Mesothelial intercellular junctions and pathways

Cell and Tissue Research
|October 1, 1976
PubMed

Insights

Mesothelial cells in mouse peritoneum exhibit vesicles and tubules potentially involved in transport across the cell barrier. These structures may relate to existing theories on cellular transport mechanisms.

Area of Science:

  • Cell Biology
  • Physiology
  • Anatomy

Background:

  • Mesothelial cells form a critical barrier in the peritoneum.
  • Understanding transport mechanisms across this barrier is vital for physiological studies.

Purpose of the Study:

  • To investigate the ultrastructure of mouse peritoneal mesothelial cells.
  • To explore the role of observed cellular structures in transport phenomena.

Main Methods:

  • Freeze-etch electron microscopy was used to prepare mesothelial cells from mouse peritoneum.
  • Cellular structures, including vesicles and tubules, were examined at the apical and basal surfaces and within the cytoplasm.

Main Results:

  • Vesicles were observed invaginating both apical and basal cell surfaces, with few seen in the cytoplasm.
  • Long, tortuous tubular profiles were frequently associated with these vesicles within the cytoplasm.
  • Leaky occludens junctions were identified, but their specific arrangement (macular or zonular) remains undetermined.

Conclusions:

  • The observed vesicles and tubules may play a role in transport across the mesothelial barrier.
  • Findings are discussed in the context of the pore theory and the stomata concept of cellular transport.
  • Further investigation is needed to establish the precise nature and function of these structures and junctions.

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