Organic anion transporters 1 and 3 (SLC22A6 / SLC22A8)
Also known as: OAT1, OAT3, SLC22A6, SLC22A8, ROAT1, ROAT3
Uptake transporters (SLC22A6/SLC22A8) expressed in the proximal renal tubules, responsible for tubular secretion of organic anions and anionic drugs such as antivirals (tenofovir, aciclovir), NSAIDs, loop diuretics and penicillins.
OAT1/OAT3 inhibition (e.g. probenecid, NSAIDs, cotrimoxazole) reduces tubular secretion of substrates and raises plasma concentrations; probenecid is intentionally used to prolong penicillin action.
Probenecid is clinically used to prolong penicillin half-life (blocking tubular secretion); NSAIDs can raise methotrexate and tenofovir levels by OAT inhibition.