Zorzano A, Balon T W, Goodman M N, Ruderman N B
Am J Physiol. 1986 Jul;251(1 Pt 1):E21-6. doi: 10.1152/ajpendo.1986.251.1.E21.
After exercise of moderate intensity the ability of insulin to stimulate the uptake of glucose and alpha-aminoisobutyric acid (AIB) in perfused rat muscle is enhanced in a parallel fashion. The present study was designed to examine the effect of intense exercise on the subsequent uptake of these substrates. For this purpose, rats fed ad libitum were run on a treadmill for 50 min at high intensity and glucose and AIB uptake by muscle were then assessed in the isolated perfused hindquarter preparation. In confirmation of previous studies, 30 min after such exercise the absolute rate of glucose uptake in the presence of 20,000 microU/ml of insulin was greater due to additive effects of insulin and prior exercise. A novel finding was that 150 min postexercise the rate of glucose uptake was still increased in the presence of a supramaximal concentration of insulin, but entirely due to an increase in insulin responsiveness. The uptake of AIB and its response to insulin in general paralleled that of glucose. The results indicate that both glucose and AIB uptake by skeletal muscle in the presence of a supramaximal concentration of insulin are increased after intense exercise. They suggest that this is initially due to an additive effect of insulin and exercise and later due to an increase in insulin responsiveness. The findings are compatible with the notion that after exercise insulin is able to recruit or activate glucose (and possibly AIB) transporters in muscle, that it does not affect in the resting state.
进行中等强度运动后，胰岛素刺激灌注大鼠肌肉摄取葡萄糖和α-氨基异丁酸（AIB）的能力会以平行方式增强。本研究旨在检验高强度运动对这些底物后续摄取的影响。为此，将自由进食的大鼠在跑步机上进行50分钟的高强度跑步，然后在离体灌注后肢标本中评估肌肉对葡萄糖和AIB的摄取。正如先前研究所证实的，在进行此类运动30分钟后，由于胰岛素和先前运动的累加效应，在胰岛素浓度为20,000微单位/毫升时，葡萄糖摄取的绝对速率更高。一个新发现是，运动后150分钟，在胰岛素超最大浓度存在的情况下，葡萄糖摄取速率仍然增加，但完全是由于胰岛素反应性增加所致。AIB的摄取及其对胰岛素的反应总体上与葡萄糖的情况相似。结果表明，在胰岛素超最大浓度存在的情况下，高强度运动后骨骼肌对葡萄糖和AIB的摄取均增加。研究结果表明，这最初是由于胰岛素和运动的累加效应，后来是由于胰岛素反应性增加。这些发现与运动后胰岛素能够募集或激活肌肉中在静息状态下不起作用的葡萄糖（可能还有AIB）转运蛋白这一观点相符。
