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J Moryś

Publications and source records attributed to J Moryś.

At least 55 records · Page 3Linked to original sources
PubMed1999

The basolateral amygdaloid complex--its development, morphology and functions.

For many years the amygdaloid body has been an object of numerous investigations on different species, because the basolateral complex, being the main part of the amygdaloid body, is regarded as "sensory input" to this structure. It plays a very important role in so called emotional memory and learning, what is particularly important in early developmental stages. Impairment at this time may cause psychiatric problems in later life, like neurosis, phobia, unconscious fear or panic attacks. Complicated functions of the basolateral complex require precise control and modulation especially in early development. In this review the morphological changes during the development and maturation will be discussed and compared with neurotransmitter as well as with the expression of the calcium binding proteins at various stages of the development.

Amygdala↗
PubMed1998

The cortico-related zones of the rabbit claustrum-study of the claustrocortical connections based on the retrograde axonal transport of fluorescent tracers.

The claustrocortical connections in the rabbit were assessed for the first time by the method of axonal retrograde transport of two fluorescent tracers (Fast Blue and Diamidino Yellow). The material consisted of 23 adult New Zealand rabbits. Projection zones of spindle-like form, connected with the precentral, postcentral, temporal and occipital cortices have been delineated. They are organized topographically both in the anteroposterior and ventrodorsal direction. The precentral (motor) projection zone is localized in the anterodorsal part of the claustrum. It may be divided into two separate parts that project to the medial and lateral part of the precentral cortex. The large postcentral (somatosensory) zone occupies mainly the central part, whereas the temporal (auditory) and occipital (visual) zones are situated in the posteroventral part of the claustrum. The overlap of various claustral projection zones is differentiated, the largest being that of the somatosensory zones. In comparison to the results of study of claustral projection zones performed on other species, presumably on the rat and cat, its seems plausible to conclude that the extension of claustral projection zones and degree of their overlap in the rabbit represent an intermediate character.

Animals↗
PubMed1998

Visual zone of the claustrum shows localizational and organizational differences among rat, guinea pig, rabbit and cat.

The retrograde axonal transport method was used to compare the topography and organization of the visual zone of the claustrum in rat, guinea pig, rabbit and cat. First, massive Fluoro-Gold injections were placed into the primary visual cortex and the secondary areas. Experiments showed differences in the location of the visual zone among the animals under study. In rat, the visual zone occupied the posteroventral part of the claustrum and spread to its anterior pole. In guinea pig, neurons projecting to the visual cortex were located dorsally in the posterior half of the claustrum. In rabbit, similarly to the rat, they were localized in the posteroventral part; however, they did not reach the anterior pole. In cat, neurons that project to the visual cortex were concentrated dorsally in the posterior fourth of the claustrum. In double-injection experiments, Fast Blue and Diamidino Yellow were placed into the primary and secondary visual areas in various combinations. The experiments showed that in the rat and the rabbit claustral neurons project to primary visual cortex (area 17) as well as to both secondary visual areas (areas 18a and b). Populations of neurons sending axons to the primary and secondary areas showed full overlap. The presence of double-labeled neurons indicates that some claustral neurons project both to the primary and secondary fields. In cat, neurons that project to the primary visual cortex appear to be clearly separated from those connected with the secondary visual area, as no double-labeled neurons were found. In all studied species, the double injections placed into the visual and primary somatosensory cortex did not result in any double-labeling neurons. Our results indicate that the location of the visual zone in the posterior part of the claustrum is a phylogenetically stable feature, whereas its dorsoventral shift as well as the extent toward the anterior pole is related to the particular species. The overlap of neurons projecting to the primary and secondary visual areas in the rat and rabbit as well as the separation of both projections in cat appear to reflect the higher degree of complexity of the visual system in the latter.

Animals↗
PubMed1998

Postnatal development of the rat striatum--a study using in situ DNA end labeling technique.

