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N I Dmitrieva

Publications and source records attributed to N I Dmitrieva.

At least 37 records · Page 2Linked to original sources
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[The behavioral and neuromorphological characteristics of rats with spontaneous hypertension].

Rats with spontaneous hypertension (strain SHR) reveal retarded somatic growth at early stages of ontogenesis. However, in further postnatal life, after transition to self-feeding, these animals exhibit larger body mass. Significant correlation was found between the arterial pressure and body mass. Some peculiarities in the behaviour of rats from the strain SHR were found already at early stages of ontogenesis. In 2-month animals, the brain exhibits some unusual features: lateral ventricles are enlarged, the corpus callosum is thinner, the volume of the pyramids in the dorsal hippocamp (field CA3) is less than in normal rats, the structure of the lateral hypothalamus being also different. It is suggested that unusual behaviour of hypertensive strain is due to the observed structural differences, as well as to changes in noradrenergic system of the brain.

Aging↗
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[Morphometric and electrophysiologic research on the parafascicular complex of the thalamus in early ontogeny in the rabbit].

Electrophysiological, morphometric and behavioural studies have been made on the role of parafascicular complex in regulation of nociceptive sensitivity in 45 rabbits from the 1st to the 16th day of their postnatal life. The evoked potential to nociceptive stimulation was recorded already in 1-day animals. Analysis of amplitude-temporal parameters of the EPs in acute experiments revealed a sharp increase in their positive phase at the 7-8th day of life. As it was shown in the behavioural experiments, that is just the period of maximum generalized reaction to nociceptive stimulation. It was found that to this age, the surface of neurones in the complex significantly increases, their density remaining still high. The data obtained are discussed in relation to factors which account for ontogenetic changes in electrophysiological correlates of neuronal responses in the parafascicular complex to peripheral nociceptive stimulation.

Aging↗
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[Structural characteristics of the hippocampus in various strains of rats and mice].

Original data together with those from literature are presented concerning structural peculiarities of the hippocamp in rats and mice. Structural differences are revealed not only in these species, but in separate strains from a single species. Fine structural differences may account for different modes of realization of the behavioural reaction.

Animals↗
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[The features of the hippocampal structure as a neuroanatomical basis for differences in behavior].

Neuromorphological and behavioural studies have been made on several strains of mice (C57B1, DBA/2, SEC) and on the spiny mouse Acomys cahirinus. It was shown that animals with different genotypes differ by the size of fascia dentata and by the extension of the pyramidal layer in CA3 field of the hippocamp. Animals with a higher learning capacity exhibited smaller layer of granular cells in the fascia dentata, which may be due to a lower density of neurones in this region. Terminals of the mossy fibers--the axons of granular cells--were found mainly on the apical dendrites of the pyramidal cells in CA3 field. On the contrary, in animals with lower capacities to learning, mossy fiber terminals were observed mainly on the basal dendrites of the pyramidal cells, the extent of the granular layer in these animals being significantly larger.

Animals↗
PubMedDate not supplied

[Effect of hippocampal damage on the appearance of trace reactions in dogs during ontogenesis].

The formation of trace motor and secretory alimentary conditioned reflexes were studied in dogs after injury of dorsal part of hippocampus at different stages of ontogenesis, 38--42 days, 3, 5, and 13 months. All animals with lesioned dorsal hippocampus formed non-delayed motor and secretory reflexes. Trace motor reflexes were elaborated in four out of nine animals, and trace secretory ones--only in one animal. The experiment emphasized the importance of the degree of hippocampal injury for the maintenance of the studied functions. Morphological analysis revealed that degeneration of thalamic nuclei is identical in animals operated at different age. No signs of brain tissue regeneration were observed.

Animals↗
PubMedDate not supplied

[The role of protein kinase C and muscarinic cholinoreceptors in vasopressin-stimulated water transport].

The role of protein kinase C (PKC) in the control of vasopressin-stimulated water transport in the frog urinary bladder and its modulation by M2-agonist oxotremorine has been studied. Using the PKC inhibitor, staurosporine we showed that PKC in the region pf the basal membrane suppressed vasopressin-stimulated water transport, whereas PKC in the apical region potentiated this transport. It was also found that from the two types of oxotremorine action on stimulated water transport determined by its concentration only inhibition is mediated through PKC.

Alkaloids↗
PubMedDate not supplied

[Morphofunctional parameters of the thyroid gland in late periods after prolonged stress in rat strains selected for nervous system excitability].

Thyroid morphology, function, and hormonal levels were studied in two rat strains with genetically determined levels of nervous system excitability immediately and in late periods after prolonged stress resulting in development of a neurosis-like state. A high resistance of the linear characteristics of thyroid morphology and function was revealed whose high functional activity was observed in the rats with a low excitability threshold. Two weeks after neurotization cessation morphofunctional status of the thyroid normalized.

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