Clarification of the intercellular space phenomenon in toad urinary bladder
1Laboratory of Renal Biophysics, The Massachusetts General Hospital, and Harvard Medical School, 02114, Boston, Massachusetts.
The Journal of Membrane Biology
|November 2, 2013
Summary
Vasopressin increases intercellular space size in toad bladder epithelium, independent of osmotic gradients. This suggests smooth muscle tone changes significantly impact epithelial geometry, not just water flow.
Area of Science:
- Cell biology
- Physiology
- Epithelial transport
Background:
- Vasopressin is known to alter epithelial structure.
- Intercellular spaces in toad bladder epithelium are sensitive to hormonal and osmotic stimuli.
- Previous studies suggest vasopressin affects epithelial cell junctions.
Purpose of the Study:
- To investigate the effect of vasopressin on toad bladder epithelium geometry.
- To determine if vasopressin-induced changes are dependent on osmotic gradients.
- To explore the role of smooth muscle tone in epithelial morphology.
Main Methods:
- Microscopic examination of toad bladder epithelium.
- Application of vasopressin with and without osmotic gradients.
- Assessment of glutaraldehyde fixation artifact.
- Morphological analysis of epithelial-smooth muscle connections.
Main Results:
- Vasopressin increased intercellular space size in toad bladder epithelium.
- This effect was observed irrespective of osmotic gradients.
- Glutaraldehyde fixation did not cause the observed changes.
- Morphological evidence showed continuity between epithelium and smooth muscle.
Conclusions:
- Vasopressin alters epithelial geometry by increasing intercellular spaces.
- The effect is independent of osmotic gradients and fixation artifacts.
- Smooth muscle tone significantly influences epithelial geometry, alongside water flow.
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