Effect of intratympanic N-acetylcystein (NAC) on vestibulotoxicity model formed with intratympanic gentamicin in Guinea pigs.

Abstract

BACKGROUND: N-acetylcysteine (NAC) can protect against this damage. AIM: To evaluate the effect of intratympanic NAC on the vestibulotoxicity model formed with intratympanic gentamicine in guinea pigs. DESIGN: Experimental Animal Study. METHODS: Guinea pigs were randomly divided into three groups. Group1 (control), group2 was treated with intratympanic(IT) gentamicin and group3 was treated with IT gentamicin + NAC. A single dose of NAC was applied on the 1st,3rd, and5th days. Cervical-vestibular evoked myogenic potentials (c-VEMP) measurements and blood samples were taken from the guinea pigs on the day 0,10,30. RESULTS: In group2 on day 10 c-VEMP latency was prolonged and on day 30 c-VEMP responses were lost in half of animals. A partial loss of c-VEMP values was observed in the group3. Serum total antioxidant capacity (TAC) and superoxide dismutase (SOD) activity in group3 (on the 7th and 30th day) were significantly higher than those in the group2. Tissue SOD and glutathione (GSH) were lower, while the malondialdehyde (MDA) and lipid hydroperoxide (LOOH) were the higher in group2. CONCLUSION: Gentamicin induced loss in c-VEMP responses and NAC played an effective role in reducing this loss which were confirmed by oxidative capacity at tissue and serum level.