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O Narkiewicz

Publications and source records attributed to O Narkiewicz.

At least 19 recordsLinked to original sources
PubMed1992

Cytoarchitectonics of the nucleus of the lateral olfactory tract in the rat.

The cytoarchitectonics of the nucleus of the lateral olfactory tract (NLOT) was studied on Nissl stained sections in 6 brains of adult Wistar rats by using morphometric methods. The neuronal density of layer III (11,866 +/- 547 mm-3) is on average about three times smaller than that of layer II (30,947 +/- 1110 mm-3). The average cross-section area of neurons in layer III (254.3 +/- 3.8 microns2) is about twice as large as that of neurons in layer II (115.8 +/- 0.8 microns2). The layer II is rather homogenous in contrast to layer III which possesses neurons of various size. Other morphometric parameters of layer II and III are also different.

Animals↗
PubMed1990

Relation of the insular claustrum to the neocortex in Insectivora.

The claustra of 9 species of Insectivora (Sorex araneus, Sorex minutus, Tenrec ecaudatus, Solenodon paradoxus, Neomys fodiens, Erinaceus europaeus, Talpa europaea, Desmana moschata, Potamogale velox) were investigated. In all examined animals we found two parts of the insular claustrum: the main part called by us the pars principalis and more medially situated lamina profunda claustri. In the "basal" Insectivora the main part is in close contact with the layer VIa of the neocortex. In some more developed "basal" and in all "progressive" Insectivora the area capsularis appears. Dorsolaterally it separates the main part of the insular claustrum from the neocortex and possesses, besides neurons, also numerous fibers of the extreme capsule. The above data strongly suggest that in the phylogenesis the insular claustrum originates from the cortex from which it gets separated by the extreme capsule. Lamina profunda claustri is rather a narrow band of neurons situated on the medial side of the pars principalis and mostly separated from it by a thin lamina of white substance. Lamina profunda is continuous with the layer VIb of the neocortex.

Animals↗
PubMed1989

Nucleus limitans thalami--comparative anatomical study.

Cyto- and myeloarchitectonics as well as acetylcholinesterase activity of the nucleus limitans thalami--an important part of the nociceptive system--were studied in insectivora (Sorex araneus, Erinaceus europaeus, Talpa europaeus), rat, rabbit, cat, monkey and man. Our results suggest that nucleus limitans is phylogenetically a rather new structure. In insectivora and in the rat we could not find any evident group of neurons resembling nucleus limitans. In the rabbit and cat nucleus limitans is composed of few layers of elongated cells. In macaca and man it is a larger, more complicated structure possessing various types of neurons, and arranged into many layers.

Acetylcholinesterase↗
PubMed1987

Projections from the pretectothalamic border area to the somatosensory part of the claustrum: an autoradiographic study.

Injections of tritiated amino acid into the pretectothalamic border area of cats resulted in the appearance of numerous silver grains in the ipsilateral claustrum. The accumulation of grains was especially abundant in the dorsomedial area of the central part of the claustrum. These results indicate the presence of substantial projection from the pretectothalamic border area to the claustrum. It may be assumed that these projections belong to the somatosensory system, since they connect mainly di(mes)encephalic nuclei, receiving largely the somatosensory input, with the somatosensory part of the claustrum.

Amino Acids↗
PubMed1986

Neurons of the claustrum in the cat; a Golgi study.

The insular claustrum of the cat was studied using Kopsch modification of the Golgi technique. Neurons with or without dendritic spines were found. Among spiny neurons large pyramid-like cells with one main dendrite (S I type) appeared most frequently. Spindle-shaped neurons with two main dendrites (S II type) and multipolar ones (S III type) occurred much less frequently. Two types of aspimny multipolar neurons were found-larger (A I type) and smaller (A II type). Both were observed only in the posterior areas of the claustrum, mainly in its visual part. In the narrower regions of the claustrum, especialy in its anterior and posterior part, the dendritic fields of neurons were mostly arranged parallel to the surface of the claustrum. Centrally in the broader intermediate part of the claustrum long axes of neurons were oriented in various directions.

Animals↗
PubMed1984

Projections of the amygdaloid body to the insular cortex in the cat.

Experiments were performed on brains of 15 cats with the use of horseradish peroxidase (HRP) retrograde transport method. After injections of HRP to the insular cortex, relatively great numbers of labeled neurons were found in all main nuclei of the amygdaloid body. After injections to the anterior part of the granular insular cortex numerous labeled neurons were located in the lateral, central lateral, basal dorsal and basal ventral nucleus of the amygdaloid body. Injections to the agranular insular cortex labeled neurons in the lateral, basal dorsal and basal ventral nucleus and in the claustrum prepiriforme. These results indicate the presence of large projections from vast areas of the amygdaloid body to the agranular insular cortex and the anterior part of the granular insular cortex.

