摘要
目的观察长期体外反搏后心肌结构和功能的变化,评价体外反搏对细胞凋亡的影响。方法雄性Beagle犬12只,随机分为对照组(n=6)和反搏组(n=6)。所有犬用心导管法建立定向冠状动脉闭塞模型3 d后,反搏组犬接受体外反搏处理,每日1h,共6周。利用常规苏木精-伊红(HE)染色和透射电镜观察心肌显微和超微结构的变化。电镜观察细胞凋亡的特征性改变。结果与对照组比较,光镜下反搏组犬受累区域心肌的病理改变程度较轻,电镜观察显示反搏组犬缺血心肌的肌原纤维排列大致整齐,线粒体肿胀不明显,大部分线粒体膜完整,血管内皮细胞基膜完整。未见明显的心肌和血管内皮细胞凋亡的超微结构改变。相反,对照组心肌组织内可见大量心肌及内皮细胞凋亡的特征性改变。此外,体外反搏后,左心室的射血分数(EF)明显改善,心室壁运动能力提高。结论长期体外反搏对保护心肌结构和功能有显著作用,并能拮抗心肌细胞和血管内皮细胞凋亡,有利于心肌功能结构的维护。
Objective To observe the effects of long-term enhanced external counterpulsation （EECP） on myocardial ultra structure and apoptosis in canine model with acute coronary occlusion. Methods Twelve male Beagle dogs were randomly allocated to EECP （ n = 6） and control group （ n = 6）. Experimental coronary occlusion was developed with catheterization for all animals. EECP was applied with one hour per day, 5 days per week after coronary occlusion in the duration of 6 weeks. Hernatoxylin and Eosin staining and transmission electron microscope were taken for the study of pathological and morphological analysis for each dog. Results Under low-power light microscopic examinations, more myocytes and fewer fibrous tissues and collagen materials were found in infarct region of EECP group compared with that of control dogs. The ultrastructural damages of myocytes under transmission electron microscope were less in EECP group compared with that in the control. There were no obvious apoptotic cells existed in the infarct myocardium of EECP group. But more severe ultrastructure changes and apoptotic cells predominantly in myocytes and vascular endothelial cells were frequently found in control group. In addition, the cardiac EF and regional wall motion were significantly improved after EECP compared with that of control. Conclusion Long-terrn EECP may play important roles in protecting cardiac function and structure and preventing cellular apoptosis in coronary occlusive myocardium as well.
出处
《中国心血管杂志》
2006年第6期401-404,407,共5页
Chinese Journal of Cardiovascular Medicine
基金
国家"十五.攻关"(编号:2001BA706B-07)
国家自然科学基金重点项目仪器专项(编号:30127001)资助课题
关键词
体外反搏
心肌缺血
细胞凋亡
犬
Enhanced external counterpulsation
Myocardial ischemia
Apoptosis
Dog
