Excretion of uric acid in the kidney is carried out with the assistance of uric acid transporters, and the transporters are divided into two categories: urate reabsorption transporters and urate excretion transporters. Urate reabsorption transporters have three members, urate anion transporter 1 (URAT1), organic anion transporter 4 (OAT4) and glucose transporter 9 (GLUT9). URAT1 has been identified as a new member of the organic anion transporter family. Urate anion transporter 1: URAT1 (SLC22A12 gene), the major urate reabsorption transporter, was first identified in Xenopus oocytes. URAT1 is a protein with 12-transmembrane domains, including 555 amino acid residues. URAT1, specifically expressed at the side of the proximal tubular luminal membrane, is the key to maintain serum uric acid level by reabsorbing urate from the proximal tubule to the epithelia cells.  Some uric acid excretion agents such as probenecid, sulfinpyrazone and benzbromarone promote the excretion of uric acid by combining with URAT1 to interrupt the reabsorption of uric acid. Moreover, the angiotensin II receptor blocker losartan also increases the excretion of uric acid and lowers blood uric acid level by combining with URAT1.


1.Xu L,et al. Oncotarget. 2017 Nov 21; 8(59): 100852–100862.