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Effects of re-feeding after prolonged starvation on pyruvate dehydrogenase activities in heart, diaphragm and selected skeletal muscles of the rat.

ABSTRACT: We investigated the capacity for pyruvate oxidation in skeletal muscle, diaphragm and heart after starvation and re-feeding. Starvation for 48 h decreased pyruvate dehydrogenase (PDH) activity in soleus (by 47%), extensor digitorum longus (64%), gastrocnemius (86%), diaphragm (87%), adductor longus (90%), tibialis anterior (92%) and heart (99%). Chow re-feeding increased PDH activity in all muscles to 43-78% of the fed value within 2 h. However, complete re-activation was not observed for at least 4-6 h, during which time hepatic glycogen was replenished. We discuss the importance of muscle PDH activity in relation to sparing carbohydrate for hepatic glycogen synthesis.

SUBMITTER: Sugden MC

PROVIDER: S-EPMC1133320 | biostudies-other | 1989 Sep

REPOSITORIES: biostudies-other

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Time courses of the responses of pyruvate dehydrogenase activities to short-term starvation in diaphragm and selected skeletal muscles of the rat.

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