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V P Babmindra

Publications and source records attributed to V P Babmindra.

At least 19 recordsLinked to original sources
PubMed1979

[Morphofunctional interrelationships between the hippocampus and hypothalamus in rats].

Evoked reactions of the hypothalamic arcuate and medial preoptic nuclei neurons were recorded when the hippocampus was stimulated by single stimuli in anaesthetized rats. In the arcuate nucleus phasic responses and primary inhibition were found to be dominant and in the medial preoptic nucleus--both phasic and nonspecifical responses. After injection of the horseradish peroxidase into the stimulated hippocampal region stained cells were found in the nuclei of the mammillary complex, mediobasal hypothalamus and in the medial preoptic nucleus. Groups of stained neurons were observed in the periphery of ventro- and dorsomedial, lateral and mammillary nuclei of the hypothalamus. In all the studied structures, except the medial mammillary nucleus, reticular-like cells were found alongside with spindle-like and triangle neurons. The data obtained are discussed in connection with the problem of hypothalamo-hippocampal interaction.

Animals↗
PubMed1979

[Horseradish peroxidase labeled neurons of the ventrobasal complex of the thalamus projecting to the somatosensory zone I of the cat cerebral cortex].

The morphology and topography of the neurons in the ventro-basal complex (VB) projecting to the somatic sensory cortex (SI) were studied by the method of the retrograde axonic transport of horseradish peroxidase (HRP). Different types of HRP-labelled cells were found in this structure. The concentration of labelled cells was the greatest in the central part of the VB. The most peculiar feature in the distribution of HRP-positive neurons was their organization in two large populations in the dorsal and ventral portions of the VB. A comparison with the somatotopic map of the VB revealed that the central region of this complex is the area of the representation of the forelimb and the head. Our morphological results confirm the neurophysiological conception about the organization of the thalamo-cortical input on the "point-to-point" projection principles.

Animals↗
PubMed1978

Intracortical horizontal connections of neurons in cat and monkey motor cortex.

The present paper deals with the study of the structure of horizontal neuron chains, one of the aspects of intracortical intraneuronal relationships. The motor cortex (field 4) of cats and lower monkeys (Papio hamadryas and Macacus rhesus s. M. mullata) was treated by the impregnating method of Golgi--Kopsh. The drawings of neurons from 90-micrometer sections were made by means of a camera lucida. Three possible pathways of impulse transmission along neuron chains in a horizontal direction were revealed. These were: a pyramido-pyramidal system of connections which may possibly spread excitatory influence among several columns; a basket-pyramidal connection system; and connections which arise from successive switchings between neighboring neurons of one layer.

Animals↗
PubMed1978

[Dendritic spinules detected by the peroxidase method].

The structure of marked associative pyramidal neurons, their dendrites, and spines in layer III of somato-sensory cortex in cats after HRP-injection into the motor cortex has been described. Secondary and tertiary branches of basal dendrites are revealed more often than the apical ones. But the spines, especially their heads, were more obvious on the apical dendrites. The marked associative neurons are displaced sparsely, making no accumulations.

Animals↗
PubMed1977

[Cortico-cortical connections in the motor cortex of the brain; a study using the peroxidase method].

Using a method based on retrograde axonal transport of horse-radish peroxidase (HRP), the cortico-cortical afferents of the motor cortex were studied. After enzyme injection into the posterior sigmoideus gyrus, the HRP product was found in the first and the second somatic sensory areas and in parietal cortex (fields 5a, 5b). The HRP-positive neurons occurred in layers II, III and V of the cortex and belonged to the pyramidal cells.

Afferent Pathways↗
PubMed1977

[Structural characteristics of the mediodorsal nucleus of the cat thalamus].

By means of the light and electron microscopy, construction and architectonics of neurons in the cat thalamus medio-dorsal nucleus are described. Differences in the neuronal body dimentions, their form, number of deferent dendrites and character of axonal branching made it possible to define 3 types of neurons. Applying the method based on retrograde axonal transport of exogenous horse-radish peroxidase, it was demonstrated that neurons of type II, contrary to the existing opinion, send their axons into the prefrontal cortex and, hence, are associative-projective. Ultrastructural difference of axonal terminals, differences in the form and size of synaptic vesicles made it possible to reveal 5 types of presynapses.

Animals↗
PubMed1976

Structure of neuronal assemblies in cerebral cortex.

Interrelations in the apical dendrite bundles of a single neuronal column were revealed by means of light and electron microscopy in the cat motor cortex. Such column presents an integrated structural module. There were also found wider joinings of several columns, among which complex coordination may exist.

Animals↗
PubMed1976

[Morphological studies on interneuronal relations in the feline motor cortex].

Three types of neuronal joinings in the cat motor cortex are described. The joinings of the 1st type (nests, barrels) consist of some pyramidal cells, apical dendrites of which form the bundles. The consolidation of neurons is achieved by means of dendro-dentritic contacts, pyramidal neuron collaterals and the associative transcortical afferents. The joinings of the 2nd type (distant) are formed with the participation of intracortical connections between the pyramidal and stellate neurons and are placed as concentric formation. The joinings of the 3rd type are formed with the help of projection thalamo-cortical afferents and large horizontal collaterals of basket cells.

Animals↗
PubMed1976

[Experience with the use of horseradish peroxidase for light and electron microscope studies of interneuronal connections].

By the method based on a retrograde axonal transport of exogenous horseradish peroxidase (HRP), the origins of afferentation of the motor cortex of adult cats, kittens and albino rats were studied. HRP-positive neurons were found by light and electron microscopy in the somatosensory cortex (C1) of the ipsilateral hemisphere and in the portions of the cortex of the contralateral hemisphere which were symmetrical to the site of injection of HRP. The disposition of neurons, marked by HRP, in the Vth layer of the motor cortex suggest that these neurons may send their axons into the bundles of comissural fibres going to the motor cortex of the opposite hemisphere. This method considerably expands possibilities of revealing the origins of afferentation of the investigated portion of the nervous system and allows more complete and reliable investigation of interneuronal connections.

Animals↗
PubMed1976

[United neurons in the cat motor cortex].

Vertically oriented bundles of apical dendrites in the cat motor cortex are described by means of light and electron microscopy. Existence of desmoidal and dendro-dendritic contacts in the bundles is considered as the structural basis of neuronal electrotonic interaction within the limits of one column. Sliding axo-spinal contacts are described between the descending pyramidal axon in layer III and the pyramidal apical dentrite in layer V which, probably, serve for the purpose of regulating activity of the main cortical output elements.

Animals↗
PubMed1975

[Ultrastructural characteristics of axon terminals of the posterior lateral nucleus of the thalamus in the cat].

Two kinds of axon terminals: fine M-terminals with the diameter up to 2 mkm and large K-terminals with the diameter up to 6 mkm were found in electron microscopic study of the posterior lateral nucleus of the cat's thalamus. M-terminals comprising 88% of the total amount of the axon terminations under analysis are characterized by a great amount of densely packed light round synaptic vesicles and solitary mitochondria. These terminals form asymmetrical type of contacts in which the post-synaptic network is distinguished with a high degree of osmiophilia. The K-terminals contain a few rarely distributed round light synaptic vesicles and many mitochondria which are disposed in the central part of the termination. These terminals form a symmetrical type of synaptic contacts with poorly pronounced active zones in these formations. In axo-axonal contacts between the described kinds of terminals the K-terminals always serve as a presynapse. After extirpation of the sincipital cortex M-terminals underwent degeneration.

Animals↗