Hepatic gluconeogenesis and mitochondrial function during hibernation.

S C Gehnrich; J R Aprille

doi:10.1016/0305-0491(88)90107-1

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Hepatic gluconeogenesis and mitochondrial function during hibernation.

S C Gehnrich·J R Aprille

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Abstract

1. The aim of these studies was to investigate a mitochondrial basis for changes in gluconeogenesis during hibernation. 2. State 3 respiration rates in liver mitochondria from hibernating ground squirrels were reduced by 62-66%. The limiting reaction appeared to be electron transport, particularly in respiratory complex III. 3. The mitochondrial ATP + ADP + AMP content was reduced by 29% during hibernation; cellular adenine nucleotide content was unchanged. 4. Pyruvate carboxylation in intact mitochondria was decreased 75% during hibernation, although total pyruvate carboxylase activity was not lower. 5. Rates of gluconeogenesis in intact hepatocytes isolated from hibernators were lower than in cells from non-hibernators.

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Adenine Nucleotides Animals Electron Transport Gluconeogenesis Hibernation In Vitro Techniques Liver Mitochondria, Liver Oxygen Consumption Journal Article Research Support, U.S. Gov't, P.H.S.

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S C Gehnrich, J R Aprille. 1988. Hepatic gluconeogenesis and mitochondrial function during hibernation.. https://doi.org/10.1016/0305-0491(88)90107-1

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