Winder W W, Baldwin K M, Holloszy J O
Can J Physiol Pharmacol. 1975 Feb;53(1):86-91. doi: 10.1139/y75-011.
During and after strenuous prolonged exercise, sedentary individuals develop high blood levels of acetoacetate and beta-hydroxybutyrate whereas exercise-trained animals and human subjects do not. We have investigated the possibility that exercise training can increase the capacity of skeletal muscle to oxidize ketones. In this study we measured rates of D-beta[3-14-C]-hydroxybutyrate and [3-14-C]acetoacetate oxidation, and the levels of activity of the enzymes involved in the oxidation of ketones in homogenates of gastrocnemius muscles of exercise-trained and of untrained male rats. The trained animals had markedly lower blood ketone levels immediately and 60 min after a 90 min long bout of exercise than did the sedentary animals. The rates of D-beta-[13-14C]hydroxybutryate and [3-14-C]acetoacetate oxidation were twice as high in homogenates of muscles from the trained as compared to the sedentary rats. The increases in levels of activity in gastrocnemius muscle in response to the exercise program were: beta-hydroxybutyrate dehydrogenase threefold; 3-ketoacid CoA-transferase twofold; and acetoacetyl-CoA thiolase 55%. This exercise-induced increase in the capacity of skeletal muscle to oxidize ketones could play a role in preventing development of ketosis in the physically trained animal during and following prolonged strenuous exercise.
在剧烈的长时间运动期间及之后，久坐不动的个体血液中乙酰乙酸和β-羟基丁酸水平会升高，而经过运动训练的动物和人类受试者则不会。我们研究了运动训练是否能提高骨骼肌氧化酮体的能力。在本研究中，我们测量了D-β[3-¹⁴C]-羟基丁酸和[3-¹⁴C]乙酰乙酸的氧化速率，以及运动训练的和未训练的雄性大鼠腓肠肌匀浆中参与酮体氧化的酶的活性水平。训练过的动物在90分钟长时间运动后立即以及60分钟后，血液中的酮体水平明显低于久坐不动的动物。与久坐不动的大鼠相比，训练过的大鼠肌肉匀浆中D-β-[13-¹⁴C]羟基丁酸和[3-¹⁴C]乙酰乙酸的氧化速率高出两倍。运动训练后腓肠肌中酶活性水平的增加情况如下：β-羟基丁酸脱氢酶增加了三倍；3-酮酸辅酶A转移酶增加了两倍；乙酰乙酰辅酶A硫解酶增加了55%。运动诱导的骨骼肌氧化酮体能力的增加，可能在防止经过体能训练的动物在长时间剧烈运动期间及之后发生酮症方面发挥作用。
