Espinal J, Dohm G L, Newsholme E A
Biochem J. 1983 May 15;212(2):453-8. doi: 10.1042/bj2120453.
The half-maximal stimulation of the rates of glycolysis and glycogen synthesis in soleus-muscle strips from sedentary animals occurred at a concentration of insulin of about 100 microunits/ml. In soleus-muscle strips from exercise-trained rats (5 weeks of treadmill training), half-maximal stimulation of the rate of glycolysis occurred at about 10 microunits of insulin/ml, whereas that for glycogen synthesis occurred between 10 and 100 microunits of insulin/ml. The sensitivity of glycolysis to insulin after exercise training is similar to that of adipose tissue from sedentary animals. This finding suggests that, in sedentary animals, the effects of normal changes in insulin concentration may affect muscle primarily indirectly via the anti-lipolytic effect on adipose tissue, whereas after training insulin may effect the rate of glycolysis in muscle directly. A single period of exercise did not change the sensitivity of glycolysis in soleus muscle to insulin, nor probably that of glycogen synthesis. It is suggested that the improvement in insulin sensitivity of glycolysis in muscle caused by exercise-training could account, in part, for the well-established improvement in glucose tolerance and insulin sensitivity observed in man and rats after exercise-training.
对于久坐不动的动物比目鱼肌条中糖酵解速率和糖原合成速率而言，胰岛素浓度约为100微单位/毫升时出现半数最大刺激。在经过运动训练的大鼠（5周跑步机训练）的比目鱼肌条中，糖酵解速率的半数最大刺激出现在胰岛素浓度约为10微单位/毫升时，而糖原合成的半数最大刺激出现在胰岛素浓度10至100微单位/毫升之间。运动训练后糖酵解对胰岛素的敏感性与久坐不动的动物的脂肪组织相似。这一发现表明，在久坐不动的动物中，胰岛素浓度的正常变化的影响可能主要通过对脂肪组织的抗脂解作用间接影响肌肉，而训练后胰岛素可能直接影响肌肉中的糖酵解速率。单次运动并未改变比目鱼肌中糖酵解对胰岛素的敏感性，糖原合成的敏感性可能也未改变。有人提出，运动训练引起的肌肉中糖酵解对胰岛素敏感性的改善，可能部分解释了在人和大鼠运动训练后观察到的糖耐量和胰岛素敏感性的公认改善。
