bluuebunny/crossref_metadata_2025_split huggingface dataset:
Histochemical demonstration of zinc in the hippocampal region of the domestic pig: I. Entorhinal area, parasubiculum, and presubiculum
Authors: Holm Ida E. , Geneser Finn A. 
Published: January 2005

AbstractA detailed description is given of the distribution of zinc in three areas of the domestic pig hippocampal region, viz., the entorhinal area, the parasubiculum, and the presubiculum. Zinc was demonstrated histochemically with use of the Neo‐Timm method, a recent modification of the sulphide silver procedure. Each of the studied areas showed a distinctly stratified staining pattern, which has been correlated in detail to fields and layers defined on the basis of cyto‐ and fibroarchitecture, providing a combined chemo‐ and cytoarchitectonic map. The staining was primarily confined to the neuropil, although stained nerve cell bodies were encountered in all three parts of the hippocampal region.Two main subfields were identified in the entorhinal area that have been designated pars medialis and pars lateralis, in accordance with their topographical positions, but both the cytoarchitecture and Neo‐Timm staining pattern are indicative of further subdivision. In pars medialis, the deep half of layer I, the interstices between the stellate cell bodies in layer II, and layer III were medium to heavily stained, whereas layer IV stained weakly. Layers V‐VI were slightly darker than layer IV and were inseparable on the basis of the Neo‐Timm staining. The staining of pars lateralis differed in many respects from that of pars medialis, the most conspicuous feature being a much lighter layer III. In the parasubiculum, the deep half of layer I together with layers II‐III had the appearance of an intensely stained triangle wedged in between the entorhinal area and the presubiculum. The latter showed moderate staining of the inner half of layer I and posterior part of layer II, while layer IV was stained intensely. Layers III and V‐VI exhibited only weak staining.The distribution of zinc in the pig was compared with that in the guinea pig and rat, described previously. Although many histochemical features are shared by the staining patterns of the three species, striking differences exist in the pig, the most notable being the virtually reverse staining of the entorhinal layer IV.The possible functional implications of zinc in synaptic vesicles are considered.
Quantitation of catecholamine neurons in the locus coeruleus in human brains of normal young and older adults and in depression
Authors: Chan‐Palay V. , Asan E. 
Published: January 2005

AbstractA quantitative study of the morphology and distribution of norepinephrinergic neurons in the human locus coeruleus (LC) is given for normal young and older adult brain. Norepinephrine (NE)‐producing neurons are identified by immunocytochemistry of two NE biosynethetic enzymes, tyrosine hydroxylase (TH) and dopamine‐β‐hydroxylase (DBH), visualized by the peroxidase‐antiperoxidase and immunogold‐silver‐staining methods. TH and DBH immunoreactions yield equivalent results. Both immunocytochemical visualization methods allow detailed analysis of neuronal morphology. The neurons of the human LC fall into four classes: large multipolar neurons with round or multiangular somata, large elliptical “bipolar” neurons, small multipolar neurons, and small ovoid “bipolar” neurons. Though most of the neurons contain neuromelanin pigment, some larger neurons lack pigmentation. Dendritic arborization of all neurons is extensive. Computer‐assisted quantitative measurements of the parameters somatic size, dendritic arbor length, surface area, and volume are given. Somatic areas of LC neurons of all four classes are decreased in older adult brain, but dendritic arborization is equally extensive as in the younger. The rostrocaudal length of the LC is approximately 15 mm, and no age‐dependent decrease is observed. Computer‐assisted mapping of immunoreactive neurons and three‐dimensional reconstruction allow division of the LC into rostral, middle, and caudal parts with characteristic distribution of neurons. Small neurons predominate in all parts, but the relative contribution of larger cells decreases in a rostrocaudal direction. A cell loss of 27–37% occurs in older adult brains and to 55% in the brain of a chronically depressed patient without dementia. Cell loss is highest in the rostral part, lower in the middle and absent in the caudal part, and more small cells are lost than larger ones.
Spectra of G ratio, myelin sheath thickness, and axon and fiber diameter in the guinea pig optic nerve
Authors: Guy John , Ellis E. Ann , Kelley Kay , Hope G. Marion 
Published: January 2005

