PubMed Health⌕ Search

Biomedical subjects

O Narkiewicz

Publications and source records attributed to O Narkiewicz.

At least 55 records · Page 3Linked to original sources
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↗
PubMed1976

Localization of acetylcholinesterase activity in the amygdaloid body of man.

The localization of acetylcholinesterase (AChE) activity in the nuclei of the amygdaloid body of man was studied by Gerebtzoff's modification of Koelle's acetylthiocholine method on 10 human brains. To compare the histochemical results with the cytoarchitectionics, additionally sections from 10 human brains were stained with cresyl violet. The intensity of AChE activity in the different amygdaloid nuclei varied widely. The high AChE activity occurred in the basal lateral nucleus and in the lateral part of the central nucleus. Very little activity was found in the medial nucleus and in the intermediate part of the central nucleus. All remaining nuclei showed AChE activity of moderate intensity. In almost each amygdaloid nucleus, differences of AChE activity among various areas were observed. In the amygdala of man all nuclei described in animals were found except nucleus of the lateral olfactory tract. Most of the human amygdaloid nuclei show more differentiated structure than in lower mammals in terms of not only cytoarchitectonic subdivision, but also in the intensity of AChE activity.

Acetylcholinesterase↗
PubMed1974

Types of synapses in the claustrum of the cat.

Basing on structure of synaptic vesicles, symmetry of presynaptic and postsynaptic densities, and size of synaptic boutons, various types of synapses were found in the claustrum. Most of the synapses connect axon terminals with dendritic spines or small dendrities. They are usually asymmetrical with evident postsynaptic thickening. To this type, synapses between corticofugal axons, and claustral cells belong. Synapses between the axon terminals and larger dendrites or cell pericarion are much less frequent, 1-10 synaptic boutons adhering to pericarion were found on a single section of the claustral cell. Axoaxonic and crest-synapses also were found.

Animals↗