Pflügers Archiv

, Volume 447, Issue 5, pp 666–676

The SLC22 drug transporter family

The ABC of Solute Carriers Guest Editor: Matthias A. Hediger

DOI: 10.1007/s00424-003-1089-9

Cite this article as:
Koepsell, H. & Endou, H. Pflugers Arch - Eur J Physiol (2004) 447: 666. doi:10.1007/s00424-003-1089-9


The SLC22 family comprises organic cation transporters (OCTs), zwitterion/cation transporters (OCTNs), and organic anion transporters (OATs). These transporters contain 12 predicted α-helical transmembrane domains (TMDs) and one large extracellular loop between TMDs 1 and 2. Transporters of the SLC22 family function in different ways: (1) as uniporters that mediate facilitated diffusion in either direction (OCTs), (2) as anion exchangers (OAT1, OAT3 and URAT1), and (3) as Na+/l-carnitine cotransporter (OCTN2). They participate in the absorption and/or excretion of drugs, xenobiotics, and endogenous compounds in intestine, liver and/or kidney, and perform homeostatic functions in brain and heart. The endogenous substrates include monoamine neurotransmitters, choline, l-carnitine, α-ketoglutarate, cAMP, cGMP, prostaglandins, and urate. Defect mutations of transporters of the SLC22 family may cause specific diseases such as "primary systemic carnitine deficiency" or "idiopathic renal hypouricemia" or change drug absorption or excretion.


Carnitine transporterDrug transportersExcretionOrganic anionsOrganic cationsPolyspecific transportersUrate transporter

Copyright information

© Springer-Verlag  2004

Authors and Affiliations

  1. 1.Institute of Anatomy and Cell BiologyBayerische Maximilians Universität WürzburgWürzburgGermany
  2. 2.Department of Pharmacology and ToxicologyKyorin University School of MedicineTokyoJapan