高住低练对大鼠心肌线粒体活性氧的影响

目的:探讨常压不同低氧(14.5%、12.6%氧含量)环境下(相当于模拟海拔3000m和4000m)高住低练对大鼠心肌线粒体活性氧(ROS)的影响,为运动与低氧适应的应用研究提供参考。方法:120只SD大鼠,随机分为12组,分别为低住安静组、低住低练组、急性高住安静组、急性高住运动组、急性高住低练组、高住安静组和高住低练组,5个高住组又分为常压14.5%氧含量和12.6%含氧量2个亚组。采用二氯荧光素双醋酸盐(DCFH-DA)荧光探针观察线粒体ROS的变化。结果:急性低氧应激后,大鼠心肌线粒体ROS呈上升趋势。与低住安静组相比,模拟海拔3000m和4000m急性高住安静组和急性高住运动组线粒体ROS均显著升高(P<0.05,P<0.01);与低住低练组相比,急性高住运动组均显著升高(P<0.01),模拟海拔4000m高住低练组显著升高(P<0.05);与急性高住运动组相比,模拟海拔3000m急性高住低练组和高住低练组均显著下降(P<0.05),可见模拟海拔3000m高住低练能使ROS生成减少。结果提示:心肌线粒体ROS可能参与低氧适应的形成和发展,高住低练有利于缺氧耐受性的形成。

Effects of Living at High-Training at Low Altitude on Mitochondrial Reactive Oxygen Species in Rats' Myocardium

Objective To study the effects of simulated living at high altitude-training at low altitude(HiLo) on mitochondrial reactive oxygen species(ROS) in myocardium of rats. Methods One hundred and twenty male Sprague-Dawley rats were randomly divided into 12 groups: living-low control group,living low-training low group,acute living high-exercise group,acute living high-training low group,living high control group,living high-training low group, and all living high groups were further divided into two subgroups in accordance with oxygen contents of 14.5% and 12.6%, respectively. ROS were assessed by methods of DCFH-DA. Results Mitochondrial ROS in rat heart increased following hypoxic stress.Comparing with that in living low control group, ROS in acute living high control group (simulated 3000m and 4000m) increased significantly(P<0.05), as well as in acute living high-exercise group (P<0.05). Comparing with that in living low-training low group, ROS increased significantly in acute living high-exercise group (P<0.01) and in living high-training low group (simulated 4000m) (P<0.05). Comparing with that in acute living high-exercise group, ROS in acute living high-training group and in living high-training low group (simulated 3000m) decreased significantly(P<0.05).Conclusion ROS took part in acclimatization to altitude and HiLo improved body hypoxic tolerance.