MECHANISM OF LOWERING OF THE BASAL METABOLISM DURING ADAPTATION TO HYPOXIA

During adaptation of rats to periodic hypoxia in a pressure chamber the oxygen consumption fell by 40%. This decrease was still found in a state of deep anesthesia and, consequently, it was independent of adaptive changes in cortical regulation of the animals' motor activity. Half of this decrease in oxygen consumption still continued during exposure of the animal to cold, noradrenalin, and 2,4-dinitrophenol (DNP), which uncouples oxidative phosphorylation. The economic utilization of oxygen during adaptation to hypoxia cannot thus be completely explained by an increase in the degree of coupling of oxidation with phosphorylation. © 1979 Plenum Publishing Corporation.