RESUMO
BACKGROUND: PCBs are one of the environmental toxicants and neurotoxic compounds which induce the production of free radicals leading to oxidative stress. Vitamin C is well known as an outstanding antioxidant. We determined the protective role of ascorbate on hypothalamic antioxidant system of Aroclor 1254 exposed rats. METHODS: The rats were injected Aroclor 1254 at a dose of 2 mg/kg bw/day intraperitoneally for 30 days. One group of rats received vitamin C (100 mg/kg bw/day) orally simultaneously with Aroclor 1254 for 30 days. Twenty-four hours after last treatment, the animals were killed and hypothalamic region was separated from brain tissue. Enzymatic and non-enzymatic antioxidants such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and vitamin C were estimated. Hydrogen peroxide (H(2)O(2)), lipid peroxidation (LPO) and acetylcholine esterase (AchE) activity were determined. Serum gonadotropins such as luteinizing hormone (LH) and follicle stimulating hormone (FSH) were also assayed. RESULTS: Activities of SOD, CAT, GPx, GR, AchE and the concentration of vitamin C were decreased while an increase in H(2)O(2) and LPO were observed in hypothalamus of PCB treated animals. LH and FSH concentrations were also decreased in serum of PCB exposed animals. Vitamin C administration retrieved all the parameters significantly except serum hormonal profiles. CONCLUSION: PCB induces oxidative stress in hypothalamus by decreasing the activities of antioxidant enzymes, which can be protected by vitamin C treatment.
