Total antioxidant status in the blood serum of rats exposed to N-nitroso compounds and nitric oxide synthase inhibitors

In this study, the total antioxidant status (TAS) was assayed in the blood serum of rats pretreated per os with either N-nitrosodiethylamine (NDEA) (0.1 mg/kg b.w./day) or N-methyl-N-nitrosourea (NMU) (0.1 mg/kg b.w./day) for 30 days. The animals were also dosed per os with spermidine (SPR) (10 mg/kg b.w./day) for a first 21 day period, and Nomega)-nitro-L-arginine methyl ester (L-NAME) (10 mg/kg b.w./day) given to animals for 3 days (days 22-24), respectively. Nitric oxide synthase (NOS) inhibitor, L-NAME was found to mitigate TAS levels in the blood serum of rats pretreated with NDEA and NMU. No such changes were found in animals dosed with L-NAME only nor even with L-NAME and spermidine, respectively. Since spermidine, also known as an inhibitor of iNOS synthesis, elevated TAS levels in rats dosed with L-NAME and NDEA/NMU, the polyamine was suggested to modify the NOS/NO origin to serve the physiological level of the total anti-oxidant status in rat blood serum.