Renal Citric Acid Utilization in the Dog

Abstract

The renal uptake, metabolism and excretion of endogenous and exogenous citrate have been determined in unilaterally nephrectomized London cannula preparations with and without the presence of the thyroparathyroid apparatus. The uptake of citrate by the kidney is related to total renal plasma flow and consistently exceeds the extraction of creatinine. Only a small fraction of endogenous citrate removed from the blood passing though the kidney is excreted in the urine. The capacity of the kidney to metabolize circulating citrates is several times the endogenous renal uptake. Thyroparathyroidectomy reduced the endogenous renal uptake of citrate, but not the uptake when the plasma concentration was elevated by citrate infusion.