运动性心肌肥大心脏毛细血管超微结构的变化

目的探讨运动性心肌肥大时，心脏毛细血管的变化，揭示运动性心肌肥大的病理改变。方法雄性SD大鼠18只，对照组不训练；有氧训练组每天训练75min；过度训练组大鼠尾部负重(体重的5％)，每天训练180min。每周5d，共12周。取材后电镜观察。结果有氧训练后，大鼠心脏的毛细血管发生管腔扩大、管壁增厚、内皮细胞线粒啼数目增加、内皮细胞生长活跃等适应性变化。过度训练组大鼠出现心肌毛细血管不规则，壁管皱褶和内壁的指状突起较多；内皮细胞线粒体明显肿胀、嵴结构紊乱；胞质内含的吞饮小泡数目增加、体积较大；细胞核不规则，密度不均匀，核膜皱褶明显；基底膜明显增厚且模糊不清等病理性变化。结论运动训练可使心脏的毛细血管发生适应性改变和病理性损害，运动强度适合时以适应性变化为主，强度过大则以病理性改变明显。

The ultrastructure change of heart capillary in athlete's heart

OBJECTIVE: To see the change of capillary of heart in Athlete's Heart, so that to discover the mechanism of pathologic change. METHOD: 18 male SD rats were separated randomly into control group (without any exercise), aerobic exercise group (swimming for 75 min every day), and overload group (swimming for 180 min with 5% weight of its body every day). After 5 days per week, 12 weeks, exercise training stopped and heart of rats were observed under Transmission Electron Microscope. RESULTS: In aerobic exercise group, the capillary cavities in heart expand, the walls of capillary become thick; the number of mitochondrions increases; endothelium cells become active in growth. However, after overload exercise, the walls of capillary codkle and protuberances appear. The mitochondrions swell and the cristae become disorder. Most of endosomes expand and their number increases. The karyons become abnormity in shape and uniformity in electronic density, besides the nuclear envelope cockle. The basilar membranes become thick and unclear. CONCLUSION: After exercise training, both physical and pathologic changes in heart capillary are found. In suitable exercises group, the capillaries change physically; the pathologic changes are becoming visible after overload exercise however.