Therapeutic time window of methylprednisolone in acoustic injury.
OBJECTIVE
This study aims to investigate the therapeutic time window of methylprednisolone in acoustic injury.


BACKGROUND
Although glucocorticoids have been widely used in the treatment of acoustic injury, the therapeutic time window of glucocorticoids in acoustic injury has never been examined.


METHODS
Mice were exposed to 4-kHz pure tone of 128-dB sound pressure level for 4 hours. Auditory brainstem response was examined before, immediately after, and 2 weeks after acoustic overexposure.


RESULTS
Methylprednisolone significantly improved the auditory brainstem response threshold shifts 2 weeks after acoustic overexposure when it was administered before or immediately after acoustic overexposure, but not when administered 3 hours after acoustic overexposure.


CONCLUSIONS
The present findings suggest that methylprednisolone possesses protective effects against acoustic injury of the cochlea with a short therapeutic time window.
Tabuchi
Keiji
K
Department of Otolaryngology, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Japan. ktabuchi@md.tsukuba.ac.jp
Murashita
Hidekazu
H
Sakai
Shuhei
S
Hoshino
Tomofumi
T
Uemaetomari
Isao
I
Hara
Akira
A
D000704:Analysis of Variance; D000818:Animals; D001300:Audiometry, Evoked Response; D001309:Auditory Threshold / Q000187:drug effects*; D016057:Evoked Potentials, Auditory, Brain Stem; D005260:Female; D005938:Glucocorticoids / Q000008:administration & dosage* / Q000627:therapeutic use; D006198:Hair Cells, Auditory / Q000187:drug effects / Q000473:pathology; D006317:Hearing Loss, Noise-Induced / Q000188:drug therapy*; D008775:Methylprednisolone / Q000008:administration & dosage* / Q000627:therapeutic use; D051379:Mice; D009622:Noise / Q000009:adverse effects; D013997:Time Factors; D016896:Treatment Outcome
D005938:Glucocorticoids; D008775:Methylprednisolone