Effects of cytidine diphosphate choline on rats with memory deficits.

The effects of cytidine diphosphate choline (CDP-choline, CAS 987-78-0) on learning and memory in rats with memory deficits were examined using behavioral methods of active avoidance with punishment reinforcement (shuttle-box), passive avoidance with punishment reinforcement (step-through and step-down), and active avoidance with positive (alimentary) reinforcement (staircase-maze). In the majority of experiments CDP-choline was applied orally at doses of 10-50 or 100 mg/kg daily for 7 days before the training session. The experiments were carried out on young-adult (aged 5 months) and old (aged 22 months) rats and on rats with a low capability for retention of learned behavior.

Effect of CDP-choline on learning and memory processes in rodents.

The effects of cytidine (5') diphosphocholine (CDP-choline) on learning and memory were studied using conditioned reflex methods for passive avoidance and active avoidance with punishment reinforcement (step-through, step-down, shuttle box and maze), for active avoidance with alimentary reinforcement (staircase maze), and the Morris water maze. The majority of experiments involved comparative studies of the nootropic drugs meclofenoxate and/or piracetam. CDP-choline was administered orally, in some of the experiments also intraperitoneally, at doses of 10-500 mg/kg body weight once or twice daily for 5 or 7 days.

Effects of citicholine and of the combination citicholine + piracetam on the memory (experiments on mice).

The memory effects of citicholine (CCh) and piracetam (Pc) were tested in experiments on mice using the training method with passive avoidance and negative reinforcement (step-through). In single doses of 25, 50, 100 and 500 mg/kg, CCh applied one hour prior to training enhanced to the same degree and statistically significantly the retention of the memory traces in tests both 24 h and 7 days after the training session; Pc in a dose of 500 mg/kg improved the retention in memory tests 24 h after training, but had no significant effect during the tests 7 days after the training. Combined application of CCh and Pc in doses which are ineffective with respect to the memory process (CCh--10 mg/kg and Pc--200 mg/kg) caused a significant enhancement of the retention during the tests both 24 h and 7 days after the training.

Age-related differences in memory and in the memory effects of nootropic drugs.

In experiments of 2-, 5-, 10- and 22-month old rats, using active avoidance with punishment reinforcement (maze and shuttle-box) and passive avoidance (step-down), we found that acquisition and retention in aged rats were impaired significantly or only as a trend. The nootropics adafenoxate, meclofenoxate, citicholine, aniracetam and the standardized ginseng extract administered orally for 7 to 10 days usually facilitated learning and improved memory in the rats of all ages. By some of the indices used the drugs gave more pronounced favourable effects in old rats, while by others better effects were observed in young or adult rats.

Memory effects of the new derivative of the p-chlorophenoxyacetic acid adafenoxate compared to the effects of some cognition-enhancing drugs in rats.

In experiments on male rats the effects of adafenoxate (Adf), meclofenoxate (Mf), piracetam (Pc) and citicholine (CCh) on learning and memory were studied using the maze active avoidance method with punishment reinforcement. The drugs tested were administered twice daily for seven days at doses of 10 and 50 mg/kg body weight for Adf, Mf and CCh and only at a dose of 50 mg/kg body weight for Pc. The effects of these drugs on scopolamine-treated and scopolamine-untreated rats were also studied using the step-through method.

Learning and memory effects of four newly-synthesized aniracetam analogues.

Four new analogues of the pyrolidine derivative with nootropic action--aniracetam--were synthesized using classical methods. The effects of the newly-synthesized compounds were tested using the step-through method for passive avoidance with negative reinforcement and the method of habituation of exploratory activity in the Opto-Varimex apparatus. Two series of experiments were performed using the step-through method: in one series aniracetam (Anc) and its analogues p-H and p-Cl were applied twice daily in a dose of 50 mg/kg for 7 days prior to the training session; retention tests were made 3 h, 24 h and 7 days after the training session.

Comparative studies on the effects of the nootropic drugs adafenoxate, meclofenoxate and piracetam, and of citicholine on scopolamine-impaired memory, exploratory behavior and physical capabilities (experiments on rats and mice).

The effects of adafenoxate (Adf), meclofenoxate (Mf), piracetam (Pc), and citicholine (CCh) on scopolamine (Scop)--impaired memory and exploratory behavior (experiments on rats) and on physical capabilities (experiments on mice) were studied. In the experiments with scopolamine (2 mg/kg i.p.

Effects of standardized ginseng extract on learning, memory and physical capabilities.

Standardized ginseng extract (G115, Pharmaton, Lugano) was administered orally at doses of 3, 10, 30, 100 and 300 mg/kg for 10 days as ten rats were used with each dose. With the "shuttle-box" method for active avoidance most pronounced effect on learning and memory was obtained by the dose of 10 mg/kg. With the "step-down" method for passive avoidance the dose of 30 mg/kg significantly improved retention.

Effect of piracetam and of standardized ginseng extract on the electroconvulsive shock-induced memory disturbances in "step-down" passive avoidance.

The effects of piracetam and standardized Ginseng extract (G115) on the memory-impairing action of electroconvulsive shock were investigated in experiments on albino rats. The changes in the memory were traced using the "step-down" conditioned reflex method of passive avoidance with negative reinforcement. Piracetam, administered in a dose of 600 mg/kg i.

Effects of extract from Rhapontcum carthamoides (Willd) Iljin (Leuzea) on learning and memory in rats.

The effects of extract from Rhaponticum carthamoides (Willd) Ijin (Leuzea) on the processes of learning and memory in rats were investigated. R. carthamoides was administered orally in doses of 0.

Effects of meclofenoxate and citicholine on learning and memory in aged rats.

The maze method for active avoidance with punishment reinforcement and the step-through method for passive avoidance with negative reinforcement were used to study the processes of learning and memory in 22-month-old rats, as well as the effects of meclofenoxate (Mf) and citicholine (CCh) on these processes. Meclofenoxate, administered in a dose of 50 mg/kg twice daily for 7 days using the maze-training method, increased the number of responses to the conditioned stimulus, when retention tests were made 24 hours and 7 days after training, whereas citicholine, applied in the same way in a dose of 10 mg/kg, shortened the latency of the responses with reinforcement during the training and increased the number of correct responses to the conditioned stimulus in retention tests 7 days after the training. With the same pattern of administration, both Mf and CCh strongly prolonged the time spent by the animals in the light chamber (i.

A study of nootropic drugs for anti-anxiety action.

The effects of adafenoxate (100 mg/kg), aniracetam (50 mg/kg), meclofenoxate (100 mg/kg), piracetam (250 mg/kg), and standardized ginseng extract-G115 (100 mg/kg) applied for five days were studied with Vogel's conflict procedure in which thirsty naive rats were periodically administered shocks for licking water. The results showed a significant anti-anxiety effect (increases in licking) with adafenoxate and meclofenoxate. Piracetam significantly suppressed licking behaviour and this effect was evaluated as anxiogenic (resulting from the non-specific stimulant action of the drug).

Effects of meclofenoxate and Extr. Rhodiolae roseae L. on electroconvulsive shock-impaired learning and memory in rats.

In experiments on albino rats, the authors studied the effects of meclofenoxate and Extr. Rhodiolae roseae on the memory-impairing action of convulsant electroshock. "Step-down" passive avoidance training with negative reinforcement was used to trace the changes in memory.

Effects of meclofenoxate on learning and memory--dependence on the experimental conditions.

In experiments on male albino rats, it was found that meclofenoxate at a dose of 100 mg/kg i. p. applied 7 days before and 5 days during shuttle-box training did not influence learning but significantly facilitated retention (retention test was given 7 days after the end of training).