We have examined the development of rat striatum for evidence of cells dying in the process of physiological cell death. In present study we have indicated apoptotic cells in sections stained with cresyl violet (cell death characterized by pyknosis) or with DNA end labeling assay (TUNEL method). Our results demonstrated that cell loss during maturation of the rat striatum had the characteristics of apoptosis rather than necrosis. The greatest number of TUNEL-positive and pyknotic cells in the striatum were found during the first postnatal days; after 7th day of postnatal life a rapid decrease of its number was observed after the second postnatal week no TUNEL-positive cells were observed in the striatum. Our analysis suggests that apoptotic cell death occurring during the development of striatal neuronal population takes place during the first week of postnatal life.

Aging↗
PubMed1998

Ultrastructural organization of the visual zone in the claustrum of the cat.

Data obtained by using ultrastructural and morphometric approaches revealed three types of neurons in the cat visual claustrum. The most numerous were medium-sized and large ones. They formed 3/4 of the cell population. The ultrastructural properties of those cell types were largely similar. Their cell bodies were oval, round, fusiform or triangular and contained more or less indented nuclear envelope. The cytoplasm of those cells was characterized by a high concentration of subcellular organelles and particularly rough endoplasmic reticulum. The characteristic feature of those cells was a low nucleus/cell body area ratio (47 +/- 1% and 43 +/- 1%, respectively). The proximal dendrites of medium-sized cells were usually wide at the base, relatively short and tapering, whereas, those arising in the large cells were often thick and had a short tapering base. The neurons described above stained by Golgi impregnation method showed spines on their distal dendrites both under the light and electron microscopy. The retrograde axonal transport of HRP and WGA-HRP following injections into the visual cortex confirm that they are mainly projection cells which form the ascending limb of the claustrocortical loop. The third type of neurons formed a less numerous group of small cells which differed from the larger ones in various respects. They possessed the large nuclei with deeply indented nuclear envelope and comparatively a thim layer of cytoplasm poor in subcellular organells among which free ribosomes and mitochondria were common. The nucleus/cells body area ratio high (59 +/- 2%). In Golgi preparations their dendrites did not show spines. The dendrites originating from that type of neurons were thin, long and did not posses a wide tapering base. They are mainly claustral intrinsic neurons.

Animals↗
PubMed1998

The projection of the amygdaloid nuclei to various areas of the limbic cortex in the rat.

The connections of the amygdaloid body with the areas of the limbic cortex in the rat were studied by means of the method on the axonal retrograde transport of the fluorescent tracer FluoroGold. The tracer was injected into the anterior and posterior limbic cortices (cingulate gyrus, granular and agranular retrosplenial area, respectively. The localization of the corresponding amygdalar projection zones was investigated and the semiquantitative analysis of the connections was conducted. The projection zones in the rat amygdaloid body are organized topographically. Administration of the fluorescent tracer to the anterior and posterior part of the limbic cortex in the rat (cingulate gyrus and both retrosplenial areas, respectively) reveals labeling of cells only for injections to the former one. The labeled cells were present only in the major components of the basolateral amygdaloid complex. The main source of this projection was anterior part of basolateral nucleus (BLA). Some labeled neurons were found in the lateral nucleus and few in the ventral part of basolateral nucleus. No labeled cells were found within the basomedial nucleus.

Amygdala↗
PubMed1998

Parvalbumin immunoreactivity changes in the thalamic reticular nucleus during the maturation of the rat's brain.

The thalamic reticular nucleus (Rt) is a thin lamina of cells, through which thalamocortical and corticothalamic fibers pass. It is interposed between the thalamic nuclei and the internal capsule and it is composed of GABA-ergic cells with synapses that receive impulses from both kinds of fibers. Rt takes part in the negative feed-back system of controlling the information transfer from the thalamus to the cerebral cortex and it is focused in the sleep-waking cycle. The pattern of parvalbumin reactivity during maturation of Rt becomes the main aim of our study. The study was performed on 36 rats on various postnatal days (P0, P1, P2, P4, P5, P7, P10, P14, P17, P21, P30 and P90). The animals were anesthetized, transcardially perfused, cut on cryostat into 30-microns-thick frontal sections, stained immunocytochemically using standard ABC method and a mouse monoclonal antibody against parvalbumin. A small amount of round and oval, parvalbumin immunopositive cells was detected at stage PO, predominantly in the intermediate part of Rt, whereas the cells in ventral and lateral part at the same time were only slightly immunopositive. At P10 the cells in the intermediate part became more fusiform or oval because of the appearance of dendrites. At P14 we were able to observe separate, punctuated structures interpreted as the axonal endings. There were plenty of them at the time of full maturation of the intermediate portion of reticular nucleus (stage P21). At this time, the dorsal and ventral parts had their first synapses, too, but their maturation ended a week later. At P30 multipolar neurons, with round and fusiform somata were distributed relatively homogeneously throughout Rt. We compared the stage with the parvalbumin reactivity of the adult rat and found no difference in the morphological pattern of PV neurons.

