Branched-chain α-keto acid dehydrogenase kinase content in rat skeletal muscle is decreased by endurance training

Abstract

The activity state of branched-chain α-keto acid dehydrogenase complex in skeletal muscle was elevated by running exercise in trained and untrained rats, but level of this elevation was significantly greater in the former than in the latter. To elucidate the mechanism of the training effect on the exercise-induced activation of the complex, a protein amount of branched chain α-keto acid dehydrogenase kinase, which is responsible for inactivation of the complex by phosphorylation, in the muscle was measured by the Western blot analysis. Endurance training decreased the content of the kinase protein in the muscle by ~30%, suggesting that this decrease is involved in the mechanisms for greater activation of the complex by exercise in trained rats.