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Updated: Jun 19, 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
CONDUCTIVITY AND PERMEABILITY.
1Laboratory of Plant Physiology, Harvard University, Cambridge.
The Journal of General Physiology
|October 30, 2009
Summary
Electrical current in plants splits between cell walls and protoplasm. Calculations confirm that whole tissue resistance studies accurately reflect protoplasm resistance and ion permeability.
Area of Science:
- Plant physiology
- Biophysics
Background:
- Electrical current flow in plant tissues involves both cell walls and protoplasm.
- Understanding ion transport is crucial for plant cell function.
Purpose of the Study:
- To calculate the distribution of electrical current between plant cell walls and protoplasm.
- To determine if whole tissue resistance studies reflect protoplasm properties.
Main Methods:
- Electrical measurements of plant tissue resistance.
- Calculations to partition current flow through cell walls versus protoplasm.
Main Results:
- The relative current flow through cell walls and protoplasm was successfully calculated.
- Results indicated that whole tissue resistance is a valid indicator of protoplasm resistance.
Conclusions:
- Findings from whole tissue resistance studies are applicable to protoplasm resistance.
- This validates the use of tissue-level measurements to infer protoplasm ion permeability.
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