Increased span of oxido-reduction states between pyridine nucleotide and cytochrome c oxidase in the regenerating rabbit liver as measured by arterial ketone body ratio and near-infrared spectroscopy.
Oxido-reduction states of intramitochondrial pyridine nucleotide and cytochrome c oxidase and oxygen saturation of hemoglobin in the regenerating rabbit liver were studied with arterial ketone body ratio and tissue near-infrared spectroscopy. Arterial ketone body ratio (acetoacetate/beta-hydroxybutyrate), which reflects the oxido-reduction states of the intramitochondrial pyridine nucleotide (NAD+/NADH), was reduced from the control value of 0.93 +/- 0.09 to 0.42 +/- 0.03 12 h after 70% hepatectomy, while the oxido-reduction states of cytochrome c oxidase and the oxygen saturation of hemoglobin did not change. The velocity of ATP synthesis, as measured by state 3 respiration and ADP/O ratio in isolated mitochondria, increased by 61.4% 24 h after hepatectomy. These results support the near-equilibrium theory that an increased span in oxido-reduction state between pyridine nucleotide and cytochrome c oxidase drives mitochondrial ATP synthesis.
Tanaka
A
A
Second Department of Surgery, Faculty of Medicine, Kyoto University, Japan.
Kitai
T
T
Tokuka
A
A
Inomoto
T
T
Kim
H J
HJ
Tanaka
K
K
Yamaoka
Y
Y
Ozawa
K
K
D000818:Animals; D003576:Electron Transport Complex IV / Q000378:metabolism*; D006498:Hepatectomy; D006499:Hepatic Artery; D007657:Ketone Bodies / Q000097:blood*; D008115:Liver Regeneration / Q000502:physiology*; D008297:Male; D008930:Mitochondria, Liver / Q000378:metabolism; D009243:NAD / Q000378:metabolism*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism; D010108:Oxyhemoglobins / Q000378:metabolism; D010766:Phosphorylation; D011817:Rabbits; D013055:Spectrophotometry, Infrared
D007657:Ketone Bodies; D010108:Oxyhemoglobins; D009243:NAD; D003576:Electron Transport Complex IV; D010100:Oxygen