[Effect of nitric oxide and nitric oxide synthase on sensorineural hearing loss secondary to secretory otitis media].
OBJECTIVE
To evaluate the effect of nitric oxide synthase (NOS) and nitric oxide(NO) on sensorineural hearing loss (SNHL) secondary to secretory otitis media (SOM).


METHODS
Samples of middle ear effusion were collected at the time of tympanocentesis from 16 cases of SOM with SNHL(group A) and 16 cases of SOM without SNHL(group B). And the concentration of NO and NOS activity in middle ear effusion were detected by colorimetric assay (Griess method).


RESULTS
The concentration of NO in group A (181.19 +/- 44.31) micromol/L was significantly higher than that in group B (137.00 +/- 40.67) micromol/L (P < 0.01). The NOS activity in group A (97.69 +/- 29.62)U was also significantly higher than that in group B (75.50 +/- 26.99)U (P < 0.05).


CONCLUSIONS
Excess generation of NO in middle ear effusion which synthesized by NOS may hurt inner ear directly by its cytotoxic action or enhance local inflammatory reaction with other inflammatory factors. This study suggests that NO play a significant role in the process and pathogenesis of SNHL secondary to SOM.
Chen
Feng
F
Department of Otolaryngology, Drum Tower Hospital, Affiliated to Nanjing University Medical College, Nanjing, 210008, China. kaisachen@163.com
She
Wandong
W
Dai
Yanhong
Y
Shen
Xiaohui
X
Qian
Xiaoyun
X
Jiang
Ping
P
Gao
Xia
X
D000328:Adult; D001301:Audiometry, Pure-Tone; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000209:etiology / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D010034:Otitis Media with Effusion / Q000150:complications / Q000378:metabolism*
D009569:Nitric Oxide; D019001:Nitric Oxide Synthase