EFFECT OF ACUTE EXPOSURE TO 3-NITROPROPIONIC ACID ON ACTIVITIES OF ENDOGENOUS ANTIOXIDANTS IN THE RAT-BRAIN

The response of endogenous antioxidants to acute exposure of the mitoc hondrial inhibitor, 3-nitropropionic acid (3-NPA), was investigated in selected rat brain regions. Rats treated with 3-NPA (30 mg/kg, s.c.) were sacrificed at 30, 60, 90 and 120 min after injection to examine t he alterations in reduced glutathione levels (GSH), and activities of antioxidant enzymes, superoxide dismutase (SOD), glutathione peroxidas e (GPx), and catalase (CAT) in the hippocampus (HIP), frontal cortex ( FC), and caudate nucleus (CN). CAT activity increased in the HIP 90 mi n after 3-NPA treatment. While cytosolic copper/zinc SOD (CuZn-SOD) an d mitochondrial manganese SOD (Mn-SOD) levels increased in the FC at 1 20 min, only the Mn-SOD increased in the CN 90 min after treatment. Th e activity of GPx decreased in the HIP 120 min after 3-NPA injection. When compared with the control, administration of 3-NPA led to GSH dep letion in HIP within 120 min. The depletion of GSH and induction of an tioxidant enzyme activities after the 3-NPA exposure suggest condition s favorable for oxidative stress. Published by Elsevier Science Irelan d Ltd.