Protective effect of carnosine on excitable structures of the auditory apparatus in albino rats with acute acoustic trauma.

We studied the effect of natural antioxidant carnosine on Wistar rats with experimental acoustic trauma of the auditory apparatus. Repeated intraperitoneal injection of carnosine in a dose of 200 mg/kg 12 and 0.5 h before modeling of acute acoustic trauma decreased the severity of degenerative and atrophic changes in the nuclei of hair cells in the cochleae. Carnosine compensated the deficiency of tissue antioxidant systems and suppressed generation of lipid peroxidation products in tissues of the membranous cochlea and auditory cortex of the temporal lobes. Carnosine holds much promise as a nonspecific otoprotector.

Natural antioxidant L-carnosine inhibits LPO intensification in structures of the auditory analyzer under conditions of chronic exposure to aminoglycoside antibiotics.

Intragastric administration of L-carnosine suspension to Wistar-Kyoto rats 3 days before and after 7-day course of intraperitoneal injections of ototoxic aminoglycoside antibiotic kanamycin compensated expenditures of tissue antioxidant systems and significantly eliminated kanamycin-induced intensification of MDA production in tissues of the membrane part of the cochlea and in the auditory cortex of the temporal lobe. L-NAME (competitive NO synthase inhibitor) also inhibited LPO, increased total antioxidant activity, and decreased ototoxicity of kanamycin, which confirms the contribution of NO into LPO intensification under conditions of aminoglycoside treatment. Inhibition of pathological intensification of LPO processes and increase in total antioxidant activity under conditions of induced acute aminoglycoside ototoxicity characterizes L-carnosine as a highly effective otoprotector.