[L-pyroglutamyl-D-alanine amide normalizes the function of the developing brain damaged by antenatal alcoholization in rats]. / Normalizatsiia amido L-piroglutamil-D-alanina funktsii razvivaiushchegosia mozga, narushennykh antenatal'noi alkogolizatsiei krys.

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.

[Normalization of the adaptive avoidance reaction in rats using substances with nootropic activity]. / Normalizatsiia adaptivnoi reaktsii izbavleniia u krys veshchestvami s nootropnoi aktivnost'iu.

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.

[Possible mechanism of the activating action of GABA-positive substances]. / O vozmozhnom mekhanizme aktiviruiushchego deistviia GAMK-pozitivnykh veshchestv.

The effects of high and low doses of GABA-positive drugs (muscimol, depakine) and a tranquillizer diazepam on behavioral and electrophysiological indices were studied. The depressant effect of high doses and the activating one of low doses of the studied agents were shown. It was concluded that the activating effect of GABA-positive drugs reflects the activity of the disinhibitory system, that is, the group of interneurons suppressing the activity of inhibitory neurons. GABA seems to be a transmitter in the disinhibitory system.

[Sodium oxybutyrate correction of the disorders in higher nervous activity in the progeny of alcoholized animals]. / Korrektsiia natriia oksibutiratom narushenii vysshei nervnoi deiatel'nosti potomstva alkogolizirovannykh zhivotnykh.

Alcoholization of female rats before pregnancy (8 g/kg) or during pregnancy (4 g/kg) leads to disturbances in the development of the offspring higher nervous activity manifested by impaired learning abilities, disordered emotional reactivity, reduced capacity to overcome stress-situation, deficit of GABAergic inhibitory processes in the cerebral cortex. An early postnatal administration of sodium hydroxybutyrate in a dose of 50 mg/kg prevents the development of the above mentioned disturbances of the higher nervous activity and neurophysiological alterations.

[Normalizing effect of GABA derivatives on late behavioral disorders occurring in rats with early postnatal suppression of protein synthesis]. / Normalizuiushchee vliianie proizvodnykh GAMK na otdalennye narusheniia povedeniia, voznikaiushchie u krys pri rannem postnatalnom ugnetenii belkovogo sinteza.

Changes in the central nervous system activity caused by an early postnatal (7th day of life) injection of cycloheximide (CHX) were studied during experiments on adult rats. Disturbances in the process of learning in the experiments on conditioned reflexes of active and passive avoidance, difficulties in solving the extrapolatory task, weakening of habituation, motor hyperactivity, disorder of movement coordination were noted. Electrophysiological analysis by means of evoked potential recovery cycles revealed deficiency of GABAergic inhibition in the cerebral cortex. Hydroxybutyric salts of sodium and lithium as well as piracetam injected after CHX (from 8th through 14th days of life) normalized general behavior and learning capability of adult rats. Phenibut (beta-phenyl-GABA) was inferior by its efficacy, GABA exhibited no distinct effect.