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Biomedical subjects

R U Ostrovskaia

Publications and source records attributed to R U Ostrovskaia.

At least 19 recordsLinked to original sources
PubMed1993

[Behavior disorders in rats exposed to intrauterine hypoxia, and their correction by postnatal treatment with piracetam].

Hypobaric hypoxia of the pregnant rats was followed by the reduction of weight gain of the newborn pups, delayed impairment of memory (passive and active tasks) and changes of extrapolative water escape. Piracetam (200 mg/kg/day) administered at early postnatal period (from 8th to 20th day of life) corrected behavioral disturbances and physical development in rats. Postnatal therapy by nootropics didn't influence in adaptive behavior damaged by prenatal hypoxia.

Animals↗
PubMed1993

[The sodium oxybutyrate and nooglutil correction of dopamine release in the striatum of prenatally alcoholized rat pups].

The influence of prenatal exposure to ethanol on endogenous Dopamine (DA) release from perfused isolated striata of 20-day-old rats was studied, as well as its correction by nootropic drugs: sodium hydroxy butyrate and nooglutil. Administration of 20% ethanol per os at a daily dose of 5 mg per kg during the entire period of pregnancy led to a significant decrease in basal and K(+)-evoked DA efflux. Hydroxy-butyrate and Nooglutil (50 and 25 mg per kg, subcutaneously, daily from the 8th to the 20th day of life) normalized these alterations in alcohol-exposed neonates, although their effects on the offsprings of non-alcoholized rats were opposite. The probable neurochemical targets of ethanol and nootropics are discussed.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1991

[Detection of nootropic activity indicated by acute inhibition of orientation reaction].

Exploratory locomotor activity was studied in the experiments on adult male mice. It was shown that routine nootropic drugs as well as newly synthesized nootropic compounds were able to facilitate the development of inhibition during one registration session. Inhibition may be used for revealing only selective nootropic drugs devoid of sedative and stimulating effects.

Animals↗
PubMed1990

[Preservation of plastic properties of synaptic transmission in long-lasting hippocampal slices under the effects of a peptide analog of piracetam, L-pGlu-D-Ala-NH2].

The tetanic stimulation of the Schaffer collaterals (SC) in rat hippocamp slices after 6 hrs in vitro conditions did not produce long-term potentiation (LTP) of the field response amplitude in the CA1 pyramidal cell layer. In contrast, LTP after the late tetanization was well preserved in the slices that were perfused for 20 minutes with 0.5 mkM L-pGlu-D-Ala-NH2 (PGAA) after 4-4.5 hrs in vitro. There were no significant reactivity changes during the perfusion of the slices with this drug concentration. Two other drugs with nootropic activity, piracetam (100 mkM) and gamma-hydroxybutyrate (100 mkM, Na-salt) did not prevent the disappearance of LTP in the late period in vitro, while enhanced the reactivity during perfusion period. The maintenance of the plastic properties of the SC-CA1 synaptic transmission under the influence of PGAA is thought to be the result of some specific interaction of the drug with LTP induction mechanisms. LTP damaged in the late period in vitro might be a new model of memory disturbances and this model can turn out to be useful for the comparative estimation of the effectiveness of the drugs with proposed nootropic activity and for the analysis of the possible mechanisms of their action.

Animals↗
PubMed1990

[L-pyroglutamyl-D-alanine amide normalizes the function of the developing brain damaged by antenatal alcoholization in rats].

The effects of the synthetic dipeptide, L-pyroglutamyl-D-alaninamide (LPDA) were studied in the experiments on offspring of alcoholized during the pregnancy (5 g/kg/day) females. This dipeptide, which revealed the nootropic activity in previous experiments, was injected to the pups in dose of 1 mg/kg from 8 to 19 days of life. LPDA was shown to prevent the delayed disturbances of learning in passive avoidance test, of extrapolatory behaviour in escape test, to attenuate the emotional hyperreactivity. LPDA normalized EEG power spectrum, decreased interhemispheric asymmetry. This substance attenuated the disbalance evoked by prenatal alcoholization.

Age Factors↗
PubMed1988

[Normalization of the adaptive avoidance reaction in rats using substances with nootropic activity].

The system of double coaxial cylinders filled with water was used as a device for studying simple extrapolation behaviour of rats. The amount of rats which were able to dive under the lower edge of the inner cylinder, without reaching the bottom of the outer cylinder and the latency of this avoidance reaction were considered as a measure of extrapolation ability. This reaction was altered by the pretreatment of animals with cycloheximide, a protein synthesis inhibitor. Piracetam as a standard nootropic, sodium and lithium hydroxybutyrate as substances with a potential nootropic effect were shown to be able to antagonize the damaging effect of cycloheximide on the avoidance performance. Benzodiazepine tranquilizer, phenazepam, in contrast to nootropics, evokes additional worsening of extrapolation reaction. Normalization of avoidance disturbed by cycloheximide, can be used as an adequate and informative approach for screening of nootropics.

Adaptation, Physiological↗
PubMed1987

[Effect of piracetam on the habituation of the neuronal cholinoreceptor membrane of the edible snail].

Piracetam is shown to modulate the habituation pattern of cholinoreceptor neuronal membrane in Helix lucorum. Piracetam (10(-2) M) intensified the reversible decrease of depolarization and spike discharge induced by the local microionophoretic rhythmical application of acetylcholine to the neuron soma. The ability of piracetam to intensify the habituation of neuronal cholinoreceptor membrane may serve as a model of its facilitating effect on the development of habituation of behavioural reactions. Piracetam (5.10(-2) M) was shown to induce a shift in the membrane potential towards depolarization in the majority of identified neurons studied.

Acetylcholine↗