Effect of aminoglycoside otic drops on isolated cochlear outer hair cells with and without liver extract activation.

Objective: To assess the ototoxicity of commercially available Gentacidin and TobraDex ear drops with and without liver extract activation using isolated cochlear outer hair cells (OHCs).

Material And Methods: OHCs from adult chinchilla cochleae were exposed to standard bathing solution (SBS), liver extract alone and Gentacidin and TobraDex ear drops with and without liver extract. All experiments were performed at an osmolality of 305 +/-5 mOsm, at room temperature and for up to 60 min.

Protective effect of corticosteroid against the cytotoxicity of aminoglycoside otic drops on isolated cochlear outer hair cells.

Objectives: Otic drops are commonly used not only for otitis externa but also for otorrhea in the presence of tympanic membrane perforation or tympanostomy tube. Many studies demonstrated the ototoxicity of aminoglycoside. In our previous study, we observed that gentamicin (GM), when activated with liver extract, demonstrated significant cytotoxicity.

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.