The effects of ascorbic acid and oxiracetam on scopolamine-induced amnesia in a habituation test in aged mice.

The effects of a nootropic drug, oxiracetam (50-100-200 mg/kg ip), and a potent antioxidant agent, ascorbic acid (62.5-125-250 mg/kg ip), administered alone or in combination, were investigated on scopolamine-induced amnesia in a mouse habituation test. The light-dark aversion test was selected and was carried out in aged mice. Habituation to the test box occurred over a 3-day period, control mice showing a significant between-day increase in the time spent in the dark box, but not in the number of transitions. On Day 4, following post-trial administration over a 3-day period of oxiracetam (50-100 and 200 mg/kg ip) or ascorbic acid (62.5-125 and 250 mg/kg ip), a significant between-day increase in the time spent in the black area, but not in the number of transitions, was found. The combination of oxiracetam (100 mg/kg ip) with ascorbic acid (125 mg/kg ip) produced a similar pattern of results. The acute administration of scopolamine (0.25 mg/kg ip) to mice treated over a 3-day period with vehicle disrupted the habituation response. In mice that had received the 3-day treatment with oxiracetam or ascorbic acid or its combination, scopolamine failed to alter significantly the learning pattern. In conclusion, these data demonstrate that ascorbic acid, alone or in combination with oxiracetam, may prevent experimentally induced amnesia in aged mice.