Drug- and estrogen-induced cholestasis through inhibition of the hepatocellular bile salt export pump (Bsep) of rat liver.

Article Details

Citation

Stieger B, Fattinger K, Madon J, Kullak-Ublick GA, Meier PJ

Drug- and estrogen-induced cholestasis through inhibition of the hepatocellular bile salt export pump (Bsep) of rat liver.

Gastroenterology. 2000 Feb;118(2):422-30.

PubMed ID
10648470 [ View in PubMed
]
Abstract

BACKGROUND & AIMS: Drug-induced cholestasis is a frequent form of acquired liver disease. To elucidate the molecular pathogenesis of drug-induced cholestasis, we investigated the effects of prototypic cholestatic drugs on the canalicular bile salt export pump (Bsep) of rat liver. METHODS: Vesicles were isolated from Bsep-, Mrp2-, and Bsep/Mrp2-expressing Sf9 cells. Canalicular plasma membrane (cLPM) vesicles from rat liver and Sf9 cell vesicles were used to study adenosine triphosphate (ATP)-dependent solute uptake by a rapid filtration technique. RESULTS: Bsep-expressing Sf9 cell vesicles showed ATP-dependent transport of numerous monoanionic bile salts with similar Michaelis constant values as in cLPM vesicles, whereas several known substrates of the multispecific organic anion transporter Mrp2 were not transported by Bsep. Cyclosporin A, rifamycin SV, rifampicin, and glibenclamide cis-inhibited Bsep-mediated bile salt transport to similar extents as ATP-dependent taurocholate transport in cLPM vesicles. In contrast, the cholestatic estrogen metabolite estradiol-17beta-glucuronide inhibited ATP-dependent taurocholate transport only in normal cLPM and in Bsep/Mrp2-coexpressing Sf9 cell vesicles, but not in Mrp2-deficient cLPM or in selectively Bsep-expressing Sf9 cell vesicles, indicating that it trans-inhibits Bsep only after its secretion into bile canaliculi by Mrp2. CONCLUSIONS: These results provide a molecular basis for previous in vivo observations and identify Bsep as an important target for induction of drug- and estrogen-induced cholestasis in mammalian liver.

DrugBank Data that Cites this Article

Drug Transporters
DrugTransporterKindOrganismPharmacological ActionActions
CyclosporineBile salt export pumpProteinHumans
Unknown
Substrate
Inhibitor
Details
EthinylestradiolBile salt export pumpProteinHumans
Unknown
Inhibitor
Details
GlutathioneCanalicular multispecific organic anion transporter 1ProteinHumans
Unknown
Substrate
Inhibitor
Details
GlyburideBile salt export pumpProteinHumans
Unknown
Substrate
Inhibitor
Details
Glycochenodeoxycholic AcidBile salt export pumpProteinHumans
Unknown
Substrate
Inhibitor
Details
RifampicinBile salt export pumpProteinHumans
Unknown
Inhibitor
Details