补充L-肉碱对运动大鼠骨骼肌能量生成变化的影响

Influence of L-carnitine Supplementation on the Energy Generation of Well-trained SD Rats’ Mitochondria of Skeletal Muscle

目的:本研究通过对SD大鼠外源性补充左旋肉碱(L-肉碱)并结合长期游泳训练,观察大鼠骨骼肌肉碱含量、骨骼肌线粒体肉碱脂酰转移酶-I、H+K+-ATP酶活性的变化,分析运动及补充L-肉碱对机体骨骼肌能量消耗与生成变化的影响,为进一步探讨外源性L-肉碱对机体能量代谢影响的作用机制及其应用提供实验依据。方法:健康雄性同龄纯种SD大鼠32只,所有大鼠在适应性饲养一周后,随机分成安静对照组(A组)、单纯运动组(E组),单纯补充L-肉碱组(L组),运动结合补充L-肉碱组(LE),分笼喂养,每组8只。安静对照组和单纯补充L-肉碱组不进行任何运动,单纯运动组和运动结合补充L-肉碱组进行游泳训练,训练时间共持续6周。补充L-肉碱组和训练结合补充L-肉碱组每周训练三次,并于每次游泳训练前1小时补充L-肉碱,安静对照组及单纯训练组自由进食,经6周实验后各组大鼠取出骨骼肌样本分别采用紫外分光光度计,ELISA测定并分析各组大鼠骨骼肌组织线粒体H+K+-ATP酶、CPT-I酶活性变化。结果:与安静对照组相比,单纯运动组大鼠骨骼肌线粒体H+K+-ATP酶、CPT-I酶活性差异无统计学意义(P>0.05);单纯补充L-肉碱组大鼠H+K+-ATP酶、CPT-I酶活性升高,但差异无统计学意义(P>0.05);运动结合补充L-肉碱组大鼠H+K+-ATP酶、CPT-I酶活性的升高具有统计学意义(P<0.05)。与单纯运动组相比,运动结合补充L-肉碱大鼠H+K+-ATP酶、CPT-I酶活性显著升高,并具有统计学意义(P<0.01)。结论:(1)在安静及单纯补充L-肉碱条件下,大鼠运动结合补充L-肉碱后骨骼肌中肉碱含量显著增高,有利于脂酰CoA进入线粒体的速度增加,脂肪酸氧化速度因此加快,ATP能量的生成可较大程度提高。(2)与安静状态下大鼠相比,运动并结合补充L-肉碱后骨骼肌线粒体中H+K+-ATP酶的活性显著升高,且比单纯运动后升高更为显著,提示运动结合补充L-肉碱对骨骼肌线粒体H+K+-ATP酶活性产生的增高效应会进一步促进骨骼肌线粒体的能量代谢。

Objective： By exogenous supplementing L-carnitine （L-camitine） and combined with long-term swimming training, to observe the changes of the SD rat skeletal muscle mitochondrial enzyme activity after exer-cise, effects of exercise training and supplementary cause and mechanism of L-camitine on the impact of energy me-tabolism, in order to provide a valid experimental basis and reference for research to improve the athletic ability of the body and improve the body＇s energy metabolism. Meth-od ： Healthy male peers purebred SD rats 32, all rats in the adaptability of feeding after a week, according to the pilot scheme were randomly divided into sedentary control group （group A）, a simple exercise group （group E）, a simple supplement camitine group （group L）, exercise combined with L-camitine （group LE ）, sub-cage feeding, each group is 8. Quiet control group and simply added L-cami-tine does not make any movement, the simple exercise group and exercise combined with L-camitine group swimtraining, the training time for six weeks. Group L and training combined with the supplement L-carnitine group training three times a week, and one hour before each swim training supplement L-carnitine, group A and group E as well normal eating the same amount of rat food, After six weeks of experiments, the rats were decapitated to re-move the blood and skeletal muscle samples, respectively, using a UV spectrophotometer, ELISA, and kits for deter-mination of the rats in each group corresponding blood bio-chemical indices and muscle tissue mitochondrial H^＋K^＋ - ATPase enzymes, CPT-I enzyme activity will be measured and analyzed. Results： After 6 weeks of experiments, compared to the sedentary control group, simple exercise group in rat skeletal muscle mitochondrial H^＋K^＋ -ATP enzyme of CPT-I enzyme activity differences not statistical- ly significant （P 〉 0.05） ; simply supplement L-carnitine in rats H^＋K^＋ - ATP enzyme of CFF-I enzyme activity in-creased （P 〉 0.05）, but the difference was not statistically significant; activity of H^＋K^＋ -ATPasethe and CFF-I en-zyme in group LE increasing has statistically significant （P 〈 0. 05 ）. Compared with t group E, exercise combined with L-carnitine group of H^＋K^＋ - ATPase enzyme, the CFF -I activity was significantly increased, with statistical sig- nificance （P 〈 0. 01 ）. Conclusions ： （ 1 ） Compared to qui- et rats, L-carnitine supplementation does not produce a sig-nificant impact on the rats of CPT-I enzyme activity, but ex-ercise combined with L-carnitine, CFF-I enzyme activity in-creased and is the most obvious, indicating that skeletal muscle cells during exercise may speed up the rate of fatty acid oxidation. （2） Compared to quiet state, L-carnitine supplementation, swiming combined with H^＋K^＋-ATPase activity was significantly increased after supplementary L-carnitine in skeletal muscle mitochondria, suggesting that L-carnitine supplement may be the body of H^＋K^＋ -ATPase ac- tivity increased the effects of promoting skeletal muscle mi- tochondrial energy metabolism.