Animals↗
PubMed1998

The pattern of synaptophysin changes during the maturation of the amygdaloid body and hippocampal hilus in the rat.

Synaptophysin is an integral membrane protein associated with small, electron-lucent synaptic vesicles. Immunohistochemistry for this protein is a sensitive method to study subtle changes in synaptic density and distribution in various brain regions. In the present study, the synaptogenesis was examined in the rat basolateral amygdala in comparison with the hippocampal hilus, from the day of birth to adulthood. A total of 41 brains at various ages starting from P0 to P90 (P--postnatal day) were examined. After perfusional fixation the brains were frozen and cut in the coronal plane and stained either with cresyl violet or standard immunohistochemical methods using the anti-synaptophysin antibody. Synaptophysin positive granules appeared just after birth in both structures, but their number was very low (about 0.28 x 10(6) and 0.13 x 10(6) per mm3 in the amygdala and hippocampus, respectively). In the basolateral amygdala the number of synapses increased rapidly reaching the maximum at P14 (1.6 x 10(6) per mm3) followed by about 45% decrease in number up to P30 and later being stabile. In the hippocampus two increases of the synaptogenesis were observed. The first at P7 (about 1.7 x 10(6) of synapses per 1 mm3) which was followed by dramatic decrease up to 0.7 x 10(6) per mm3 at P14. The second increase appeared later (about P90) and reached 1.7 x 10(6) per mm3. After that time the density of synapses was stabile. It may be supposed that the first characteristic wave of synaptogenesis observed in the hippocampus and amygdaloid body is due to the overproduction of synapses observed at that time in other cortical regions. The late wave of synaptogenesis found in the hippocampus is related to the great plasticity of the interneuronal connections in this period of development.

Amygdala↗
PubMed1998

The corticoclaustral connections in the rat studied by means of the fluorescent retrograde axonal transport method.

The corticoclaustral connections in the rat were investigated by means of the method of the retrograde axonal transport of the fluorescent tracer (Fluoro-Gold; FG). The material consisted of 20 adult Wistar rats. The fluorescent tracer was injected into the anterior, middle or posterior parts of the claustrum. The retrogradely labeled neurons were detected in the layer VI of the neocortex. Injections of the tracer into the anterior part of the claustrum resulted in labeling of the neurons in the motor cortex. After administration of the tracer into the middle part of the insular claustrum, labeled neurons were present both in the motor and somatosensory cortices, while the injections of the tracer into its posterior part resulted in labeling of neurons in the visual cortex. Administration of the fluorescent tracer into the insular claustrum of the rat resulted in labeling of the cortical neurons of the corresponding areas of both hemispheres, however, the contralateral projections seem to be less numerous than the ipsilateral. Our results confirm the existence of reciprocal connections of the claustrum with the neocortex and suggest its role in integration and modification of information reaching the neocortex.

Animals↗
PubMed1998

The amygdaloid body of the rabbit--a morphometric study using image analyser.

The amygdaloid body is a telencephalic structure belonging to the limbic system. The amygdaloid body consists of the two main nuclear groups: corticomedial and basolateral. The former-phylogenetically older group is composed of the central, medial, and cortical nuclei, while the latter, phylogenetically younger one, of the lateral, basolateral and basomedial ones. The results presented in our paper indicate differences in the structure and topography of the specific amygdaloid nuclei. Their subdivisions in the rabbit are not as evident as in the rat. Apart from structural differences, the cellular composition of specific nuclei does not differ distinctly. It can suggest that their intrinsic and extrinsic connections might be similar and the role and function of them is maintained (with few exceptions) through the phylogeny.

