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Updated: Apr 23, 2026
06:43
Functional Assessment of Intestinal Tight Junction Barrier and Ion Permeability in Native Tissue by Ussing Chamber Technique
Published on: May 26, 2021
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Tight junction, selective permeability, and related diseases.
Susanne M Krug1, Jörg D Schulzke1, Michael Fromm1
1Institute of Clinical Physiology, Campus Benjamin Franklin, Charité - Universitätsmedizin Berlin, 12203 Berlin, Germany.
Seminars in Cell & Developmental Biology
|September 16, 2014
Summary
Tight junction proteins form selective channels and barriers, influencing what passes between cells. Dysregulation of these proteins can cause diseases by altering paracellular transport.
Area of Science:
- Cell biology
- Molecular biology
- Physiology
Background:
- Tight junctions form selective barriers between cells.
- Some tight junction proteins form channels, while others act as barriers.
- These proteins exhibit selectivity for ions, water, or macromolecules.
Purpose of the Study:
- To review the properties of tight junction proteins.
- To explain how selective permeability of these proteins contributes to diseases.
- To highlight the role of tight junctions in paracellular transport.
Main Methods:
- Literature review of tight junction protein functions.
- Analysis of protein selectivity mechanisms (cation, anion, water).
- Correlation of protein dysregulation with disease pathogenesis.
Main Results:
- Tight junction proteins display diverse selectivity, including cation, anion, and water channels.
- Barrier-forming claudins can also be charge-selective.
- Occludin and tricellulin are crucial for blocking large molecules.
Conclusions:
- Altered tight junction permeability due to protein defects leads to diseases.
- Examples include kidney magnesium loss, intestinal diarrhea, and pathogen uptake.
- Understanding selective permeability is key to addressing tight junction-related diseases.
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