Estimation of transporters involved in the hepatobiliary transport of TA-0201CA using sandwich-cultured rat hepatocytes from normal and multidrug resistance-associated protein 2-deficient rats

Drug Metab Dispos. 2010 Sep;38(9):1505-13. doi: 10.1124/dmd.110.033258. Epub 2010 Jun 10.

Abstract

N-[6-[2-[(5-Bromo-2-pyrimidinyl)oxy]ethoxy]-5-(4-methylphenyl)-4-pyrimidinyl]-4-(2-hydroxy-1,1-dimethylethyl) benzenesulfonamide sodium salt (TA-0201) carboxylic acid form (TA-0201CA) is the primary and pharmacologically active metabolite of TA-0201, which is an orally active nonpeptide antagonist for endothelin receptors. A major elimination route of TA-0201CA in rats was biliary excretion. The aim of this study was to clarify the transporters responsible for the hepatobiliary transport of TA-0201CA by in vivo pharmacokinetic study and in vitro study using sandwich-cultured rat hepatocytes (SCRH) from normal rats [Sprague-Dawley rats (SDR)] and Eisai hyperbilirubinemic rats (EHBR). After intravenous administration, TA-0201CA was extensively excreted into bile with a high biliary clearance in SDR. In contrast, the biliary clearance in EHBR was lower than that in SDR. These results indicated that multidrug resistance-associated protein 2 (Mrp2) was partly involved in the biliary excretion of TA-0201CA. In SCRH, the hepatic uptake of TA-0201CA was significantly decreased by the presence of organic anion-transporting polypeptide (Oatp) substrates/inhibitors and a Na(+)-free condition, which is a driving force of the Na(+)-taurocholate cotransporting polypeptide (Ntcp). The canalicular secretion of TA-0201CA was inhibited by the bile salt export pump (Bsep) inhibitor glibenclamide and by the Mrp2 inhibitor 3-[[3-[2-(7-chloroquinolin-2-yl)vinyl]phenyl]-(2-dimethylcarbamoylethylsulfanyl)methylsulfanyl] propionic acid (MK-571) in SCRH from SDR and EHBR. These results suggested that TA-0201CA was transported into hepatocytes via Oatps and Ntcp and excreted into bile via Mrp2 and Bsep in rats.

MeSH terms

  • Animals
  • Biliary Tract / metabolism*
  • Endothelin Receptor Antagonists*
  • Hepatocytes / metabolism*
  • Liver / metabolism*
  • Male
  • Pyrimidines / blood
  • Pyrimidines / pharmacokinetics*
  • Rats
  • Sulfonamides / blood
  • Sulfonamides / pharmacokinetics*

Substances

  • Endothelin Receptor Antagonists
  • Pyrimidines
  • Sulfonamides
  • T 0201