EFFECTS OF ADRENALECTOMY ON DAILY RHYTHMS IN OXYGEN CONSUMPTION OF TISSUES IN THE GROWING RAT

Abstract

SUMMARY Daily rhythms in oxygen consumption were demonstrated in liver and skeletal muscle of male rats. Rhythms were observed only in skeletal muscle of females and in some cases there appeared to be a sex difference in the overall level of respiration. Respiration rhythms were not found in cardiac muscle of either sex. The effect of adrenalectomy upon the rhythms was examined. This indicated that the adrenal does not determine the phasing of the rhythms but does control the basal level of tissue oxygen uptake.