The renal accumulation of urate and p-aminohippurate in the rabbit.

1. During intravenous infusion of urate and p-aminohippurate (PAH), the concentration of these two substances in cortex tissue of rabbit kidney exceeded the corresponding plasma concentration.2. Following the administration of 2,4-dinitrophenol, fumarate, succinate, probenecid, and salicylate, accumulation of urate in kidney cortex and renal net secretion of urate were abolished. The accumulation and secretion of PAH were only partially inhibited after infusion of these compounds.3. The renal accumulation of urate was reduced in relation to the inhibition of urate excretion during infusion of various amounts of PAH.4. The combined data indicate a correlation between renal accumulation and excretion of urate and PAH. It appears likely that accumulation of urate and PAH in vivo is due to tubular secretion of these two substances, although in the case of urate a small contribution from tubular reabsorption of urate cannot be excluded.