低氧及跑台运动对大鼠左心室肌线粒体超微结构的影响

关键词：低氧  运动  线粒体  超微结构

Keywords:hypoxia  exercise  mitochondria  ultrastructure

摘要：

      摘要 目的：观察低氧及低氧复合跑台运动后大鼠左心室肌细胞内线粒体超微结构的变化，探讨低氧及运动训练对心肌线粒体的影响。 方法：成年雄性SD大鼠40只，随机分为4组：常氧对照组、常氧运动组、低氧对照组及低氧运动组。用MPA-心功能分析系统记录血压和心率，用透射电镜观察各组大鼠心肌线粒体的超微结构。 结果：常氧对照组：线粒体结构完整，平行排列。常氧运动组：线粒体数量增加，体积增大，轻度水肿。低氧对照组：线粒体排列紊乱，挤压变形，嵴断裂，外膜增厚。低氧运动组：线粒体平行排列，基质增多，部分线粒体结构不清，肌膜尚清晰。 结论：低氧导致左心室肌线粒体结构严重破坏，运动使线粒体数量增加，体积增大。适度的运动训练可明显改善低氧对大鼠心肌线粒体的损伤，对心脏有一定的保护作用。

Abstract:

      Abstract Objective: To study the changes in mitochondrial ultrastructure in left ventricle of rats after hypoxia and treadmill exercise. Method: Forty adult male Sprague-Dawley rats were randomly divided into 4 groups: normoxia control group,normoxia exercise group,hypoxia control group and hypoxia exercise group. Blood pressure and heart rate were recorded with MPA-heart function analysis system. Result: In normoxia control group, mitochondria showed normal appearance and high organization. In normoxia exercise group, quantity and volume of mitochondria increased, with light swelling. In hypoxia control group, mitochondria arranged disorderly and extruded deformedly, mitochondrial cristae breaked and outer membrane thickened. In hypoxia exercise group, mitochondria arranged regularly, matrix increased, structures of partial mitochondria were unclear, sarcolemma were almost clear. Conclusion: Hypoxia destroys the mitochondrial ultrastructures in left ventricle, while exercise training can increase the amouat and volume of mitochondria. Moderate exercise can relieve the hypoxia-induced mitochondrial damages and exerts a protective effect on damaged myocardium.