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Z D Pigareva

Publications and source records attributed to Z D Pigareva.

9 recordsLinked to original sources
PubMed1976

[Biochemical correlates of functional features of visual cortex neurons].

Changes of protein concentration and of different metabolic ferments activity were studied in the rabbit visual cortex after visual deprivation. Two groups of neurons with different sensitivity to visual deprivation were found. The less sensitive are supposed to have an additional source of activation. These findings corroborate the microelectrode data showing that the activity of about 40% of the visual cortex neurons are modulated by a different nonvisual stimulus.

Acetylcholinesterase↗
PubMed1976

[Cytochemical indices of intercentral interrelations of the motor and visual analyzers during light deprivation].

The authors used the interferometrical method to determine the content and concentration of the proteins in the neuron cytoplasma of the III and V layer in the motor and visual areas of the brain cortex in rabbits in normal conditions and prolonged light deprivation (from the moment of birth up to 2 1/2 months). These data were accompanied by measurements of the neuron area. It was demonstrated that the absence of visual impulses leads to a morphochemical underdevelopment of the neurons in the visual cortex layers. Such underdevelopment was expressed in a decrease in the size of the neurons and protein content in the cytoplasma compared to the control group. In the neurons of the III and V layer of the motor cortex of the same animals there were changes of a compensatory character (an increase in the size of the neurons, content and concentration of proteins in the cytoplasma). In this respect the authors discuss the question of the influence of specific visual and other forms of impulsation on the morphochemical differentiation of neurons in the studied brain cortex.

Animals↗
PubMedDate not supplied

[Effect of early visual deprivation on the free amino acid and protein content in the brain formations of dogs].

10 days old dogs were subjected to bilateral enucleation of eyeballs. When the dogs became 3 months old, content of free amino acids and total proteins was determined in tissue of brain formation of optic system (optic cortex-field 17, external knee body and front bigeminal bodies). locomotor and partietal regions of brain cortex and cerebellum. As compared with the control group, the amount of proteins was distinctly decreased in optic cortex and increased in external knee body. In all he brain formations studied content of arginine, lysine, gamma-aminobutyric acid, cysteine (except of external knee body) and histidine (except of external knee body and front bigeminal bodies) was distinctly increased. The decrease in content of glutamic acid was observed only in front bigeminal bodies and aspartic acid -- in cerebellum. Glutathione was accumulated selectively in front bigeminal bodies and in locomotor cortex.

Age Factors↗
PubMedDate not supplied

[Neurophysiologic and biochemical aspects of visual system development in the rabbit under conditions of photic deprivation].

Changes in the functional state of the visual cortex were studied by behavioral and electrophysiological cues and the chemism of its neurones at the cellular and subcellular levels in rabbits raised for one to two months in the dark. It has been shown that visual deprivation leads to retarded dynamics of elaboration and consolidation of the conditioned defensive reflex to light and to changes of opposite signs of the visual cortex surface EPs to specific and non-specific stimuli. Typical of the EPs to photic stimuli is a considerable decrease in amplitude and longer latency as compared with normal, and enhanced amplitude and shorter latency to acoustic stimuli. It has been cytochemically established that about half of the pyramidal neurones of the visual cortex layer V of the experimental animals display features of biochemical underdevelopment (of the size of the cytoplasmatic mass, the protein reserve). Under the same conditions activity depression was revealed in cytochromoxydase, Na, P-ATPhase and ACHE, expressed to a different degree in separate subcellular fractions of the visual cortex. The MAO activity selectively augments in the subfraction of cholinergic synaptosomes. It has been assumed that functional and biochemical changes in different groups of the visual cortex neurones due to deprivation are linked with both the properties of the synaptic structures in regard to perception of impulses of different modalities and the peculiarities of their chemism.

Animals↗
PubMedDate not supplied

[Mitochondrial energy processes of the visual system in the rabbit brain normally and under conditions of light deprivation].

A rate of endogenous respiration in mitochondria of rabbit brain visual system (visual cortex, forebrain) was higher under conditions of light deprivation (from birth up to 2.5 month) as compared with the mitochondria of control animals. The mitochondria of experimental rabbits were characterized by distinct alteration in oxidative phosphorylation of glutamic acid, by an increased rate of electron transport at the step between cytochrome c-cytochrome oxidase-succinate dehydrogenase of the respiratory chain as well as by the peculiar effect of rothenone and DNP on the chain. All the patterns studied approached the control value within the period of restoration of light impulsation. Nonlinear type of the regenerating processes was observed. Role of specific impulsation and compensatory reactions in the age-dependent development of energy processes in brain mitochondria is discussed.

Animals↗
PubMedDate not supplied

[Effect of early visual deprivation on glutamate decarboxylase activity in the visual analyzer of the brain].

Early vision deprivation decreased in dogs (45-days age) the activity of glutamate decarboxylase in all the structures of brain visual analyzer studied as well as decreased the enzyme activation by exogenous pyridoxal-5-phosphate. With areing (in 90-days old dogs) the deprivation proved to be less effective in relation to decrease in the glutamate decarboxylase activity in external geniculate body but caused the same affect in the visual zone of brain cortex and in anterior mesencephalon. The deprivation exhibited similar effect on formation of asparaginic acid.

Age Factors↗