Skip to main content
Advertisement

Main menu

  • Home
  • Articles
    • Current Issue
    • Fast Forward
    • Latest Articles
    • Special Sections
    • Archive
  • Information
    • Instructions to Authors
    • Submit a Manuscript
    • FAQs
    • For Subscribers
    • Terms & Conditions of Use
    • Permissions
  • Editorial Board
  • Alerts
    • Alerts
    • RSS Feeds
  • Virtual Issues
  • Feedback
  • Submit
  • Other Publications
    • Drug Metabolism and Disposition
    • Journal of Pharmacology and Experimental Therapeutics
    • Molecular Pharmacology
    • Pharmacological Reviews
    • Pharmacology Research & Perspectives
    • ASPET

User menu

  • My alerts
  • Log in
  • My Cart

Search

  • Advanced search
Journal of Pharmacology and Experimental Therapeutics
  • Other Publications
    • Drug Metabolism and Disposition
    • Journal of Pharmacology and Experimental Therapeutics
    • Molecular Pharmacology
    • Pharmacological Reviews
    • Pharmacology Research & Perspectives
    • ASPET
  • My alerts
  • Log in
  • My Cart
Journal of Pharmacology and Experimental Therapeutics

Advanced Search

  • Home
  • Articles
    • Current Issue
    • Fast Forward
    • Latest Articles
    • Special Sections
    • Archive
  • Information
    • Instructions to Authors
    • Submit a Manuscript
    • FAQs
    • For Subscribers
    • Terms & Conditions of Use
    • Permissions
  • Editorial Board
  • Alerts
    • Alerts
    • RSS Feeds
  • Virtual Issues
  • Feedback
  • Submit
  • Visit jpet on Facebook
  • Follow jpet on Twitter
  • Follow jpet on LinkedIn
Research ArticleABSORPTION, DISTRIBUTION, METABOLISM, AND EXCRETION

Effects of Age on In Vitro Midazolam Biotransformation in Male CD-1 Mouse Liver Microsomes

Jill S. Warrington, Joseph W. Poku, Lisa L. von Moltke, Richard I. Shader, Jerold S. Harmatz and David J. Greenblatt
Journal of Pharmacology and Experimental Therapeutics March 2000, 292 (3) 1024-1031;
Jill S. Warrington
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Joseph W. Poku
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Lisa L. von Moltke
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Richard I. Shader
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Jerold S. Harmatz
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
David J. Greenblatt
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • Article
  • Figures & Data
  • Info & Metrics
  • eLetters
  • PDF
Loading

Abstract

To study age-related changes in drug metabolism, we examined the in vitro biotransformation of midazolam (MDZ), a human cytochrome P-450 (CYP) 3A substrate, using liver microsomes from three age groups of male CD-1 mice ranging from 6 weeks to 2 years old. MDZ was metabolized to two major products, α-OH- and 4-OH-MDZ, which were quantified by HPLC. For both metabolites, Vmax values were reduced in old livers (P < .05), whileKm values did not change with age. The net intrinsic clearance (the sum ofVmax/Km for both pathways) also was reduced in the old animals (P < .05). The capacity of ketoconazole, a CYP3A inhibitor in humans, to inhibit the biotransformation of MDZ and of alprazolam, another human CYP3A substrate, did not differ significantly with age. At 100 μM alprazolam, 0.5μM ketoconazole inhibited metabolite formation by >80%. At 30 μM MDZ, 2.5 μM ketoconazole impaired 4-OH-MDZ formation by 88%, whereas it reduced α-OH-MDZ formation by only 46%. Immunoinhibition studies with polyclonal anti-rat CYP3A1/2 and CYP2C11 antibodies confirmed that 4-OH-MDZ formation was largely CYP3A-dependent, while α-OH-MDZ formation was mediated by CYP3A and -2C isoforms. Western blot analysis revealed decreased microsomal content of CYP3A in old livers. Net intrinsic clearance of MDZ was correlated with total CYP3A content (P < .001). These results demonstrate a reduction in MDZ biotransformation in old male mice, which may be attributable, in part, to decreased CYP3A content in old livers. Changes in expression and activity of CYP2C isoforms also may contribute to age-related changes in MDZ biotransformation, but this requires more investigation.

Footnotes

  • Send reprint requests to: Dr. David J. Greenblatt, Department of Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, 136 Harrison Ave., Boston, MA 02111. E-mail: DJ.Greenblatt{at}tufts.edu

  • ↵1 This work was funded, in part, by a grant from the John A. Hartford/AFAR Medical Students Geriatric Scholars Program and by Grants MH-34223, DA-05258, MH-19924, and RR-00054 from the Department of Health and Human Services. Dr. von Moltke is the recipient of a Scientist Development Award (K21-MH-01237) from the National Institutes of Mental Health.

