Oxygen consumption and sodium pump thermogenesis in a developing mammal.
During development the liver undergoes large changes in its oxygen consumption. The energy requirements of the sodium pump (i.e., ouabain-sensitive respiration) would appear to account for a major part of these changes. In very young rats (birth to 9 days), the sodium pump accounted for approximately 50% of a high weight-specific liver metabolism (LMR). In rats greater than or equal to 20 days of age, the sodium pump accounted for a smaller percentage (33%) of a much lower LMR. These changes scaled with body mass. LMR scaled with an allometric slope of -0.258, ouabain-sensitive respiration with a slope of -0.355, and ouabain-insensitive respiration with a slope of -0.194. It is proposed that changes in LMR of rats during development are due primarily to the changing energy requirements of the sodium pump.
Else
P L
PL
Department of Zoology, University of Melbourne, Parkville, Victoria, Australia.
D000375:Aging / Q000378:metabolism; D000818:Animals; D001833:Body Temperature Regulation / Q000502:physiology*; D001835:Body Weight; D004734:Energy Metabolism; D005260:Female; D008099:Liver / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D008297:Male; D009929:Organ Size; D010042:Ouabain / Q000494:pharmacology; D010101:Oxygen Consumption; D051381:Rats; D000254:Sodium-Potassium-Exchanging ATPase / Q000502:physiology*
D010042:Ouabain; D000254:Sodium-Potassium-Exchanging ATPase