Protective Effects of Aminoguanidine against Sodium MetavanadateInduced Spatial Memory Retention Impairment in Morris Water Maze

Background: Vanadium is a potential neurotoxic agent widely distributed in the environment. Understanding the neurotoxic mechanisms of vanadium on learning and memory seems necessary. Methods: We investigated the timedependent (1week, 2 week and 4week) effects of sodium metavanadate (SMV) (25 mg/kg/day; pretraining oral administration) and 4day intraperitoneal injections of aminoguanidine (AG) as a selective inducible nitric oxide synthase inhibitor (10, 50, and 100 mg/kg) on spatial memory retention in Morris water maze. Animals were trained for 4 days and tested 48 h after the last training trial. Results: The data showed that 4week oral pretreatment with SMV (25 mg/kg/day) induced spatial memory retention deficits and decreased the time spent in the target quadrant. We found that 4day administration of different doses of AG during training trials significantly decreased the time and distance of finding the hidden platforms. Additionally, SMVinduced spatial memory retention impairments were prevented in animals received combined SMV (25 mg/kg/day, 4 weeks) and AG (10 mg/kg/day, 4 days). Conclusion: Our findings showed the protective role of AG on SMVinduced spatial memory retention deficits.