Organic anion transporting polypeptide 1B (OATP1B)

The Organic anion transporting polypeptide 1B (OATP1B) subfamily, primarily consisting of OATP1B1 and OATP1B3, represents a critical group of uptake transporters located on the sinusoidal (basolateral) membrane of human hepatocytes [2, 4]. These transporters are essential for the hepatic clearance of a wide variety of endogenous substances, including bilirubin, bile acids, and thyroid hormones, as well as numerous clinically significant drugs [5, 7]. OATP1B transporters are major determinants of the pharmacokinetics of many drugs, most notably the HMG-CoA reductase inhibitors (statins), and their inhibition by co-administered medications can lead to profound drug-drug interactions and increased risk of systemic toxicities such as myopathy [6, 11]. Genetic variations in the genes encoding these transporters, particularly the SLCO1B1*5 polymorphism, are well-known to cause significant inter-individual variability in drug exposure and adverse effect profiles [1, 14]. Beyond their physiological role in the liver, OATP1B members are frequently overexpressed in various cancers, where they may influence the intracellular accumulation and efficacy of chemotherapeutic agents [1, 10].

Other names

SLCO1BOATP1B1OATP1B3Solute carrier organic anion transporter family member 1BOATP-COATP-8LST-1LST-2OATP2

Facilitated, sodium-independent uptake of organic anions from the blood across the sinusoidal (basolateral) membrane into hepatocytes [2, 5, 6].