Organic anion transporter (OAT) (OAT)

Organic anion transporters (OATs) are a subfamily of the solute carrier 22 (SLC22) family of membrane proteins, primarily expressed in the kidney, liver, and other barrier epithelia [1.1.1, 1.2.2]. They play a critical role in the systemic disposition and renal clearance of a wide range of endogenous metabolites, such as urate and prostaglandins, and exogenous substances, including many clinically important drugs like antibiotics, antivirals, and anti-inflammatory agents [1.2.3, 1.3.2]. OATs function as exchangers, typically coupling the uptake of organic anions into cells with the efflux of dicarboxylates like alpha-ketoglutarate [1.3.1, 1.4.1]. In the kidney, OAT1 and OAT3 are major uptake transporters on the basolateral membrane of proximal tubule cells, facilitating the first step of tubular secretion [1.3.1, 1.4.2]. Because of their broad substrate specificity, OATs are frequent sites of drug-drug interactions and are involved in the pathogenesis of drug-induced nephrotoxicity [1.2.1, 1.4.4]. They are also therapeutic targets; for instance, inhibitors like probenecid are used to modulate drug half-lives or treat hyperuricemia by inhibiting urate reabsorption via URAT1 [1.3.1, 1.3.2].

Other names

SLC22 familySolute carrier family 22OATsMultispecific organic anion transportersOrganic anion transporter 1 (OAT1)Organic anion transporter 3 (OAT3)Urate transporter 1 (URAT1)Novel kidney transporter (NKT)SLC22A6SLC22A8SLC22A12

Organic anion transporters (OATs) primarily function as tertiary active transporters that exchange intracellular dicarboxylates (such as alpha-ketoglutarate) for extracellular organic anions [1.3.1, 1.4.1]. Drugs targeting these transporters typically act as competitive inhibitors to either reduce the renal clearance of co-administered drugs (thereby increasing their plasma concentration and half-life) or to block the reabsorption of endogenous substances like uric acid in the proximal tubule to treat conditions such as gout [1.3.1, 1.3.2].