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V S Lushchekin

Publications and source records attributed to V S Lushchekin.

13 recordsLinked to original sources
PubMed1991

[The morphometric characteristics of the neurons of the reticular nuclei in the brain stem in the kitten].

In the brain stem of 30-day-old kittens three types of Golgi-stained neurons are distinguished: sparsely branched reticular neurons, densely branched arborescent neurons and multipolar giant neurons (according to the classification by Leontovich). Implication of the new method of computer morphometry permits obtaining formalized characteristics of 23 parameters of the above types of neurons. An analysis of the quantitative characteristics of the studied neurons has revealed statistically significant differences in most parameters. This fact permits advancing a conclusion about morphological identity (stability) of each type of the neurons. Structural differences and similarities in reticular nuclei are discussed with respect to their functional features.

Animals↗
PubMed1991

[The effect of sectioning the lingual nerve on the morphometric characteristics of the reticular nuclei in the brain stem in the kitten].

Three subpopulations of Golgi-stained neurons of the brainstem reticular nuclei have been studied by the method of computer morphometry in 30-day old kittens. 23 parameter of the neuronal geometry were analyzed after uni-and bilateral lingual nerve section 5-7 days after birth. All of cells display statistically valid changes in some parameters, typically differing in every group: for reticular neurons--free distribution of dendrite endings in the dendritic field; for arborescent ones--the length of dendritic segments; for giant multipolar neurons--distribution of foci of maximal dendrite branching in the dendritic field. Unilateral lingual nerve section gives more pronounced quantitative deviations from the normal state, than bilateral one.

Animals↗
PubMed1990

[The structural characteristics of the dendritic apparatus of transplanted neurons from the embryonic amygdala].

Two main neuronal classes were studied in the grafts of basolateral nucleus of the rat embryonic amygdala stained by the Golgi method--sparsely and densely ramified cells. Transplantation resulted in the increase of dendrite length and ramification of sparsely ramified cells, in the decrease of cell body size and increase of ramification of densely ramified cells. The analysis of polar histograms of the dendritic orientation shows the selective increase of dendrite length and ramification of the both neuronal classes. The dendrites of the intact neurons of basolateral amygdala are distributed almost regularly, they do not display any dominant orientation. After transplantation the main orientation to the area of graft-host integration appears. The changes in dendrites are discussed with respect to the ability of the graft to take part in compensation of the damaged brain functions.

Amygdala↗
PubMedDate not supplied

Features of the establishment of the spontaneous activity of neurons of the trigeminal sensory nuclei of viable sections of the rat brainstem in postnatal ontogenesis.

An attempt was made to characterize the features of the development of the neurons of the sensory trigeminal nuclei, a basic structure of the sensory support of alimentary behavior, in the late stages of postnatal ontogenesis. A technique involving viable sections of the brainstem of infant rats at the ages of two, four, and eight weeks was utilized. An increase with age in the number of neurons possessing spontaneous activity (44% at two weeks; 69% at eight weeks), an increase in the frequency of discharges, the appearance by the fourth week of a population of cells with high-frequency spontaneous activity, and an increase in the number of such neurons by the eighth week. Three types of background-active neurons were distinguished: episodic, continuous, and group; and the dynamics of the change in the ratios of these types with age was demonstrated. Significant changes with age were not found in resting potentials, although a tendency to its increase takes place between the second and eighth weeks of postnatal development.

Aging↗
PubMedDate not supplied

[The characteristics of the formation of spontaneous neuronal activity in the trigeminal sensory nuclei of surviving slices of rat brain stem in postnatal ontogeny].

An attempt was made to characterize the development of neurones of sensory trigeminal nuclei--basic structure of sensory provision of alimentary behaviour at late stages of postnatal ontogenesis. The method of the brain-stem slices of rat pups [correction of ratlings] aged 2.4 and 8 weeks was applied. An increase with the age was shown of the number of neurones with spontaneous activity (44%-2 weeks; 69%-8 weeks), growth of discharges frequency, appearance of cells population with high-frequency spontaneous activity by the fourth week and an increase of such neurones number by the eighth week. Three types of background-active neurones were singled out: episodic, continuous and group; the dynamics of correlations change of these types with the age was shown. No significant changes of rest potential with the age were found, though there was a tendency to its increase between the 2-nd and 8-th weeks of postnatal development.

Aging↗
PubMedDate not supplied

[A comparison of the take of embryonic amygdala and visual cortex transplants in the rat brain in connection with the possible compensation of functional disorders].

Transplantation of embryonic (E17-18) visual cortex and amygdala was performed into corresponding damaged areas of the adult rat brain. It was shown in Nissl and Golgi preparations (by comparing qualitative and quantitative findings) that 2-6 months after operation the grafts were successful in case of putting them into the corresponding brain areas (cortex to cortex, or amygdala to amygdala). Graft's integration resulted in a selective increase of dendrite length and ramification towards the area of graft-host interface both in amygdala and visual cortex grafts. In case of inadequate graft-host integration the stratification of the grafted visual cortex could be observed. The structural reorganization of grafted neurones is compared with physiological and behavioural findings during the recovery processes in damaged brain.

Amygdala↗
PubMedDate not supplied

[Organization of early forms of kitten behavior after partial oral deprivation].

Study of development of early forms of behaviour was carried out on intact kittens of the first month of life, who endured in 5 days age uni- and bilateral sections of the lingual nerve, and on shame-operated and undernourished animals. It was shown that bilateral deafferentation caused significant disturbance of alimentary behaviour at the stage of sucking, manifested in disturbance of natural sucking and appearance of shame sucking, i.e. rhythmic sucking movement without nipple grasping. At the one-month age, in conditions of artificial feeding, natural sucking in operated animals was restored and the shame one disappeared. Bilateral section of the lingual nerve led to acceleration of ripening of sensory and motor systems and accelerated development of homing, exploratory and playing behaviour. Possible role is discussed of sensory trigeminal nuclei neurones in organization of normal patterned sucking and at limited sensory inflow. It is suggested that elimination of sensory input developing in the norm earlier than others, changes natural terms of other channels development, what accelerates the change of early behaviour forms.

Aging↗
PubMedDate not supplied

[Role of species-specific acoustic signals in the "homing" orientation of intact and olfactory deprived kittens].

Vocal responses of lactating cats were recorded and used to investigate home orientation in 1-30 days old kittens. Two types of species-specific acoustic signals were chosen and used in acoustically-guided homing. Type 1 comprised fricative signals below 1.5 kHz of low intensity and long duration. Type 2 comprised intense tonal calls with 2-4 resonant frequency components below 4 kHz. Presentation of tape-recorded signals 1 and 2 through the speaker placed into the home site increased the ability of the kittens to return to the nest. Zn-induced anosmia eliminated home orientation. Presenting of the signals 1 and 2 to anosmic kittens resulted in the recovery of homing. Acoustically-guided behaviour first appears at 6-9 days of age and fully matures by 25-30 days.

Age Factors↗