The antioxidant action of N-acetylcysteine on gentamicin-induced acute tubular necrosis in rats

Purpose: The aim of this study was to investigate whether N- acetylcysteine has an antioxidant effect on gentamicin-induced acute tubular necrosis. Method: Wistar-albino rats (n = 22) were used for the study. Rats were randomly assigned to three groups. 1. Gentamicin group (G) were injected with gentamicin, i.p. at a dose of 100 mg/kg/day for a period of 8 days (n = 8). 2. N-acetylcysteine group (NAC) were injected with the same dose of gentamicin and additionally N-acetylcysteine (150 mg/kg/day i.p.) for 8 consecutive days (n = 6). 3. Control group (C) were injected intraperitoneally (i.p.) with 0.9% w/v NaCl at the same volume as gentamicin for a period of 8 days (n = 8). The animals were anesthetized with ether inhalation, 24 h after the last infection and right and left kidneys were then excised. Left kidneys were used for determination of thiobarbituric acid reacting substances (TBARS) of lipid peroxidation, lactic acid, glutathione peroxidase (Gpx) and superoxide dismutase (SOD). Right kidneys were divided into two sections and fixed for light and electron microscopy. Results: Levels of TBARS and lactate (P < 0.001) which were raised by gentamicin administration were decreased with N-acetylcysteine treatment. NAC treatment also improved Gpx (P < 0.05) and SOD (P < 0.001) activities which were suppressed by gentamicin administration. Our biochemical findings were supported by histopathologic examinations. The NAC-treated rats showed milder histopathological findings. Conclusion: NAC has an antioxidant effect on gentamicin-injured kidney tissue by various mechanisms, as it has on many other tissues.