补充谷氨酰胺对耐力训练大鼠运动能力及血清胰岛素样生长因子-1的影响

Effects of Glutamine Supplementation on Physical Performance and Insulin-Like Growth Factor-1 of Rats

通过观察补充谷氨酰胺(Gln)对胰岛素样生长因子-1(IGF-1)及运动能力之间的相互关系,探讨补充Gln促进机体运动能力的内分泌机制。为运动营养补剂的开发和应用,特别是氨基酸的补充提供一定的实验依据,从而使营养补充更为科学和合理。研究对象和方法:雄性SD大鼠,训练组16只、训练+Gln组16只。训练+Gln组按2g/kg体重给予Gln。进行耐力运动训练5周。5周后各组随机取8只,进行跑台力竭运动,并记录达力竭时的运动距离。同时所有大鼠断头处死,测试股四头肌蛋白质含量,血清生长激素(GH)水平和血清IGF-1水平。结果显示:1)跑台运动距离:训练+Gln组的大于训练组[(1995.0±29.6)m vs.(1697.5±170.7)m,P<0.01)];2)股四头肌蛋白质含量:大鼠运动至力竭后,训练+Gln组运动后低于训练组;3)血清GH含量:大鼠运动至力竭后,训练+Gln组运动后低于训练组;4)血清IGF-1浓度:未进行力竭运动的训练+Gln组大鼠与训练组无差异;5)力竭运动后,训练+Gln组的浓度高于训练组[(1223.6±197.1)ng/ml vs.(879.4±197.5)ng/mg,P<0.01]大鼠跑台运动至力竭时的运动距离与血清IGF-1成正相关(r=0.7336,P<0.01)。结论:长期补充Gln可以显著提高大鼠耐力运动能力;却没有提高肌肉蛋白质含量和GH含量;而补充Gln为运动大鼠合成IGF-1提供了充分的原料支持和良好的内环境,而提高了血清IGF-1含量。血清IGF-1水平和大鼠力竭运动能力呈正相关,提示补充Gln促进IGF-1合成是增强机体运动能力的重要内分泌机制之一。

Objective：The study aims to examine the correlation of Glutamine（Gln）on the physical performance of rats and insulin-like growth factor-1（IGF-1）.In order to discuss the endocrine mechanism which promote athletic ability through Gln supplement.Methods：32 male SD rats were divided into training group and training plus Gln group（16 rats per group）.The training plus Gln group were supplied with Gln 2g/kg weight.All of the rats were forced with treadmill running in 5 weeks.Eventually,eight rats of each group were selected randomly;they were forced with exhaustion treadmill running,the running distance was recorded.All of the rats were decollated.The serum IGF-1 were measured,respectively.Results：Distance of exhaustion treadmill running：the training plus Gln group was longer than training group[（1995.0±29.6）m vs.（1697.5±170.7）m,P0.01）].The amounts of protein of stock four muscles：The protein amount of training plus Gln group with exhaustion treadmill running was lower than that of training group.The GH serum concentration：the concentration of training plus Gln group with exhaustion treadmill running was lower than that of training group.The IGF-1 serum concentration：the concentration of the training plus Gln group with exhaustion treadmill running was higher than that of the training group [（1223.6±197.1）ng/ml vs.（879.4±197.5）ng/mg,P〈0.01].The results revealed high correlation between running distance with how long the rats proceeded exhaust exercise and IGF-1 serum concentration（r=0.7336,P〈0.01）.Conclusion：The supplementation of Gln can improve the exercise ability evidently,it can also increase IGF-1 level remarkably,which hint the serum IGF-1 produce the negative feedback cause the result.Gln Complementing can improve IGF-1 level remarkably and the correlation between IGF-1 and exercise ability is positive,which means serum IGF-1improvement can improve exercise ability by complementing Gln.