Organic cation transporter 1 (OCT1)

Organic cation transporter 1 (OCT1) is a polyspecific membrane transporter encoded by SLC22A1 and primarily expressed in the liver, where it facilitates the uptake of a wide range of endogenous and exogenous organic cations from the blood into hepatocytes as the first step in hepatic drug elimination[1][3][4][6]. OCT1 is electrogenic, Na+-independent, and demonstrates broad substrate selectivity, transporting many drugs such as metformin and endogenous compounds like choline[1][4]. It has a critical role in determining drug bioavailability and disposition and exhibits significant inter-individual and interspecies variability in both expression and activity. Polymorphisms in SLC22A1 can impact therapeutic efficacy and toxicity of drugs, most notably metformin in type 2 diabetes[7]. OCT1 can also be found, at lower levels, in the intestine, kidney, and other tissues[1][2]. It is a well-established therapeutic, pharmacokinetic, and toxicity-modifying target in clinical pharmacology.

Other names

Solute carrier family 22 member 1SLC22A1Orct1organic cation transporter protein 1

Uptake and clearance of drugs and toxins from blood via facilitative, Na+-independent transport; Modulation of hepatic drug bioavailability; Polyspecific transport and possible competitive inhibition or substrate competition