title: Effect of probenecid on the biliary excretion of belotecan.
abstract: The purpose of this study was to investigate the effect of probenecid, an inhibitor of the MRP2/ ABCC transporter, on the pharmacokinetics and transport of belotecan (7-[2-(N-isopropylamino)ethyl]-(20S)-camptothecin). The effect of probenecid on the pharmacokinetics of belotecan was studied in rats. When belotecan was injected as a bolus dose of 5 mg/kg after probenecid was infused at a rate of 42.8 mg/2 mL/h/kg, the cumulative biliary excretion amounts and biliary clearance (CL(b)) of belotecan decreased (28.29 +/- 2.83 versus 19.96 +/- 1.45% of dose and 161.01 +/- 26.95 versus 92.66 +/- 1.45 mL/min/kg), whereas the systemic pharmacokinetics did not change. This indicates that the MRP2 transporter is involved in the biliary excretion of belotecan. The involvement of MRP2 in the secretory transport was further characterized using Caco-2 cell monolayers expressing MRP2. The apparent permeability across Caco-2 cell monolayers from basolateral to apical was 2.3 times greater than that from the apical to the basolateral side at the 50 microM belotecan. In addition, probenecid significantly decreased the basolateral-to-apical transport of belotecan (52.9%). These results indicate that MRP2 is involved in the secretory transport of belotecan in biliary excretion.
authors: Research Institute of Pharmaceutical Sciences & Department of Pharmaceutics, College of Pharmacy, Seoul National University, Seoul 151-742, Korea.
authors: Eun-Mi
authors: EM
authors: Namkoong
authors: In-Wha
authors: IW
authors: Kim
authors: Dae-Duk
authors: DD
authors: Kim
authors: Suk-Jae
authors: SJ
authors: Chung
authors: Chang-Koo
authors: CK
authors: Shim
mesh_terms: D000818:Animals; D001646:Bile / Q000378:metabolism*; D001692:Biological Transport; D018938:Caco-2 Cells; D002166:Camptothecin / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D006801:Humans; D008297:Male; D026901:Membrane Transport Proteins / Q000502:physiology*; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000037:antagonists & inhibitors / Q000502:physiology*; D011339:Probenecid / Q000494:pharmacology*; D051381:Rats
chemical_list: D002166:Camptothecin; D026901:Membrane Transport Proteins; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D011339:Probenecid; C000715087:ABCC2 protein, human; C116963:belotecan