PT - JOURNAL ARTICLE AU - Hirano, Masaru AU - Maeda, Kazuya AU - Hayashi, Hisamitsu AU - Kusuhara, Hiroyuki AU - Sugiyama, Yuichi TI - Bile Salt Export Pump (BSEP/ABCB11) Can Transport a Nonbile Acid Substrate, Pravastatin AID - 10.1124/jpet.105.084830 DP - 2005 Aug 01 TA - Journal of Pharmacology and Experimental Therapeutics PG - 876--882 VI - 314 IP - 2 4099 - http://jpet.aspetjournals.org/content/314/2/876.short 4100 - http://jpet.aspetjournals.org/content/314/2/876.full SO - J Pharmacol Exp Ther2005 Aug 01; 314 AB - Pravastatin is a well known 3-hydroxy-3-methylglutaryl-CoA reductase inhibitor. Cumulative studies have shown that pravastatin is taken up into hepatocytes by the organic anion transporting polypeptide family transporters and excreted into the bile as an intact form by multidrug resistance-associated protein 2 (MRP2). It is generally accepted that the bile salt export pump (BSEP/ABCB11) mainly transports bile acids and plays an indispensable role in their biliary excretion. Interestingly, we found that BSEP could accept pravastatin as a substrate. Significant ATP-dependent uptake of pravastatin by human BSEP (hBSEP)- and rat BSEP (rBsep)-expressing membrane vesicles was observed, and the ratio of the uptake activity of pravastatin to that of taurocholic acid (TCA) by hBSEP was 3.3-fold higher than that by rBsep. The Km value of pravastatin for hBSEP was 124 μM. A mutual inhibition study between TCA and pravastatin revealed that they competitively interact with hBSEP. Several statins inhibited the hBSEP- and rBsep-mediated uptake of TCA; however, the specific uptake of other statins (cerivastatin, fluvastatin, and pitavastatin) by hBSEP and rBSEP was not detected. The inhibitory effects of hydrophilic statins (pravastatin and rosuvastatin) on the uptake of TCA by BSEP were relatively lower than those of lipophilic statins. These data suggest that BSEP may be partly involved in the biliary excretion of pravastatin in both rats and humans. The American Society for Pharmacology and Experimental Therapeutics