Stretch induces granule exocytosis in toad urinary bladder

Area of Science:

• Physiology
• Cell Biology
• Epithelial Transport

Background:

• The toad urinary bladder epithelium is a model system for studying epithelial transport.
• Hormonally-induced changes in permeability are well-documented.
• The role of granule exocytosis in these permeability changes remains unclear.

Purpose of the Study:

• To investigate the effect of mechanical stretch on exocytosis in toad urinary bladder granular cells.
• To highlight the importance of the stretch factor in physiological studies.

Main Methods:

• Utilized freeze-fracture electron microscopy.
• Examined granular cells of the toad urinary bladder epithelium.

Main Results:

• Demonstrated that mechanical stretch induces a burst of exocytosis in granular cells.
• Provided evidence for stretch-induced exocytosis.

Conclusions:

• Mechanical stretch is a significant factor influencing exocytosis in the toad urinary bladder epithelium.
• Standardizing the stretch parameter is recommended for future physiological and morpho-functional studies of this system.