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L B Verbitskaia

Publications and source records attributed to L B Verbitskaia.

18 recordsLinked to original sources
PubMed1989

[Effect of vascular factors and aging on the ultrastructure of neurons of the human cerebral cortex].

Neuronal ultrastructure of the frontal and temporal cerebral cortex has been studied in persons 36-, 39-, 50-, 70-year-old, died from the ischemic heart disease and 73-, 83-year-old, whose deaths are not connected with vascular pathology. The neurons can be divided into several groups, depending on osmiophilic degree of their nucleus and cytoplasm: I--electron-light, II--electron-opaque, III--with dark nucleus and light cytoplasm and IV--with light nucleus and dark cytoplasm. The protein-synthesizing apparatus (PSA) is subjected to the earliest and most essential disorders. Its changes in the I group of neurons at the age of 36-50 years are mainly of compensatory-adaptive character, while at the age of 73 and 83 years the dystrophic changes of the PSA result in hollowness of the cell, that evidently makes the base of the cell ageing mechanism. Presence of electron opaque neurons is not a sign of ageing, and depends on various pathology, in the given case on the ischemic heart disease, that causes certain vascular disorders in the brain. Variability of the ultrastructures of the electron opaque neurons and essential changes of some part of them, observed in the brain of the 72-year-old man confirm that the vascular factor is an important one in pathology of neurons. Dependence of lipofuscin appearance in neurons on the manifestation degree of the pathological process and ageing in them is discussed.

Adult↗
PubMed1988

[Compensatory-adaptive restructuring of the aging human brain].

In semithin sections of the frontal and temporal cortex from the human brains the compensatory-adaptive changes of neurons and glia were studied. The specimens were obtained from 2 physiologically aged subjects, 7 cases of senile dementia, 2 cases of Alzheimer disease. Alongside with the destructive changes in nerve and glial cells, the compensatory-adaptive processes were detected in aging brains, generally characteristic of the physiologic aging: the nucleolus shift to the nucleus periphery; redistribution of the nuclear chromatin, nuclear membrane invagination; closer attraction of the organelles to nuclear membrane as destruction increased; assembling the neural and glial cells; establishment of the desmosome-like glioglial contacts.

Adaptation, Physiological↗
PubMed1988

[Intracellular regeneration of neurons in the rat lateral hypothalamic area of the brain after resumption of food intake].

Electron microscopy was used to explore changes in intracellular regeneration processes in neurons of the anterior, medial and posterior parts of the lateral hypothalamus area (LHA) of rats at various time (10, 20, 30, 50 and 70 days) after resumption of food perception. Ultrastructural changes observed during 7 days of food deprivation in intact neurons were of a reversible character. Recovery processes initially appeared and finished earlier in the neurons of medial (day 30) and anterior (day 50) parts of the LHA, in the posterior part of LHA the normalization of the neuronal structure was slower and was over only by the 70th day after the resumption of food reception. The above data are both of theoretical and practical importance, serving as a base for the study of directed treatment of diseases caused by hunger.

Animals↗
PubMed1987

[Synaptic changes in cortical and subcortical brain formations in old rats].

Electron microscopy was used to study structural changes of synapses in sensorimotor, parietal, limbic cortical areas, hippocamp, blue spot and hypothalamus of old Wistar rats, aged 28-30 months. Polymorphism of ultrastructural changes in neuronal and synapse processes and individual variability of these shifts in the brain of old rats have been revealed. The predominant damage of post-synaptic synapse components with ageing is demonstrated. Along with dystrophic and destructive changes in pre- and post-synaptic parts of the contact, signs of compensatory adaptive resettings in inter-neuronal links have been detected.

Aging↗
PubMed1986

[Changes in neurons of the cerebral cortex in senile dementia].

Using light and electron microscopy, the frontal, temporal and parietal cortical neurons were studied in 10 cases of senile dementia. It was found that along with general age-specific disorders of the ultrastructure of neurons and glial cells (varying degrees of chromatolysis, accumulation of lipofuscin, mitochondrial changes) the examination revealed ultrastructural shifts which might be characteristic of senile dementia. They include rearrangement of nuclear chromatin, destruction of nuclear membrane with the subsequent vacuolization of the nucleus and karyolysis, the appearance of polymorphic fibrillar inclusions in the cytoplasm of neurons and gliocytes, as well as the disappearance of subsuperficial cysterns. Destructive processes were also attended by signs of compensatory changes, i.e. displacement of the nucleolus to the nuclear periphery, the development of desmosomophide contacts at the site of the neuron and glial satellite cell contact, the grouping of cells, and frequent fusion of the adjacent cellular elements.

