Renal Clearance of Citric Acid in the Dog. ∗

Summary

The clearance of citric acid under control conditions was generally less than 1 ml/min., being less than 3% of the filtration clearance. Its clearance was markedly elevated after administration of BHCO₃, due chiefly to less absorption by the renal tubules. Administration of citric acid was followed by a comparable elevation of clearance accompanied by an increase both in the filtered load and the amount absorbed by the tubules. Data indicated that the tubular absorption of citric acid was not reduced by ascorbic acid. Administration of potassium did not increase the citrate clearance.