Go to JCI Insight
  • About
  • Editors
  • Consulting Editors
  • For authors
  • Alerts
  • Advertising/recruitment
  • Subscribe
  • Contact
  • Current Issue
  • Past Issues
  • By specialty
    • COVID-19
    • Cardiology
    • Gastroenterology
    • Immunology
    • Metabolism
    • Nephrology
    • Neuroscience
    • Oncology
    • Pulmonology
    • Vascular biology
    • All ...
  • Videos
    • Conversations with Giants in Medicine
    • Author's Takes
  • Reviews
    • View all reviews ...
    • 100th Anniversary of Insulin's Discovery (Jan 2021)
    • Hypoxia-inducible factors in disease pathophysiology and therapeutics (Oct 2020)
    • Latency in Infectious Disease (Jul 2020)
    • Immunotherapy in Hematological Cancers (Apr 2020)
    • Big Data's Future in Medicine (Feb 2020)
    • Mechanisms Underlying the Metabolic Syndrome (Oct 2019)
    • Reparative Immunology (Jul 2019)
    • View all review series ...
  • Viewpoint
  • Collections
    • Recently published
    • In-Press Preview
    • Commentaries
    • Concise Communication
    • Editorials
    • Viewpoint
    • Top read articles
  • Clinical Medicine
  • JCI This Month
    • Current issue
    • Past issues

  • Current issue
  • Past issues
  • Specialties
  • Reviews
  • Review series
  • Conversations with Giants in Medicine
  • Author's Takes
  • Recently published
  • In-Press Preview
  • Commentaries
  • Concise Communication
  • Editorials
  • Viewpoint
  • Top read articles
  • About
  • Editors
  • Consulting Editors
  • For authors
  • Alerts
  • Advertising/recruitment
  • Subscribe
  • Contact
Top
  • View PDF
  • Download citation information
  • Send a letter
  • Share this article
  • Terms of use
  • Standard abbreviations
  • Need Help? E-mail the JCI
  • Top
  • Abstract
  • Version history
  • Article usage
  • Citations to this article

Advertisement

Research Article Free access | 10.1172/JCI116064

Identification of rifampin-inducible P450IIIA4 (CYP3A4) in human small bowel enterocytes.

J C Kolars, P Schmiedlin-Ren, J D Schuetz, C Fang, and P B Watkins

Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor.

Find articles by Kolars, J. in: JCI | PubMed | Google Scholar

Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor.

Find articles by Schmiedlin-Ren, P. in: JCI | PubMed | Google Scholar

Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor.

Find articles by Schuetz, J. in: JCI | PubMed | Google Scholar

Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor.

Find articles by Fang, C. in: JCI | PubMed | Google Scholar

Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor.

Find articles by Watkins, P. in: JCI | PubMed | Google Scholar

Published November 1, 1992 - More info

Published in Volume 90, Issue 5 on November 1, 1992
J Clin Invest. 1992;90(5):1871–1878. https://doi.org/10.1172/JCI116064.
© 1992 The American Society for Clinical Investigation
Published November 1, 1992 - Version history
View PDF
Abstract

Enzymes within the P450IIIA (CYP3A) subfamily appear to account for significant "first pass" metabolism of some drugs in the intestine. To identify which of the known P450IIIA genes are expressed in intestine, enterocyte RNA was hybridized on Northern blots with synthetic oligonucleotides complementary to hypervariable regions of hepatic P450IIIA4, P450IIIA5, and P450IIIA7 cDNAs. Hybridization was detected only with the P450IIIA4-specific oligonucleotide. The identity of the hybridizing mRNA was confirmed to be P450IIIA4 by direct sequencing of a DNA fragment amplified from enterocyte cDNA by the polymerase chain reaction. To determine if enterocyte P450IIIA4 is inducible, biopsies of small bowel mucosa were obtained from five volunteers before and after they received 7d of treatment with rifampin, a known inducer of P450IIIA4 in liver. Rifampin treatment resulted in a five- or eightfold mean increase (P < 0.05) in the biopsy concentration of P450IIIA4 mRNA when normalized for content of sucrase isomaltase or intestinal fatty acid binding protein mRNAs, respectively. Rifampin also induced P450IIIA immunoreactive protein in enterocytes in each of the subjects, as judged by immunohistochemistry, and resulted in a 10-fold increase in P450IIIA4-specific catalytic activity (erythromycin N-demethylation) in the one patient studied. Our identification of inducible P450IIIA4 in enterocytes may in part account for drug interactions characteristic of P450IIIA4 substrates and suggests a strategy for controlling entry into the body of a major class of xenobiotics.

Images.

Browse pages

Click on an image below to see the page. View PDF of the complete article

icon of scanned page 1871
page 1871
icon of scanned page 1872
page 1872
icon of scanned page 1873
page 1873
icon of scanned page 1874
page 1874
icon of scanned page 1875
page 1875
icon of scanned page 1876
page 1876
icon of scanned page 1877
page 1877
icon of scanned page 1878
page 1878
Version history
  • Version 1 (November 1, 1992): No description

Article tools

  • View PDF
  • Download citation information
  • Send a letter
  • Share this article
  • Terms of use
  • Standard abbreviations
  • Need Help? E-mail the JCI

Metrics

  • Article usage
  • Citations to this article

Go to

  • Top
  • Abstract
  • Version history
Advertisement
Advertisement
Follow JCI:
Copyright © 2021 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)

Sign up for email alerts