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CELL PENETRATION BY ACIDS : V. NOTE ON THE ESTIMATION OF PERMEABILITY CHANGES.
1Contributions from the Bermuda Biological Station for Research, No. 139, and from the Zoological Laboratory, Rutgers College, New Brunswick.
The Journal of General Physiology
|October 30, 2009
Summary
Faradic stimulation speeds acid penetration into Chromodoris zebra mantle tissue, while anesthetics slow it. Tissue tension also facilitates both acid penetration and pigment diffusion, challenging traditional permeability measures.
Area of Science:
- Marine Biology
- Physiology
Background:
- Understanding the permeability of marine invertebrate tissues is crucial for ecological and physiological studies.
- The mantle tissue of Chromodoris zebra, a marine gastropod, presents a unique model for studying cellular transport mechanisms.
Purpose of the Study:
- To investigate factors influencing acid penetration into Chromodoris zebra mantle tissue.
- To evaluate the role of electrical stimulation, anesthetic treatment, and mechanical tension on tissue permeability.
- To reassess the reliability of pigment diffusion as an indicator of tissue permeability.
Main Methods:
- Local faradic stimulation was applied to the mantle tissue.
- Anesthetic solutions were used for brief treatment of the tissue.
- Mechanical tension was artificially applied to the tissue.
- Acid penetration and pigment diffusion were monitored.
Main Results:
- Faradic stimulation significantly accelerated acid penetration into the mantle tissue.
- Anesthetic treatment effectively retarded acid penetration.
- Both acid penetration and spontaneous outward pigment diffusion were facilitated when the tissue was artificially put under tension.
- Spontaneous outward pigment diffusion was found to be an inadequate criterion for assessing tissue permeability.
Conclusions:
- Tissue excitability, influenced by electrical stimulation and anesthetics, plays a significant role in regulating acid penetration.
- Mechanical tension can alter membrane properties, facilitating both solute transport and pigment efflux.
- Traditional measures of permeability, such as pigment diffusion, may not accurately reflect the complex transport processes occurring in marine invertebrate tissues.
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