Effect of low doses of piracetam on conditioned-response memory in rats

Abstract

Effects of low doses of piracetam, a psychotropic nootropic, on the memory of rats are studied. A positive effect of the drug in a dose many times lower than the doses used routinely is demonstrated on a model of elaboration of the active avoidance reaction. Key Words: piracetam; low doses; memory; conditioningPiracetam is the reference psychotropic drug belonging to the class of nootropics, agents which optimize the functions of the brain, notably memory [3]. Scientists working in various laboratories have experimentally (with rats) determined the doses of the drug which improve the processes of memory: 300 and 500 mg/kg [3,7].The results of studies of the evolution of molecular mechanisms of memory have shed light on the positive effect of piracetam on memory. The modification of the brain's genome (induction of DNA synthesis) during learning has been experimentally proven.The effects exerted by low doses of various chemicals, including neuropeptides, on the functional status of animals remain unclear [1,2,6], and, hence, a study of the effects of psychotropic agents in low doses on the higher brain functions seemed to be warranted.Our purpose was to investigate the effect of low doses of piracetam on the time course of memory formation in rats. MATERIALS AND METHODSThe study was carried out with 52 outbred rats weighing 180 to 200 g. Three experimental series were performed. In the first series 29 rats were used, divided into 3 groups. Group 1 (n=14) animals were injected piracetam in low doses (1.6x10 "3 mg/kg), group 2 (n=6) the standard piracetam close (500 mg/kg), and group 3 (n=9) normal saline. In the second series of experiments the animals were divided into 2 groups. Group 1 (n=8) received the drug in the aforesaid low dose, group 2 (n=7) norreal saline. In the third series the animals were injected low doses of the drug (n=8) or normal saline (n=7). All the solutions were injected intraperitoneally in a volume of 0.5 mi 30 min before the beginning of the experiment. Solutions of low piracetam doses were prepared as follows. The neeessary quantity of the drug was weighed with an accuracy of up to 10 -s g in thin-walled weighing bottles. Then the dry agent in the weighing bottle was put in a measuring flask with the solution. After thorough stirring the solution was poured into a 1-or 2-liter measuring flask and the volume brought to the needed quantity. The calculations were cartied out in mol/liter of solution (for example, dry agent for 1.41 mg/liter of solution is 10 -s mol/liter). Each concentration was prepared separately, without resorting to diluting ready-made solutions.

Innovative mechanisms of action for pharmaceutical cognitive enhancement: A systematic review

“…However, these drugs have multiple modes of action and produce only weak AMPA receptor activation and it is unclear how significant their ampakine actions are in producing their positive effects. Animal studies suggest memory and wakefulness enhancement properties of several racetams (Barad et al, 1998;Grossman et al, 2011;Lelkes et al, 1998;Mondadori et al, 1986;Samartgis et al, 2012;Scheuer et al, 1999;Trofimov et al, 2005;Tushmalova et al, 1995). It is noteworthy that animal experiments focused on restoring age-impaired cognitive functions (Gualtieri et al, 2002).…”

Neuroenhancement in Healthy Adults, Part I: Pharmaceutical Cognitive Enhancement: A Systematic Review

“…Although animal studies suggest memory and wakefulness enhancement properties of several racetams [170][171][172][173][174][175][176][177], the effectiveness of piracetam or piracetam-like molecules was not explored in healthy adults to date. An explanation could be that all animal data focused on restoring age-impaired cognitive functions [11].…”

Effect of Polidan on ultrastructural changes in the cerebral cortex and hippocampus of rats

“…This drug often improves learning and memory [3,5]. Polidan is the extract of sturgeon milt containing a mixture of fragments of DNA and RNA sodium salts [4].…”