MATERIAL and METHODS: Thirty-two Wistar albino rats were randomly divided into four groups: control (i.p. physiological saline), SBT (i.p. 200 mg/kg/48h SBT extract), stress (i.p. physiological saline; 6-h cold plus immobilization stress) and SBT+stress (i.p. 200 mg/kg/48h SBT; 6-h cold plus immobilization stress).* In liver and brain tissues 3-nitrotyrosine levels were determined by ELISA while total antioxidant capacity, total thiol, total glutathione, total nitrite+nitrate levels, superoxide dismutase and glutathione peroxidase activities were measured using colorimetric methods.

RESULTS: In the SBT+stress group, the total glutathione levels and glutathione peroxidase activities were significantly higher in both tissues, whereas the total nitrite+nitrate levels and superoxide dismutase activities decreased compared with the stress group. The 3-nitrotyrosine levels as oxidative and nitrosative stress markers were found to be significantly higher in SBT+stress group in both tissues than in the control. No significant differences were found between the stress and SBT+stress groups in the liver.

CONCLUSION: The results show that SBT has antioxidant properties against cold plus immobilization stress-induced oxidative and nitrosative stress and that it can be recommended as a natural antioxidant and nutritional supplement. Keywords : Brain, Liver, Nitrosative stress, Oxidative stress, Sea buckthorn