P-Glycoprotein Increases Portal Bioavailability of Loperamide in Mouse by Reducing First-Pass Intestinal Metabolism

@article{Dufek2013PGlycoproteinIP,
  title={P-Glycoprotein Increases Portal Bioavailability of Loperamide in Mouse by Reducing First-Pass Intestinal Metabolism},
  author={Matthew B. Dufek and Beverly Knight and Arlene S. Bridges and Dhiren R. Thakker},
  journal={Drug Metabolism and Disposition},
  year={2013},
  volume={41},
  pages={642 - 650}
}
P-glycoprotein (P-gp) and CYP3A (cytochrome P450 3A, generally; Cyp3a, rodent enzyme) in the intestine can attenuate absorption of orally administered drugs. While some suggest that P-gp enhances intestinal metabolism by CYP3A/Cyp3a during absorption of a dual substrate, others suggest that P-gp reduces the metabolism in the intestine when substrates are at subsaturating concentrations. Hence, to elucidate the cellular mechanisms that can address these divergent reports, we studied intestinal… 
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