Related Experiment Video

Updated: Oct 4, 2026

Isolation of Peritoneum-derived Mast Cells and Their Functional Characterization with Ca2+-imaging and Degranulation Assays
11:31

Isolation of Peritoneum-derived Mast Cells and Their Functional Characterization with Ca2+-imaging and Degranulation Assays

Published on: July 4, 2018

Degranulation of mast cells provokes a massive inflammatory reaction in the tympanic membrane

P O Eriksson1, S Hellström

  • 1Department of Clinical Sciences, Otorhinolaryngology, University Hospital of Northern Sweden, Umeå, Sweden.

The Laryngoscope
|September 25, 2001
PubMed
Abstract

Insights

Mast cells in the pars flaccida trigger tympanic membrane inflammation. This biphasic inflammatory response, involving edema and cell invasion, suggests mast cell involvement in otitis media.

Area of Science:

  • Otolaryngology
  • Immunology
  • Cell Biology

Background:

  • The pars flaccida, a part of the tympanic membrane, is densely populated with mast cells.
  • Mast cell stimulation leads to the release of inflammatory mediators.

Purpose of the Study:

  • To investigate how mast cell-derived substances induce inflammatory changes in the tympanic membrane.

Main Methods:

  • A rat model was used to study tympanic membrane inflammation.
  • Compound 48/80, a mast cell secretagogue, was applied to the tympanic membrane over four days.
  • Inflammatory changes were assessed using otological, light, and electron microscopy at various time points.

Main Results:

  • Mast cell degranulation occurred within 3 hours of compound 48/80 application.
  • A two-stage inflammatory reaction was observed: an initial edema phase followed by significant inflammatory cell infiltration.
  • Both pars flaccida and pars tensa were affected, with earlier changes noted in the pars flaccida.

Conclusions:

  • Mast cells in the pars flaccida can induce significant tympanic membrane inflammation.
  • The observed biphasic inflammatory pattern mirrors that seen in experimental otitis media.
  • These findings suggest a potential role for mast cells in the pathogenesis of middle ear inflammation.

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