EFFECTS OF CHRONIC LITHIUM ON OTOTOXICITY INDUCED BY GENTAMICIN AND AMIKACIN IN GUINEA-PIGS

The effects of chronic lithium co-therapy on the expression of gentami cin and amikacin ototoxicity were tested in guinea-pigs. Intramuscular injection of different doses of gentamicin (5, 10 mg/kg/day) and amik acin (150, 300 mg/kg/day) for three weeks, induced hearing loss consis tent with the established pattern of aminoglycoside ototoxicity. Lithi um salts remains one of the most widely used treatment for depressive illness. Administration of lithium chloride (600 mg/l, 35 days) in dri nking water changed auditory brainstem response in a time-dependent ma nner. Pretreatment of animals with lithium chloride after seven days i nduced significant alterations in wave latency and interval. The prese nt study assesses the protective effects of chronic lithium on gentami cin-induced ototoxicity in guinea pig. The results suggest that durati on of lithium administration may be involved in auditory brainstem res ponse changes and the observations could be accounted for, at least pa rtially, by lithium- and aminoglycosides-induced perturbations of the phosphoinositide cascade within the inner ear.