Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Endotoxin increases hepatic glutamine transport activity

Y Inoue1, A J Pacitti, W W Souba

  • 1Department of Surgery, University of Florida, Gainesville 32610-0286.

The Journal of Surgical Research
|May 1, 1993
PubMed
Summary

Sepsis accelerates liver glutamine uptake by increasing the activity of the Na(+)-dependent System N transporter in hepatocytes. This enhanced transport mechanism is crucial for managing elevated hepatic glutamine during severe infections.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Outcomes in a series of 103 retroperitoneal sarcomas.

European journal of surgical oncology : the journal of the European Society of Surgical Oncology and the British Association of Surgical Oncology·2006
Same author

Mechanisms governing the expression of the enzymes of glutamine metabolism--glutaminase and glutamine synthetase.

The Journal of nutrition·2001
Same author

Glutamine metabolism in sepsis and infection.

The Journal of nutrition·2001
Same author

Political strategy, business strategy, and the academic medical center: linking theory and practice.

The Journal of surgical research·2001
Same author

The effect of surgical site infections on outcomes and resource utilization after liver transplantation.

Surgery·2001
Same author

Asparagine uptake in rat hepatocytes: resolution of a paradox and insights into substrate-dependent transporter regulation.

Amino acids·2001

Area of Science:

  • Hepatology
  • Molecular Physiology
  • Sepsis Pathophysiology

Background:

  • Liver glutamine uptake increases during endotoxemia (a model of sepsis).
  • The specific plasma membrane transport systems responsible for this altered uptake remain largely uncharacterized.
  • Understanding these transporters is key to comprehending hepatic metabolic responses during sepsis.

Purpose of the Study:

  • To investigate the impact of sepsis on hepatic glutamine transport systems.
  • To determine if increased hepatocyte plasma membrane transport activity underlies accelerated liver glutamine uptake during endotoxemia.
  • To characterize the roles of Na(+)-dependent System N and Na(+)-independent System n transporters.

Main Methods:

  • Preparation of rat hepatocyte plasma membrane vesicles (HPMVs) from control and lipopolysaccharide (LPS)-treated rats.

Related Experiment Videos

  • Assay of [3H]glutamine transport in HPMVs using a rapid mixing/filtration technique.
  • Measurement of Na(+)-dependent (System N) and Na(+)-independent (System n) transport activities, Vmax, and Km.

    • Main Results:

    • Na(+)-independent glutamine transport (System n) activity remained unchanged after LPS administration.
    • A time- and dose-dependent 2- to 3-fold increase in Na(+)-dependent glutamine transport (System N) was observed in HPMVs from endotoxemic rats.
    • This increase was attributed to a higher Vmax, indicating more transporter proteins, while glutamine affinity (Km) was unaffected.

    Conclusions:

    • Endotoxemia significantly enhances the activity of the Na(+)-dependent glutamine transporter (System N) in the hepatocyte plasma membrane.
    • This upregulation of System N activity is a primary mechanism driving accelerated hepatic glutamine uptake during severe infection.
    • The findings provide critical insights into the metabolic adaptations of the liver during sepsis.