Phillips S M, Han X X, Green H J, Bonen A
Department of Kinesiology, University of Waterloo, Ontario, Canada.
Am J Physiol. 1996 Mar;270(3 Pt 1):E456-62. doi: 10.1152/ajpendo.1996.270.3.E456.
We investigated the time course of training-induced changes in the expression of GLUT-1 and GLUT-4 in human skeletal muscle. Seven healthy males trained for 2 h/day (approximately 60% pretraining VO2peak) for 31 days (31D). Muscle biopsies were obtained before training (PRE) and after 5 (5D) and 31 days (31D) of training. Training resulted in progressive increases in muscle GLUT-4 with increasing training duration (PRE<5D<31D; P<0.01). Muscle GLUT-1 content was also increased (P<0.05) after training; however, the increase was not observed until 31D (131%). Increases in muscle hexokinase (HK) activity were complete by 5D (P<0.01). Muscle malate dehydrogenase activity was not elevated after 5D of training but was increased (+35%; P<0.01) at 31D. Results from this study show that increases in both GLUT-4 and HK represent early training-induced adaptations to prolonged exercise training. As training progresses, further increases in GLUT-4, but not HK, occur in conjunction with an increase in muscle mitochondrial potential and GLUT-1.
我们研究了训练诱导的人体骨骼肌中葡萄糖转运蛋白1（GLUT-1）和葡萄糖转运蛋白4（GLUT-4）表达变化的时间进程。七名健康男性每天训练2小时（约为训练前最大摄氧量的60%），持续31天（31D）。在训练前（PRE）以及训练5天（5D）和31天（31D）后采集肌肉活检样本。随着训练时间的增加，训练导致肌肉GLUT-4逐渐增加（PRE<5D<31D；P<0.01）。训练后肌肉GLUT-1含量也增加了（P<0.05）；然而，直到31D才观察到增加（增加131%）。肌肉己糖激酶（HK）活性在5D时增加完成（P<0.01）。训练5天后肌肉苹果酸脱氢酶活性未升高，但在31D时增加（+35%；P<0.01）。本研究结果表明，GLUT-4和HK的增加代表了训练诱导的对长时间运动训练的早期适应。随着训练的进行，GLUT-4进一步增加，但HK没有，同时肌肉线粒体电位和GLUT-1增加。
