Abstract
Noise and aminoglycosides initially attack cochlear outer hair cells (OHCs). Distortion product otoacoustic emissions (DPOAEs) are used for the early diagnosis of damage to OHCs. The effects of sub-damaging doses of amikacin, an aminoglycoside antibiotic agent, on noise-induced hearing loss (NIHL) were examined in guinea pigs. Animals were grouped by gender and exposed to broadband noise at 105 dB SPL for 12 h and/or injected i.m. with either amikacin (100 mg/kg/day) or saline for 10 days. Auditory brainstem response (ABR) thresholds, along with DPOAE amplitudes, were measured serially before and after noise exposure. DPOAE amplitudes decreased and ABR thresholds elevated immediately after noise exposure and then gradually recovered. At all frequencies, the emission amplitudes recovered completely to pre-exposure baseline values by 4 days after noise exposure. There was no effect of amikacin on either the ABR threshold or DPOAE amplitudes, in animals treated with amikacin only. However, amikacin significantly prolonged the effect of noise exposure on DPOAE amplitude but not on the noise-induced temporary threshold shift (TTS) of the ABR. In animals treated with a combination of noise and amikacin, significant changes in DPOAE amplitudes were still observed at 4 weeks after cessation of noise exposure. No gender difference in the responses to noise and/or amikacin could be demonstrated. The present findings indicate that even sub-damaging dosages of amikacin might impair recovery from NIHL in guinea pigs.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.