Go to JCI Insight
  • About
  • Editors
  • Consulting Editors
  • For authors
  • Publication ethics
  • Alerts
  • Advertising
  • Job board
  • 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 ...
    • Immune Environment in Glioblastoma (Upcoming)
    • Korsmeyer Award 25th Anniversary Collection (Jan 2023)
    • Aging (Jul 2022)
    • Next-Generation Sequencing in Medicine (Jun 2022)
    • New Therapeutic Targets in Cardiovascular Diseases (Mar 2022)
    • Immunometabolism (Jan 2022)
    • Circadian Rhythm (Oct 2021)
    • View all review series ...
  • Viewpoint
  • Collections
    • In-Press Preview
    • Commentaries
    • Research letters
    • Letters to the editor
    • 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
  • In-Press Preview
  • Commentaries
  • Research letters
  • Letters to the editor
  • Editorials
  • Viewpoint
  • Top read articles
  • About
  • Editors
  • Consulting Editors
  • For authors
  • Publication ethics
  • Alerts
  • Advertising
  • Job board
  • Subscribe
  • Contact
Top
  • View PDF
  • Download citation information
  • Send a comment
  • Share this article
  • Terms of use
  • Standard abbreviations
  • Need help? Email the journal
  • Top
  • Abstract
  • Version history
  • Article usage
  • Citations to this article

Advertisement

Amendment history:
  • Correction (April 1993)

Research Article Free access | 10.1172/JCI116030

Microfilament-dependent activation of Na+/K+/2Cl- cotransport by cAMP in intestinal epithelial monolayers.

J B Matthews, C S Awtrey, and J L Madara

Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts.

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

Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts.

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

Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts.

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

Published October 1, 1992 - More info

Published in Volume 90, Issue 4 on October 1, 1992
J Clin Invest. 1992;90(4):1608–1613. https://doi.org/10.1172/JCI116030.
© 1992 The American Society for Clinical Investigation
Published October 1, 1992 - Version history
View PDF
Abstract

cAMP-mediated stimulation of Cl- secretion in the human intestinal cell line T84 is accompanied by significant remodeling of F-actin, and both the secretory and cytoskeletal responses may be largely ablated by previous cell loading with phalloidin derivatives, reagents that prevent dynamic reordering of microfilaments (1991. J. Clin. Invest. 87:1903-1909). In this study, we examined the effect of phalloidin loading on the cAMP-elicited activity of the individual membrane-associated transport proteins involved in electrogenic Cl- secretion. Efflux of 125I and 86Rb was used to assay forskolin-stimulated Cl- and K+ conductances, respectively, and no inhibitory effect of phalloidin could be detected. Na+/K(+)-ATPase pump activity, assessed as bumetanide-insensitive 86Rb uptake and the ability of monolayers to generate a Na+ absorptive current in response to apical addition of a Na+ ionophore, was not different between control and phalloidin-loaded monolayers. Forskolin was found to stimulate Na+/K+/2Cl- cotransport (bumetanide-sensitive 86Rb uptake) in time-dependent fashion. In the absence of any agonist, cotransporter activity was markedly decreased in phalloidin-loaded monolayers. Furthermore, under phalloidin-loaded conditions, the forskolin-elicited increase in bumetanide-sensitive 86Rb uptake was markedly attenuated. These findings suggest that cAMP-induced activity of Cl- channels, K+ channels, and the Na+/K(+)-ATPase are not influenced by F-actin stabilization. However, cAMP-induced activation of the Na+/K+/2Cl- cotransporter appears to be microfilament-dependent, and ablation of this event is likely to account for the inhibition of cAMP-elicited Cl- secretion seen in the phalloidin-loaded state. Such findings suggest that Na+/K+/2Cl- cotransporter is functionally linked to the cytoskeleton and is a regulated site of cAMP-elicited electrogenic Cl- secretion.

Images.

Browse pages

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

icon of scanned page 1608
page 1608
icon of scanned page 1609
page 1609
icon of scanned page 1610
page 1610
icon of scanned page 1611
page 1611
icon of scanned page 1612
page 1612
icon of scanned page 1613
page 1613
Version history
  • Version 1 (October 1, 1992): No description

Article tools

  • View PDF
  • Download citation information
  • Send a comment
  • Share this article
  • Terms of use
  • Standard abbreviations
  • Need help? Email the journal

Metrics

  • Article usage
  • Citations to this article

Go to

  • Top
  • Abstract
  • Version history
Advertisement
Advertisement

Copyright © 2023 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)

Sign up for email alerts