[The distribution of aspartate aminotransferase activity in the structures of the visual analyzer in the canine brain during postnatal ontogeny]. / Raspredelenie aspartataminotransferaznoi aktivnosti v strukturakh zritel'nogo analizatora mozga sobak v period postnatal'nogo ontogeneza.

Studies have been made on aspartate aminotransferase activity in light and heavy synaptosomes, membrane and synaptic mitochondria from the visual cortex (field 17), bigeminal bodies, and outer geniculate body. It was shown that the enzymic activity significantly decreases in all the subfractions investigated in puppies beginning from 6 months up to 1 year. In earlier postnatal ontogenesis, the activity increased in all the subfractions, the extent of the increase being dependent on the source of the enzyme.

[The activity of Krebs cycle enzymes in the visual analyzer of normal rats and under stress]. / Aktivnost' fermentov tsikla Krebsa v zritel'nom analizatore krys v norme i pri stresse.

In the visual analyzer of the intact animals higher activity of NAD-dependent dehydrogenases of tricarbonic acids cycle is observed in the retina and of FAD-dependent dehydrogenases in the occipital brain lobes. The influence of stress by Desiderato method elicits compensatory increase of the succinatedegidrogenase activity. The acute stress elicits a change of regulation of the activity of dehydrogenase of tricarbonic acids cycle, estimated by the reaction to functional load. Animals staying in the darkness after stress promotes restoration of the tricarbonic acids cycle of the enzymes activity up to the normal level.

[Subcellular changes in the cortex of the motor analyzer and hippocampus of dogs with locally manifested neuroses]. / Subkletochnye izmeneniia v kore dvigatel'nogo analizatora i gippokampa sobak pri nevroze s lokal'nym proiavleniem.

In experiments on dogs with local neurosis-continuous flexion of the foreleg-changes were revealed in the beta-rhythm amplitude and the frequency of mean unit activity in the motor cortex, and the appearance and increased amplitude of the theta-rhythm in the hippocampus. Specific activity of Na+-K+-activated, and Mg2+-dependent ATPase decreases in subcortical fractions of the experimental animals' cerebral cortex by 55.0% in the synaptic membranes and 2 to 2.5 times in light and heavy synaptosomes, respectively. In similar fractions of the dorsal hippocampus, the activity of the enzyme decreases by 30.0% in the synaptic membranes and increases by 16.6% in the light synaptosomes and by 6.6% in the heavy ones.

[GABA-transaminase activity in the dog brain visual analyzer following light deprivation during ontogenesis]. / GAMK-transaminaznaia aktivnost' v zritel'nom analizatore mozga sobak pri svetovoi deprivatsii v ontogeneze.

The GABA-transaminase activity is the highest in the subcortical formations of the brain visual analyzer in 45- and 90-day dogs. Deprivation of visual impulses at early stages of postnatal ontogenesis lowers sharply this activity in all the studied areas of the brain visual analyzer. Under conditions of deprivation the content of glutaminic acid increases in all the formations of the dog brain visual analyzer to a considerably less extent, especially in the anterior corpora bigemina and lateral geniculate body at the age of 45- and 90-days. Similar regularities are found in the deprivation effect relative to formation of ascorbic acid the content of which lowers sharply in all the formations of the dog brain visual analyzer on the 90th day of light deprivation.

[Several biochemical signs of loss and restoration of visual function]. / O nekotorykh biokhimicheskikh priznakakh utraty i vosstanovleniia zritel'noi funktsii

With the aid of cytophotometry the author studied the cellular chemistry of neurons (according to the activity of glutamate dehydrogenase) in the III, IV and V layers of the visual cortex in rats during the period of rehabilitation of specific functions following long-term light deprivation. It was demonstrated that a 2-week stay of deprivated animals in conditions of usual light is accompanied by visible normalization of the glutamate dehydrogenase activity in the cortical neurons. However, a complete rehabilitation of the control level was not attained. The study demonstrated differences in the reactions of identical neurons in the IV and V layers to the rehabilitation of specific functions. It is being assumed that the rehabilitation of the visual function may be due to biochemical reconstructions in the monomodel and certain parts of the polymodal neurons in the visual cortex.