Amygdala↗
PubMed1997

Rat's claustrum shows two main cortico-related zones.

Methods of retrograde axonal transport were employed to evaluate the topography and overlap of claustroneocortical connections in the rat. Fluorescent tracers Fast Blue (FB) and Diamidino Yellow (DY) were injected simultaneously in various combinations into the motor, somatosensory, auditory and visual cortical areas. Experiments showed that claustroneocortical projections are organized in two main cortico-related zones: sensorimotor and visuoauditory. The sensorimotor zone occupies the anterodorsal part whereas the visuoauditory occupies the posteroventral part of the claustrum. Between these two main zones only a scanty overlap was observed. In the sensorimotor zone a large overlap between neurons projecting to the motor and somatosensory cortical areas exists. The visuoauditory zone is characterized by a full overlap of neuronal populations projecting to the visual and auditory areas.

Amidines↗
PubMed1997

Neuronal changes in the basolateral complex during development of the amygdala of the rat.

Neuronal changes in the amygdala basolateral complex were studied during development and maturation in fetal and postnatal rat brains using morphometrical methods. Forty brains of animals of various ages were fixed in formalin, frozen and cut into 25 microm thick sections and stained with cresyl violet or haematoxylin and eosin (H&E). In cresyl violet preparations, the complex appeared for the first time on embryonic day (E)17 and was composed of two homogeneous nuclei lateral and basolateral. On about the seventh postnatal day, each of these nuclei was divided into two parts the first one into the dorsolateral and ventromedial and the second one into the anterior and posterior. Morphometric investigations showed a different increase of the neuronal and nuclear size in various parts of the basolateral complex up to postnatal day (P)14; after that time these parameters did not change significantly. The neuronal density and the total number of neurons stabilized at P7 in all parts of this complex, except for the dorsolateral part of the lateral nucleus in which a 30% decrease of the total number of cells was observed. From P14, in all nuclei under study, the total number of neurons did not change significantly.

Amygdala↗
PubMed1997

Volume and topographical changes of the basolateral complex during the development of the rat's amygdaloid body.

Volume and topography of basolateral complex during development and maturation in fetal and postnatal rat brains were studied using morphometrical methods. 39 rat brains of various ages were fixed in formalin, frozen and cut into 25-micron-thick sections and stained with cresyl violet. In cresyl violet preparation the basolateral complex appeared first on 17th prenatal day and it was composed of two homogenous parts--lateral and basolateral nuclei. On about 7th postnatal day each of these nuclei divided into two parts--the first one into the dorsolateral and ventromedial part, while the second one--into the anterior and posterior parts. Morphometric investigations showed that volume of the basolateral complex and its parts underwent the biggest changes up to 14th postnatal day, and we suspected that during this time it was more sensitive to pathological changes. After that day the volume of the basolateral complex had changed only a little.

Amygdala↗
PubMed1997

Some claustral neurons projecting to various neocortical areas show morphological differences.

The morphology of claustral neurons projecting to the motor, somatosensory, auditory and visual cortical areas in the rat was analyzed by means of combination of axonal retrograde transport and morphometric analysis. Fluoro-Gold (FG) injections placed into various cortical fields resulted in labeling in the claustrum four neuronal types: pyramidal with thick main dendrite, oval with a few thin dendrites spreading out in various directions, fusiform possessing two main dendrites arising from opposite poles of the cell body and polygonal. Pyramidal neurons prevailed in populations of neurons projecting to the motor cortex of the contralateral hemisphere. Oval neurons outnumbered other types in populations projecting to the somatosensory, auditory and visual cortical fields. The number of fusiform and polygonal neurons did not exceed at 12.5% together in any populations. Neurons projecting to the contralateral hemisphere were the largest claustral neurons (mean cross-section are 167.19 +/- 2.9 micron 2) whereas neurons projecting to the motor cortex where the largest claustral neurons projecting ipsilaterally (141.89 +/- 2.22 micron 2). There was no significant difference between neurons projecting to the somatosensory (113.46 +/- 1.9 micron 2) cortex and to the visual (111.8 +/- 1.4 micron 2) cortex whereas neurons related to the auditory are (95.98 +/- 1.75 micron 2) were the smallest claustral neurons. These observations pointed out that the morphology of claustral neurons is closely related to a cortical area to which they send axons.