Aged↗
PubMed1986

[Ultrastructural changes in the dendrites during aging].

Dendrite ultrastructure was studied in different brain areas of old rats, aged 28-30 months. Different ultrastructural forms of the reactive and destructive processes in the dendrites, irregularity of their pathomorphological changes with ageing and greater destruction of large dendrites, as compared to small ones are demonstrated.

Aging↗
PubMed1978

[Changes in neurons of a spinal ganglion culture during chronic exposure to increasing concentrations of morphine].

On the model of spinal ganglion cultures in mice by means of a light and electron microscopy the authors studied neuron changes in chronic influence of increasing concentrations of morphine. These studies demonstrated changes in most of the cytoplasmatic organells: changes in the granular and agranular reticulum; an appearance of a large amount of small vesicles in the cytoplasma and lysosome; changes of the mitochondria (partial vacuolization of the crysts and appearance of a big amount of small mitochondria); a large amount of myelin-like structures; changes of the nuclear membranes; nucleoli and an increased amount of ribosomes.

Animals↗
PubMed1978

[Postnatal histogenesis and cell proliferation in the parietal region of mouse neocortex under normal conditions and following brain injury].

Postnatal histogenesis of the parietal area of the neocortex and proliferative capacity in it of the main cell types were studied in mice under normal conditions and in stab wound of the brain by analysing 3H-thymidine-labeled cells on semithin sections. As revealed, microneurons failed to form in the parietal cortex of mice during the postnatal period either by migration of undifferentiated cells or by proliferation. Injury of the right hemisphere did not cause any change in the way of histogenetic transformations of cells migrating into the cortex of the parietal area in the direction of their differentiation into microneurons.

Animals↗
PubMed1977

[Interaction of fibers from the retina and visual region of the cortex in several subcortical visual formations of rats].

The medial nucleus of the optic tract, the ventral lateral geniculate nucleus and the superior colliculus have been studied using the light (Nissl, Golgi, Viktorov) and electron microscopic methods in normal rats and in rats which survived for different periods after enucleation or occipital cortical lesions. Data were obtained on differences in terminal patterns of the afferent pathways. The study of the neuronal and synaptic organization of subcortical visual centers showed the distinctions and correlation between the complexity of neuronal and synaptic organization. Three types of interrelations between the optic and cortical pathways on the efferent neurons of the investigated structures are suggested.

Animals↗
PubMed1976

[Cytoarchitectonics of the vestibular nucleic of the brain of the dolphin (Delphinus delphis)].

Specific features of the structure of the vestibular complex of Cetaceans correlating with specific features of the structural functional organization of these representatives of aquatic mammals were detected in a cytoarchitectonic investigation of the topography and strucutral organization of nuclei of the vestibular complex performed in Delphinus delphis and compared with the organization of the corresponding structures of the brain of man and chimpanzee.

Animals↗
PubMedDate not supplied

[Ultrastructural changes in neurons of the arcuate nucleus-median eminence complex in rats irradiated with carbon ions and gamma rays].

Ultrastructural changes in the arcuate nucleus and medial eminence area of rats were examined 5 weeks after their exposure to accelerated carbon ions with an energy of 300 MeV/nuclon and 60Co gamma-rays at a dose of 2.0 Gy. In carbon-irradiated animals the ultrastructural changes of arcuate nucleus neurons, their processes and synapses were more significant and diversified than in gamma-irradiated rats.

Animals↗
PubMedDate not supplied

[Ultrastructural changes in the rat cerebellar cortex in the remote periods after exposure to accelerated carbon ions].

The cerebellar cortex of rats irradiated with carbon ion fluxes of 320 Mev/nuclon and 60Co gamma-radiation was examined by light and electron microscopy 1, 3 or 6 months after exposure. Carbon ions induced the greatest pathomorphological changes. A month after exposure the changes were diffuse and reversible while 3 and, especially, 6 months after irradiation they were focal disorders, a large portion of which being irreversible. 3 and 6 months after exposure some structures of the cerebellar cortex showed destructive while others exhibited reparative changes. Structural disorders in various nerve and glial cells were of different type. Disorders of the Purkinje cells were of the dark type and those of adjacent Bergmann glial cells of the light type. In the granular layer, neurons showed light type changes and adjacent oligodendrocytes, a densely packed karyo- and cytoplasm and a higher osmiophilia. It can be assumed that the above changes are to maintain disordered neuronal functions, including cell interactions. Study of time course variations in the neuronal and glial ultrastructure of the cerebellar cortex of irradiated animals shows an increase of destructive changes with time. This investigation has demonstrated that CNS cells may be damaged long after exposure even to small fluxes of heavy charged particles.

Animals↗