Human organic anion transporter (OAT (collective for Organic Anion Transporters; specific members include OAT1/SLC22A6, OAT2/SLC22A7, OAT3/SLC22A8, etc.))

Human organic anion transporters (OATs) are a family of solute carrier membrane proteins (notably SLC22A family, including OAT1/SLC22A6, OAT2/SLC22A7, OAT3/SLC22A8) that play a central role in the renal and hepatic transport of a broad spectrum of endogenous organic anions and drugs. These transporters are crucial for the elimination of waste products, xenobiotics, and a wide range of pharmaceuticals. They are highly expressed in the basolateral membrane of kidney proximal tubule cells (also in liver and other tissues) and facilitate the vectorial movement of substrates from bloodstream into tubular or hepatocellular cells in exchange for dicarboxylates. Their function underpins many pharmacokinetic drug–drug interactions and their dysfunction or inhibition can lead to disease-related toxin accumulation and altered drug exposure. OATs are well-established therapeutic and off-targets for a wide range of drugs and represent key determinants of drug safety and efficacy in clinical settings[1][2][3][4][5][6][7].

Other names

Organic anion transporterOATSolute carrier family 22 member (SLC22A) transporterOrganic anion transporting polypeptide (sometimes non-preferred for OAT vs OATP)SLC22A family

Inhibitors block the transporter, decreasing renal (or hepatic) clearance of substrates and raising their systemic exposure. Substrates are eliminated by vectorial transport from blood to urine (in kidney) or from blood to bile (in liver). Exchanges organic anions for intracellular dicarboxylates via tertiary active transport, often Na+-independent but reliant on sodium gradient for dicarboxylate return[1][3][4].