紫草提取物对疲劳大鼠的肝组织保护作用

Hepatoprotective Effect of Gromwell Extract in Fatigue Rats

目的:通过观测耐力训练大鼠力竭和恢复24 h后肝组织及线粒体生化指标的变化,探讨紫草提取物在保肝护肝、提高运动能力、延缓运动疲劳、促进疲劳后恢复方面的生物学机理。方法:选取40只Sprague-Dawley(SD)雄性大鼠,随机分为5组,每组8只:训练对照组(A组)、运动力竭组(B组)、力竭恢复组(C组)、加药力竭组(D组)、加药恢复组(E组)。5组大鼠按照训练模型进行为期6周的跑台耐力训练,第6周的最后1 d,A组大鼠不进行训练,在安静状态下处死并进行样本处理和指标测定;B、C、D、E组大鼠进行一次性力竭运动后,处死B、D组大鼠并进行样本处理和指标测定;24 h后,处死C、E组大鼠并进行样本处理和指标测定。结果:大鼠在力竭运动后,肝组织抗氧化能力显著下降(P<0.05),一氧化氮合酶(nitric oxide synthase,NOS)活性和NO含量极显著降低(P<0.01),线粒体Na+/K+-ATPase、Ca2+/Mg2+-ATPase活性显著降低(P<0.05),24 h后,各指标恢复不明显。补充紫草提取物的大鼠在力竭运动后,与运动力竭组大鼠相比,肝组织抗氧化能力、NOS活性和NO含量、线粒体Na+/K+-ATPase、Ca2+/Mg2+-ATPase活性都显著升高(P<0.05);24 h后,各指标基本恢复到基础水平。结论:外源性补充紫草提取物可以有效调节NO的生成平衡,改善大鼠肝组织自由基清除和代谢水平,保护肝线粒体离子泵的活性和功能,能延缓运动疲劳的产生,促进运动后机体功能恢复。

Purpose： To observe changes in hepatic and mitochondrial biochemical parameters in rats previously undergoing exhaustive exercise after 0 and 24 hours of recovery, and subsequently to explore the biological mechanisms of orally administered gromwell root extract（GRE） for protecting the liver, improving exercise performance, mitigating exercise fatigue and accelerating recovery from fatigue in rats. Methods： Totally 40 rats were divided into 5 groups including exercise control group（group A）, exhaustive exercise group（group B）, exhaustive exercise followed by 24 h recovery group（group C）, exhaustive exercise with GRE treatment group（group D）, exhaustive exercise followed by 24 h recovery group with GRE treatment（group E）. The rats from each group were subjected to exercise training for 6 weeks. On the last day of the experimental period, the rats from group A（without exercise training）, B and D（immediately after exercise training） were sacrificed, while those from group C and E were sacrificed at 24 h after exercise training, and samples were collected for the measurement of biochemical parameters. Results： After the exhaustive exercise, the antioxidant capacity of hepatic tissue（P〈0.05）, the activity of nitric oxide synthase（NOS） and the content of NO in hepatic tissue（P〈0.01）, and the activities of Na^＋/K^＋-ATPase and Ca^2＋/Mg^2＋-ATPase in hepatic mitochondria were significantly decreased（P〈0.05）, but these indicators were not significantly restored after subsequent recovery for 24 hours.Compared with group B, the antioxidant capacity of hepatic tissue in rats receiving oral administration of GRE was significantly improved（P〈0.05）, and NOS activity, NO content and the activities of Na^＋/K^＋-ATPase and Ca^2＋/Mg^2＋-ATPase in hepatic mitochondria were also enhanced significantly（P〈0.05）; after 24 hours of recovery, these indicators were restored to the basal levels. Conclusion： Oral supplementation of gromwell root extract can regulate the balance of NO generation, improve the balance of free radical metabolism, protect the activities and functions of ionic pumps, prolong the exhaustive time of endurance-trained rats, and enhance functional recovery from exercise fatigue.