Animals↗
PubMed1996

Subpopulation of dogs with severe brain parenchymal beta amyloidosis distinguished with cluster analysis.

A study of the brains of 30 dogs, mongrels from 6.5 to 26.5 years of age, revealed that all dogs older than 13 years of age develop amyloid-beta-positive plaques. Cluster analysis based on the age of the dogs and the numerical density of amyloid-positive plaques stained with monoclonal antibody 4G8 (17-24aa) revealed that the population of old dogs consists of two subpopulations: one with a very low (0.8/mm2 on average) and other with a high (19.2/mm2 on average) numerical density of plaques. These two groups (19.5 and 19.1 years of age, respectively) appear to emerge from the younger group (12.2 years of age on average), with moderate (2.2/mm2 on average) numerical density of 4G8-positive plaques. These data may indicate that only a portion of the mongrel population (43%) is susceptible to amyloidosis beta or that only this severely affected subpopulation was exposed to a factor or factors inducing this pathology and developed severe cortical amyloidosis that correlates with age. Dog plaques are only of the diffuse type, with nonfibrillar, thioflavin S-, and Congo red-negative amyloid in all groups distinguished by cluster analysis. Only from 10% of 4G8-positive plaques in the mildly affected group to 29% in the severely and 37% in the moderately affected group are Bielschowsky positive. In the younger, moderately affected group, 6E10 (1-17aa)-positive plaques prevail. In the two old groups with severe and weak changes, almost all 4G8-positive plaques are also 6E10-positive. Carboxy-terminal region immunocytochemistry reveals that BC42-positive plaques are numerous, whereas BC40-positive plaques are few or absent. The differences in the silver-positivity of plaques and their immunoreactivity in both the amino- and carboxy-terminal regions may reflect differences in amyloid-beta deposition and resolution. Dog parenchymal amyloidosis beta appears to be a model for the study of diffuse plaques.

Amyloid beta-Peptides↗
PubMed1996

Loss of neurons in the claustrum of aging brain.

The study was performed on 19 brains of nondemented patients with age ranging from 36 to 89 years. After embedding in paraffin, coronal 8-microns-thick serial sections were cut and stained either with cresyl violet or with immunocytochemical methods for amyloid and tangles. Morphometrical studies were performed in all parts of the claustrum along its whole extension. Changes related to aging (neuronal loss and decrease in volume) were found in all parts of the claustrum, but the time of origin of these changes is different in various parts of this structure. We did not observe neurofibrillary pathology in any parts of the claustrum. In the oldest subjects a small number of amyloid plaques was found in the paraamygdalar part of the claustrum. We suggest that the neurons of the claustroneocortical loop are affected severely and earlier than those in the claustroentorhinal loop.

Adult↗
PubMed1996

Division of the human claustrum according to its architectonics and morphometric parameters.

The topography and cytoarchitectonics of the claustrum as well as morphometric parameters of its neurons were studied in 10 human brains obtained from patients without any detectable neuropathological changes. We distinguished four parts of the claustrum: dorsal, orbital, temporal and paraamygdalar. The dorsal and orbital parts contain larger cells, than those of the temporal and paraamygdalar parts, although these differences were statistically non significant. The highest neuronal density was observed in the paraamygdalar part. The nucleus and nucleus@cell body area ratio was significantly smaller in the dorsal part than in other parts of the claustrum. We described three types of neurons in the claustrum: (1) medium-sized either fusiform or triangular cells with darkly stained cytoplasm; they predominate in the dorsal and temporal parts, (2) medium-sized as well as large cells, either multipolar or pyramidal-like with lightly stained cytoplasm; they are most numerous in the orbital and paraamygdalar parts, (3) small, multipolar or oval neurons with darkly stained ring of cytoplasm; these types of neurons are uniformly distributed throughout all parts of the claustrum. The subdivision of the human claustrum is in accordance with our observations that each of these parts possesses connections with different cortical regions.

Basal Ganglia↗