Rates of oxygen consumption and of anaerobic glycolysis in renal cortex and medulla of adult and new-born rats and guinea-pigs

摘要

1. Rates of oxygen uptake and of anaerobic glycolysis were estimated in slices from the renal cortex and medulla (a) of adult rats and guinea-pigs, (b) of new-born (1-, 5- and 21-day-old) rats and of guinea-pigs of 1, 12, 21, 24 and 120 hr age.2. In the adult rat, QO2 values for the cortex were 12·55 ± 0·20 (22) and for the medulla: 8·56 ± 0·17 (22) μl./hr.mg dry weight, while in the new-born rat (24 hr old) they were 10·99 ± 0·46 (12) and 9·33 ± 0·18 (9) μl./hr.mg dry weight respectively.3. Values for QCO2^N2 (anaerobic glycolysis) in the 14 hr old new-born rat were in the renal cortex 9·65 ± 0·35 (5) and in the medulla 7·39 ± 0·43 (5) μl./hr.mg dry weight; while in the adult they were 2·25 ± 0·08 (16) and 5·76 ± 0·14 (16) μl./hr.mg dry weight, respectively.4. In the adult guinea-pig values for QCO2^N2 were of the same order as in the adult rat, though the rate of O2 uptake was for the cortex 8·12 ± 0·22 (12) and for the medulla 5·02 ± 0·23 (11) μl./hr.mg dry weight.5. Though the QO2 values in the renal cortex and medulla were smaller in the 1 hr old new-born guinea-pig, they were already increasing in the 12 hr old neonate.6. The results are discussed in the light of enzyme changes occurring during the process of maturation of the nephron as indicated by histochemical observations.