High respiratory quotient of dog kidney in vivo

¹ Department of Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio

The R.Q. of the dog kidney was determined in vivo in unilaterally nephrectomized dogs during the infusion of a) NaCl, b) -keto acids, c) during acute lactate alkalosis and d) during acute acidosis (HCl or H₂SO₄). The mean (± S.E.) R.Q.'s observed and their statistical significance above unity respectively were a) 1.33 ± 0.07, P < 0.05 (n = 17); b) 1.27 ± 0.08, P < 0.05 (n = 19); c) 1.18 ± 0.08, 0.05 < P < 0.10 (n = 34); and d) 1.14 ± 0.11, P > 0.10 (n = 32). The excess in renal CO₂ production over O₂ consumption is interpreted to indicate that a portion of the kidney utilizes substrates by coupled anaerobic oxidation-reductions yielding CO₂. The two experimental conditions in which maximal (NaCl infusion) and minimal (acidosis) medullary counter-current multiplier activity should occur were also those with the highest and lowest mean renal CO₂ production rates. None of the experimental groups showed any significant changes in O₂ consumption. A relationship between renal anaerobic metabolism as manifested by excess CO₂ production and renal excretory function is postulated.

Note:
With the Technical Assistance of Evelyn Wittmann and Louis Luedders