New aspects of the neurophysiological mechanism of the action of nootropic preparations

The influence of nootropic drugs on EEG spectral power of the cortex and hippocamp was studied in resting rats. All these drugs had a specific action on EEG spectral power, causing an increase and stabilization of maximum basic distribution peak of the EEG spectral power. Such action may be attributed to better organization of rhythmic activity in theta-range. The drugs also decreased interhemispheric asymmetry of the cortical and hippocampal EEG. The authors suggest that the increase and improvement of the basic rhythmic activity in the brain and an increased level of distant (spatial) synchronization form the basis for the nootropic drug effect.     

Clinico-electroencephalographic indices of the parkinsonian syndrome induced by MPP+ in rats

The bilateral intranigral injection of 1-methyl-4-phenyl-pyridinium ion (MPP+) (10 g) produced significant oligokinesia, rigidity and weak tremor in rats. The extrapyramidal disturbances manifest a high-amplitude paroxysmal activity (PA) in the structures studied. It was found that the Pa was remarkable and more stable in the caudata nucleus than in other brain structures. It is PA that gives us the real basis to conclude the formation of the generator of pathologically enhanced excitation (GPEE) in the caudata nuclei. The analysis of PA dynamics revealed that the formation of the GPEE in the caudata nuclei correlated with development of parkinsonian syndrome (PS).     

Relations between anxiolytic effects of diazepam and changes in the EEG spectral power

The influence of diazepam (1; 5; 10 mg/kg, i. p.), chlorpromazine (1 mg/kg) and amphetamine (1; 5 mg/kg) on the Fourier's spectral EEG power of sensomotor cortex and dorsal hippocampus and conflict behavior freely moving albino and cotton (Sigmondon hispidus) rats was studied. Effects of diazepam (5 mg/kg) in cotton rats were similar, but influence on the theta-activity was more expressed. Correlation between slowing of theta-activity and extent of anxiolytic effect in conflict situation was showed. On the basis of the results obtained the authors discuss possible mutual relations between the influence of diazepam on EEG and anxiolytic effect of benzodiazepines.     

Effect of 3-hydroxypyridine derivatives on the central nervous system

Experiments on mice and rats were made to study the effect of inhibitors-antioxidants (3-hydroxypyridine derivatives) on the central nervous system. It was established that 3-hydroxypyridine derivatives (50 to 200 mg/kg) possess a broad spectrum of psychotropic effects. They cause normalization of behavior in conflict situations, exert an antiaggressive and anticonvulsant action (antagonism with corazol), are capable of potentiating the hypnotic effect of barbiturates, and of suppressing the animals' motor activity if given in high doses. Most compounds under study have antihypoxic and antiamnestic effects.     

Neural Crest—An Unusual Population of Embryonic Cells

Molecular Biology - The neural crest (NC) in embryos of vertebrates represents a cell population formed at the border of the neural plate. These cells retain pluripotency, express a set of specific...     

Geropsychotropic properties of an antioxidant of the 3-hydroxypyridine class in an experiment

Comparative experimental investigation of albino male rats 3 and 16 months old has been performed. 16-month-old rats demonstrated age-dependent functional insufficiency in some behavioural tests. 2 month injection of 3-hydroxypyridine antioxidant (50 mg/kg/day) normalized memory function, motor skill learning and motor coordination function in 16-month-old rats.     

Cross-action of extracellular stress adaptation factors in microorganisms]

The capacity of microorganisms from different taxa to adapt to stress conditions with the help of extracellular factors exhibiting similar mechanisms of action was demonstrated. The action of adaptation factors synthesized by the enteric bacterium Escherichia coli, the soil bacterium Bacillus subtilis, and the yeast Candida utilis was characterized in biological tests. It was demonstrated that the factor of accelerated adaptation to new media (FAANM) and the growth-rate-reducing factor (factor X(II)), which decreases the rate of exponential culture growth, were synthesized by all microorganisms tested. Antilysin (factor X(I)), which accelerates cell adaptation to N-ethylmaleimide, was not produced by C. utilis.     

Modelling expected trout ranges under current and future water temperature regimes in the Eastern Cape,South Africa

Different values have resulted in conflicts between anglers and conservation lobbies in the management of trout in South Africa. Key to the conflict is the demarcation of boundaries to areas in which brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss currently occur, or are likely to establish following stocking for angling. To provide a longer-term perspective on these areas, we developed models to link salmonid biological thermal thresholds to elevation. These, when applied spatially using a digital elevation model with a probability of occurrence model, provided the basis for estimating potentially available thermal habitat for these two cold water species. Here, we acknowledge that other variables (stocking history; river connectivity) also play a role in understanding trout distributions. Using a simple scenario of an increase in mean daily water temperatures of 2 °C, we demonstrated that both brown and rainbow trout are likely to exhibit considerable range reductions in the future. Because it is possible that these range restrictions will result in an increasing desire to introduce trout into areas above their current distribution limits for the maintenance of angling opportunities, conservation managers should prioritise these areas, with management interventions seeking to understand what will help to limit introductions.