RESUMEN
The effects of four nootropic drugs (piracetam, aniracetam, meclofenoxate and fipexide) on the impaired cognitive functions by the dopamine-beta-hydroxylase inhibitor diethyldithiocarbamate (DDC) were investigated in albino rats. The changes in learning and memory were studied by the two-way active avoidance with punishment reinforcement (shuttle box). DDC injected intraperitoneally at a dose of 300 mg/kg in the course of the 5-day shuttle box training significantly impaired learning and retention. The 10-day treatment (5 days before and 5 days during training) with piracetam 600 mg/kg, aniracetam 50 mg/kg, meclofenoxate 100 mg/kg and fipexide 10 mg/kg completely abolished the learning- and memory-impairing effect of DDC. The role of the NA-ergic neurotransmitter system for the DDC-induced disturbances in cognition as well as for the protective effects of nootropic drugs was discussed.