酒精，建立大量饮酒的动物模型，探讨酒精对心脏毒性作用的机理。方法：应用电镜技术观察心肌细胞的超微结构变化，以及酶细胞化学染色方法观察细胞色素C氧化酶(cytochrom C oxidase，Cox)活性的变化。结果：透射电镜下，实验各组心肌细胞肌原纤维排列紊乱，出现空泡，肌丝溶解，线粒体肿胀，嵴断裂甚至消失，细胞核形状不规则，部分染色质浓缩，边集于核膜下，呈斑块状；定位于线粒体内膜和嵴上的Cox活性减弱，电子密度降低。结论：酒精可以使心肌细胞超微结构发生异常改变，并且使线粒体上Cox活性减弱，从而导致心肌细胞结构和功能的改变。

Effect of alcohol on ultrastructure of cardiac muscle cell and the activity of cytochrome C oxidase

Objectives:We established an experimental animal model of excessive drinking of alcohol by giving different concentration of alcohol to healthy mice. The ultrastructural alterations and the changes of the activity of cytochrome C oxidase (Cox) in myocardial cell were investigated. Results:Under the transmission electron microscope (TEM) we found that the myofilaments in alcohol-treated groups arranged irregularly, some vacuoles and dissolved myofilaments could be observed. Most of the mitochondria swollen, the cristae of mitochondria ruptured, or even disappeared. The nuclei were irregular and some of them showed condensation and margination of chromatin. Cytochemically, the Cox located on the inner membrane and cristae of normal mitochondria. In contrast to the normal cardiac muscle cell, the electron density of Cox in all alcohol-treated groups reduced, and most of mitochondria were devoid of the reaction products. Conclusions:The effect of alcohol on the ultrastructure of myocardial muscle cell appeared remarkablely. And alcohol could decrease the enzyme activity of Cox in mitochondria, and finally induced the ultrastructural and functional alteration of myocardial cell.