Taurine attenuates aminoglycoside ototoxicity by inhibiting inducible nitric oxide synthase expression in the cochlea.

This study explored the potential protective role of taurine against aminoglycoside ototoxicity and the involvement of inducible nitric oxide synthase (iNOS) in the process. Guinea pigs, which received a single intravenous administration of gentamycin (100 mg/kg) followed by one large dose of furosemide (90 mg/kg, intravenously) were used as subjects. A rapid and profound hearing loss was seen in these animals 3-day posttreatment with iNOS expression upregulated in the cochlea. However, pretreatment with taurine prevented the hearing damage with decreased iNOS expression, similar to the effect of aminoguanidine, a selective inhibitor of iNOS. These findings suggest that taurine provides protection against the acute gentamycin/furosemide ototoxicity possibly by downregulating iNOS expression in the cochlea.