[The effects of salicylate on noise-induced hearing loss in the guinea pig].
OBJECTIVE
To investigate the effects of salicylate on noise-induced hearing loss (NIHL) in guinea pigs.


METHODS
The animals were allocated into four groups (salicylate + noise, saline + noise, noise only and salicylate only) and were exposed to a 4 kHz octave band noise at 105 dB SPL for 2 hours for 5 consecutive days. Dynamic changes of ABR thresholds evoked by clicks were monitored. After physiological examination, the cochleae were processed for the morphological examination by light microscopy.


RESULTS
Mean thresholds of ABRs in the experimental group obtained on 5th day of the noise exposure was positively lower than the control groups (P < 0.05). The similar trends of ABR changes were found during other exposure days and after exposure, but the differences were not statistically significant. In the experimental group, there were 37.00 +/- 8.89 hair cell loses as assessed by nucleus staining, and 3.20 +/- 1.07 hair cells with nuclear deformation. The noise group had 74.11 +/- 10.28 hair cell loses and 10.43 +/- 9.71 hair cells with nuclear deformation, whereas the saline group had 63.60 +/- 7.97 hair cell loses and 20.80 +/- 15.48 hair cells with nuclear deformation. The difference between two groups was significant (P < 0.05).


CONCLUSIONS
The results suggest that administration of salicylate facilitates the recovery of cochlear hearing and reduces damage to hair cells after noise exposure.
Yu
N
N
Institute of Otorhinolaryngology, Chinese PLA General Hospital, Beijing 100853.
Li
X
X
Hu
B
B
D000818:Animals; D003051:Cochlea / Q000473:pathology; D016057:Evoked Potentials, Auditory, Brain Stem / Q000187:drug effects; D006168:Guinea Pigs; D006198:Hair Cells, Auditory / Q000187:drug effects / Q000473:pathology; D006317:Hearing Loss, Noise-Induced / Q000188:drug therapy* / Q000503:physiopathology; D012459:Salicylates / Q000008:administration & dosage / Q000494:pharmacology*
D012459:Salicylates