Effect of nitric oxide on mucin production in experimental otitis media.
OBJECTIVE
The purpose of this study was to determine the role of nitric oxide (NO) in the pathogenesis of mucoid otitis media (OM) in lipopolysaccharide (LPS)-induced OM.


METHODS
OM was induced in chinchillas by injecting S-nitroso-N-acetylpenicillamine (SNAP), LPS, and LPS + SNAP into the superior bullae. Auditory brainstem response thresholds were measured every 24 hours. Samples of middle ear fluid were collected and analyzed for mucin by the periodic acid-Schiff method. At the end of each experiment, temporal bones were harvested for histopathologic study.


RESULTS
Mucin concentration was greatest in the LPS + the SNAP group and least in the SNAP-alone group. Auditory brainstem response threshold was highest in the LPS group and lowest in the SNAP group, although not significantly. Histopathology showed the greatest mucosal thickening and inflammation in the LPS + SNAP group.


CONCLUSIONS
The addition of NO in LPS-induced OM increased the mucin concentration in middle ear fluid and increased mucosal thickness and inflammation in middle ear mucosa.


CONCLUSIONS
In the OM disease process, NO may contribute to the pathogenesis of mucoid OM.
Division of Otolaryngology-Head adn Neck Surgery, Loma Linda University School of Medicine, Loma Linda, California, 92354, USA. tjung1790@aol.com
Paul
P
Martin
Duk-Joo
DJ
Choi
Tae-Hoon
TH
Jinn
Joshua G
JG
Cohen
Earnest O
EO
John
Morrill T
MT
Moorehead
Claire S
CS
Kaura
Samantha H
SH
Kaura
Timothy T k
TT
Jung
D000818:Animals; D002682:Chinchilla; D016057:Evoked Potentials, Auditory, Brain Stem; D008070:Lipopolysaccharides / Q000009:adverse effects; D009077:Mucins / Q000096:biosynthesis*; D009569:Nitric Oxide / Q000502:physiology*; D010033:Otitis Media / Q000139:chemically induced / Q000473:pathology / Q000503:physiopathology*; D012486:Salmonella typhimurium
D008070:Lipopolysaccharides; D009077:Mucins; D009569:Nitric Oxide