Renal tubular secretion of uric acid in the mongrel dog.

Abstract

Renal tubular secretion of uric acid was demonstrated in mongrel dogs receiving sodium urate intravenously when an osmotic diuresis was induced by the administration of mannitol. Under these conditions the excretion of urate was greatly augmented and in the majority of experiments the renal clearance of urate exceeded the clearance of creatinine. The high rate of excretion was attributed to a combination of tubular secretion and reduced urate reabsorption, the latter resulting from osmotic diuresis. The administration of probenecid at the height of diuresis tended to reduce the clearance of urate, suggesting that this drug may inhibit tubular secretion of urate. A study of the effect of urinary pH on uric acid excretion indicated that this acid is not excreted by nonionic diffusion.