  • Abbreviations:
    CYP
    cytochrome P-450
    MDZ
    midazolam
    ALP
    alprazolam
    • Received May 21, 1999.
    • Accepted November 18, 1999.
  • The American Society for Pharmacology and Experimental Therapeutics
View Full Text

JPET articles become freely available 12 months after publication, and remain freely available for 5 years. 

Non-open access articles that fall outside this five year window are available only to institutional subscribers and current ASPET members, or through the article purchase feature at the bottom of the page. 

 

  • Click here for information on institutional subscriptions.
  • Click here for information on individual ASPET membership.

 

Log in using your username and password

Forgot your user name or password?

Purchase access

You may purchase access to this article. This will require you to create an account if you don't already have one.
PreviousNext
Back to top

In this issue

Journal of Pharmacology and Experimental Therapeutics: 292 (3)
Journal of Pharmacology and Experimental Therapeutics
Vol. 292, Issue 3
1 Mar 2000
  • Table of Contents
  • About the Cover
  • Index by author
Download PDF
Article Alerts
Sign In to Email Alerts with your Email Address
Email Article

Thank you for sharing this Journal of Pharmacology and Experimental Therapeutics article.

NOTE: We request your email address only to inform the recipient that it was you who recommended this article, and that it is not junk mail. We do not retain these email addresses.

Enter multiple addresses on separate lines or separate them with commas.
Effects of Age on In Vitro Midazolam Biotransformation in Male CD-1 Mouse Liver Microsomes
(Your Name) has forwarded a page to you from Journal of Pharmacology and Experimental Therapeutics
(Your Name) thought you would be interested in this article in Journal of Pharmacology and Experimental Therapeutics.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Citation Tools
Research ArticleABSORPTION, DISTRIBUTION, METABOLISM, AND EXCRETION

Effects of Age on In Vitro Midazolam Biotransformation in Male CD-1 Mouse Liver Microsomes

Jill S. Warrington, Joseph W. Poku, Lisa L. von Moltke, Richard I. Shader, Jerold S. Harmatz and David J. Greenblatt
Journal of Pharmacology and Experimental Therapeutics March 1, 2000, 292 (3) 1024-1031;

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero

Share
Research ArticleABSORPTION, DISTRIBUTION, METABOLISM, AND EXCRETION

Effects of Age on In Vitro Midazolam Biotransformation in Male CD-1 Mouse Liver Microsomes

Jill S. Warrington, Joseph W. Poku, Lisa L. von Moltke, Richard I. Shader, Jerold S. Harmatz and David J. Greenblatt
Journal of Pharmacology and Experimental Therapeutics March 1, 2000, 292 (3) 1024-1031;
del.icio.us logo Digg logo Reddit logo Twitter logo Facebook logo Google logo Mendeley logo
  • Tweet Widget
  • Facebook Like
  • Google Plus One

Jump to section

  • Article
    • Abstract
    • Experimental Procedures
    • Results
    • Discussion
    • Footnotes
    • References
  • Figures & Data
  • Info & Metrics
  • eLetters
  • PDF

Related Articles

Cited By...

More in this TOC Section

  • Transport Is Not Rate-Limiting in Morphine Glucuronidation in the Single-Pass Perfused Rat Liver Preparation
  • Characterization of P-glycoprotein Inhibition by Major Cannabinoids from Marijuana
  • Enhanced Hepatic Uptake and Bioactivity of Type α1(I) Collagen Gene Promoter-Specific Triplex-Forming Oligonucleotides after Conjugation with Cholesterol
Show more ABSORPTION, DISTRIBUTION, METABOLISM, AND EXCRETION

Similar Articles

Advertisement
  • Home
  • Alerts
Facebook   Twitter   LinkedIn   RSS

Navigate

  • Current Issue
  • Fast Forward by date
  • Fast Forward by section
  • Latest Articles
  • Archive
  • Search for Articles
  • Feedback
  • ASPET

More Information

  • About JPET
  • Editorial Board
  • Instructions to Authors
  • Submit a Manuscript
  • Customized Alerts
  • RSS Feeds
  • Subscriptions
  • Permissions
  • Terms & Conditions of Use

ASPET's Other Journals

  • Drug Metabolism and Disposition
  • Molecular Pharmacology
  • Pharmacological Reviews
  • Pharmacology Research & Perspectives
ISSN 1521-0103 (Online)

Copyright © 2022 by the American Society for Pharmacology and Experimental Therapeutics