English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We have shown that the rat can quantitatively predict the verapamil-cyclopsorine A (CsA) drug-drug interaction (DDI) at the human blood-brain barrier (BBB). In addition, the potency (EC(50)) of CsA to inhibit rat BBB P-gp can be predicted from in vitro studies in MDRI-transfected cells. To assess if these excellent agreements extend to other substrates, we determined the magnitude of P-gp-based DDI at the rat BBB between loperamide (Lop) or its metabolite, N-desmethyl Lop (dLop), and escalating CsA blood concentrations. The percent increase in the brain:blood Lop concentration ratio was described by the Hill equation, E(max) = 2000%, EC(50) = 7.1 μM and γ = 3.7. The potency (EC(50)) of CsA to inhibit P-gp at the rat BBB was independent of the substrate used (verapamil, Lop, or dLop). Like the verapamil-CsA DDI, the potency (EC(50)) of CsA to inhibit rat BBB P-gp could be predicted from studies in MDRI-transfected cells. When (11)C-Lop was coadministered with a 10 mg/kg iv infusion of CsA (1) yielding ~5.6 uM CsA blood concentration to healthy volunteers, the brain distribution of (11)C-radioactivity was increased by 110%. (1) When corrected for diffusible Lop metabolite(s), this translates into an increase in (11)C-Lop brain distribution of 457%. Based on our rat data, we estimated a similar value at 5.6 μM blood CsA concentration, 588% increase in Lop brain distribution. These data support our conclusion that the rat is a promising model to predict P-gp based DDI at the human BBB.

molecular pharmaceutics

P-Glycoprotein-Based Loperamide–Cyclosporine Drug Interaction at the Rat Blood–Brain Barrier: Prediction from <i>In Vitro</i> Studies and Extrapolation to Humans

P-Glycoprotein-Based Loperamide–Cyclosporine Drug Interaction at the Rat Blood–Brain Barrier: Prediction from In Vitro Studies and Extrapolation to Humans