Methods: Sixteen rabbits with a mean weight of 2.68±0.36 kg were randomly assigned either to group NAC (n=8; receiving NAC) or group C (n=8; control group). They underwent a 30-minute period of spinal cord ischemia with double-clamp technique by clamping the abdominal aorta near below the left renal artery and near above the aortic bifurcation. Fifteen minutes before clamping, rabbits received either intravenous NAC (200 mg/kg; group NAC) or normal saline (group C). The subjects were monitored for 24 hours postoperatively and neurological scores were estimated using Tarlov scoring system. In spinal cord tissue samples, levels of malondialdehyde and gluthathione were also measured.
Results: The mean Tarlov score in the treated subjects was significantly higher compared to the controls (3.38±1.30 vs 0.25±0.46; p<0.001). Histopathological examination revealed that the integrity of the spinal cord was relatively preserved in the NAC group, whereas spinal cords from controls indicated evidences of acute neuronal injury. Spinal tissue malondialdehyde levels were significantly lower in the NAC group (21.57±1 vs 30.4±0.76; p<0.001), whereas glutathione levels were significantly higher (1.73±0.10 vs 1.41±0.05; p<0.001).
Conclusion: In this experimental model of spinal cord injury, NAC provided clinical and histopathological improvement. It is suggested that the effects of NAC are owing to its capacity to reduce oxidative stress and enhance the antioxidant properties of the tissues.