Abstract
One of the most prevalent and interfering psychosocial comorbidities of HIV infection is clinical depression (22 to 45%). For this reason, a study of a possible interaction between the nonnucleoside reverse transcriptase inhibitor nevirapine (NVP) and the tricyclic antidepressant nortriptyline (NT) was carried out. In vitro studies with rat and human hepatic microsomes showed a marked inhibition of NVP metabolism by NT being more intense in rat than in human. The extrapolation of these results to humans suggests increased NVP side effects when both drugs are coadministered, but additional in vivo human studies are required to evaluate the clinical implication of this interaction.This protocol describes a technique for detecting and measuring the inhibition of the nevirapine metabolism by nortriptyline in hepatic microsomes.
Keywords: Nevirapine, Nortriptyline, Metabolism inhibition, Drug interaction, Hepatic microsomes
Materials and Reagents
Equipment
Procedure
Representative data
Figure 1. Representative HPLC-UV chromatogram of NVP metabolism in rat liver microsomes (NVP 5 µg/ml). A. Standard of NVP (no metabolism); B. NVP after 30 min at 37 °C; C. NVP and NT (10 µg/ml) after 30 min at 37 °C. Figure 2. Representative HPLC-UV chromatogram of NVP metabolism in human liver microsomes (NVP 5 µg/ml). A. Standard of NVP (no metabolism); B. NVP after 30 min at 37 °C; C. NVP and NT (10 µg/ml) after 30 min at 37 °C.
Notes
Solutions and materials used for the isolation of rat microsomes have to be kept on ice (4 °C).
Recipes
Acknowledgments
This protocol was recently described and applied by Usach et al. (2014). Isolation of rat microsomes and composition of mediums used in the inhibition assay were adapted from Kawashima et al. (1999) and Choi et al. (2008), respectively. Extraction of NVP and its metabolites from human microsomes was adapted from Erickson et al. (1999). I. Usach has been granted a predoctoral fellowship from the Atracció de Talent (VLC-CAMPUS) program of University of Valencia.
References
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