Amygdala↗
PubMed1981

Interamygdaloid connections in the rat studied by the horseradish peroxidase method.

Neurons of the rat amygdaloid body were labeled with horseradish peroxidase following its injection into contralateral nuclei of the amygdala. The results strongly suggest that there is a contralateral amygdaloid projection from the basal (dorsal and ventral) nuclei of amygdala; it terminates in the medial, central and lateral nucleus. True commissural connections were found only between posterior parts of the cortical nuclei of amygdala and between homonymous areas of the piriform cortex.

Amygdala↗
PubMed1981

The organization of intraamygdaloid connections; an HRP study.

The localization of neurons from which the projections to other amygdaloid nuclei arise was studied using the retrograde transport of horseradish peroxidase. It was found that the basal nuclei (dorsal and ventral) appear to be the main source of intraamygdaloid connections; they project to the central, medial and lateral nucleus of the amygdala. The medial and the central nucleus receive the most intraamygdaloid connections: the medial--from the basal dorsal, basal ventral, posterior part of the cortical nucleus and from the nucleus of the lateral olfactory tract; the central nucleus--from the basal (dorsal and ventral) nuclei and from the nucleus of the lateral olfactory tract. The afferent intraamygdaloid connections of the cortical and lateral nucleus were also found. These results are discussed with reference to the physiological differentiation and hypothalamic afferents of the amygdaloid body.

Afferent Pathways↗
PubMed1980

Tegmental afferents of the amygdaloid body in the rat.

Horseradish peroxidase (HRP) was injected to various parts of the amygdala in 50 rats. Retrograde axonal transport revealed that tegmental areas containing biogenic amines: dorsal and median raphe nuclei, locus coeruleus and ventral tegmental area, project diffusely to various amygdaloid areas. Moreover, HRP labeled cells were found in the parabrachial nucleus (following injection of the lateral amygdaloid nucleus) and in tegmental dorsolateral nucleus (after injection of the central nucleus of amygdala).

Amygdala↗
PubMed1979

Thalamoamygdaloid connections studied by the method of retrograde transport.

On the basis of retrograde horseradish peroxidase transport from nuclei ot the amygdaloid body of the rat to the thalamus, it was found that several groups of thalamic nuclei send fibers to the amygdala. These are: (i) nuclei of posterior region of thalamus and neighboring area of the tegmentum - peripeduncular nucleus, suprageniculate-limitans nucleus, (ii) midline nuclei - paraventricular nucleus, parataenial nucleus, nucleus reuniens, (ii) intralaminar nuclei - central medial nucleus, parafascicular nucleus, (iv) medidorsal nucleus. There are two main systems of thalamoamygdaloid connections. One of them arising in the posterior region of the thalamus terminates in the lateral nucleus of the amygdala and the lateral part of its central nucleus. The other system begins in the intralaminar and midline nuclei and in the mediodorsal nucleus of the thalamus. It reaches the remaining nuclei of the amygdala. Amygdalopetal connections of the interlaminar and middline nuclei of the thalamus, especially those arising in the paraventricular and parataenial nucleus, are mostly bilateral.

Amygdala↗
PubMed1978

The distribution of axon terminals with flattened vesicles in the nuclei of the amygdaloid body of the cat.

The morphology of synapses in the amygdaloid nuclei was studied in 10 cats. On the basis of the percentage of axon terminals with flattened vesicles (F-type) nuclei were distinguished, in which these terminals are as sparsely distributed as in most areas of the central nervous system, from other nuclei in which they are abundant (about one-third to one-half of all synaptic boutons). The lateral, basal dorsal and basal ventral nuclei belong to the first, the medial and central nucleus and the anterior amygdaloid area--to the second group. The cortical nucleus, which generally has a small number of boutons of F-type has some parts seemingly belonging to the first, and others to the second group. In all amygdaloid nuclei axon terminals of F-type form symmetrical synaptic contacts. In nuclei with a low percentage of F-type terminals these boutons are predominantly small and synapse either with perikarya or with large dendrites. The amygdaloid nuclei having numerous F-type terminals contain not only small but also larger terminals with flattened vesicles. Both, the larger and smaller axon terminals form in these nuclei synaptic contacts with various parts of dendrites even with very small ones and with dendritic spines. The subdivision of amygdala into two parts, one with a low and another with a high number of F-type boutons would seem to support the hypothesis that amygdala may be subdivided physiologically into a dorsomedial--"excitatory" and basolateral--"inhibitory" portion.

Amygdala↗