Does exogenous nitric oxide influence tympanosclerosis? An experimental study

Int J Pediatr Otorhinolaryngol. 2008 Dec;72(12):1845-8. doi: 10.1016/j.ijporl.2008.09.008. Epub 2008 Oct 21.


Objective: We aimed to elucidate the effects of exogenous nitric oxide application via myrigotomized rat tympanic membranes on tympanosclerosis.

Materials and methods: Forty male rats were included in the study. After myringotomy, nitric oxide was given to the left tympanic cavities and saline was given to the right as the control group. The procedure was repeated 3 times with weekly intervals. Three months after the first procedure, otomicroscopic examination was made and the rats were sacrificed for histologic examination.

Results: Neither otomicroscopic examination, nor histologic examination of middle ears and tympanic membranes revealed any significant difference between the right and left sides. Tympanic membrane thicknesses were also similar on both sides without showing any significant difference.

Conclusions: Data from this study indicate that exogenous nitric oxide application did not change the occurence of tympanosclerosis in the rat model. Other cytokine interactions are needed to start the reaction sequence leading to tympanosclerosis.

MeSH terms

  • Animals
  • Disease Models, Animal
  • Ear, Middle / drug effects
  • Ear, Middle / pathology
  • Male
  • Microscopy
  • Nitric Oxide Donors / pharmacology*
  • Otosclerosis / drug therapy*
  • Otosclerosis / pathology*
  • Rats
  • Rats, Sprague-Dawley
  • Triazenes / pharmacology*
  • Tympanic Membrane / drug effects
  • Tympanic Membrane / pathology*
  • Tympanic Membrane / surgery


  • 1-hydroxy-2-oxo-3,3-bis(2-aminoethyl)-1-triazene
  • Nitric Oxide Donors
  • Triazenes