AbstractThe spectra of fiber and axon diameter, myelin sheath thickness, fiber density, and g ratio of the optic nerve were analyzed for the strain‐13 guinea pig, an animal extensively utilized in the investigation of experimental disorders of demyelination. Our detailed analytical study of the normal guinea pig optic nerve provides the basis for comparison to disease states and the morphology of other species. As in the rat, mouse, and chipmunk, fiber diameters in the guinea pig were unimodal, but dissimilar to the trimodal fiber spectra of the cat and primate. The predominance of medium‐sized fibers (0.80–2.00 μm), common to most species, contributed to the larger mean fiber diameter (1.45 μm) of the guinea pig optic nerve, in which small fibers (0.50 μm or less) were infrequent and fibers larger than 5.00 μm in diameter, seen in the cat and primate, were absent. While myelin sheath thickness increased with axon diameter in the guinea pig, as in other species, a g ratio of 0.81 in the guinea pig was greater than in most mammals. Since conduction velocity is dependent on axon size, as well as myelin properties, the relatively larger mean axon diameter of the guinea pig optic nerve (1.18 μm) may compensate for the decrease in its myelination.
Immunohistochemical localization of GAP‐43 in the developing hamster retinofugal pathway
Authors: Moya Kenneth L. , Jhaveri Sonal , Schneider Gerald E. , Benowitz Larry I. 
Published: January 2005

AbstractMetabolic labeling studies have shown that the developing hamster retinotectal pathway is marked by a high level of synthesis and axonal transport of the neuron‐specific phosphoprotein GAP‐43, which then decline sharply with synaptic maturation. To understand better the relationship of GAP‐43 to specific developmental events, we used a monospecific antibody to examine the location of this protein in the optic tract and retinal target areas at various stages. In late embryonic and in neonatal hamsters, dense GAP‐43 immunostaining was seen along the entire extent of the optic tract axons, including fascicles coursing over and through the lateral geniculate body (LGB) and within the upper layers of the superior colliculus (SC). The retinal origin of many of these fascicles was confirmed by their rapid disappearance after removal of the contralateral eye. During the first postnatal week, immunostaining in the fiber fascicles showed a marked decline, though the protein was still present throughout the neuropil of the LGB and SC. In the second postnatal week, the neuropil staining also diminished, and by 12 days after birth, both structures showed only light immunoreactivity. The high levels of GAP‐43 in embryonic and neonatal optic tract axons coincide temporally with axon elongation, initial target contact, and collateral formation by the retinofugal fibers, whereas subsequent concentration of the protein in the neuropil suggests its involvement in the elaboration of terminal arbors and synaptogenesis.
Immunoelectron‐microscopic localization of the 180 kD component of the neural cell adhesion molecule N‐CAM in postsynaptic membranes
Authors: Persohn Elke , Pollerberg G. Elisabeth , Schachner Melitta 
Published: January 2005

AbstractIn order to investigate the expression of cell adhesion molecules in synapses, we have studied the localization of the neural cell adhesion molecule N‐CAM in the cerebellum and hippocampus of adult mice by immunocytological and immunochemical methods. Of the three molecular components of N‐CAM with relative molecular masses (Mr) of 120, 140, and 180 kD, N‐CAM 120 is not detectable in synaptosomal membranes, whereas N‐CAM 140 is expressed on both pre‐ and postsynaptic membranes and N‐CAM 180 is restricted to postsynaptic sites, with localization of the N‐CAM 180‐specific epitope in postsynaptic densities. Specificity of immunoreactivity is indicated by the observation that antibodies to the neural cell adhesion molecule L1 do not label synaptic membranes, whereas antibodies to two major components of postsynaptic densities, actin and erythrocyte spectrin, react with synaptic structures. Interestingly, N‐CAM 180 is only detectable in subpopulations of synapses in the intact tissue. Isolated synaptosomes, opened for unimpeded accessibility of antibody by hypoosmotic treatment, also reveal a partial expression of N‐CAM 180 in that 67% are labeled by antibodies to N‐CAM 180, while antibodies to actin and erythrocyte spectrin react with 95% and 88% of all synaptosomes, respectively. N‐CAM 180 does not appear to be differentially expressed in synapses of a particular morphological type, but is detectable in all types of synapses in the cerebellum and hippocampus, except for mossy fiber synapses and synapses between basket and Purkinje cells, which are generally N‐CAM 180‐negative. Since N‐CAM 180 has been shown to be characteristic of stabilized or stabilizing cell contacts, possibly by its association with the cytoskeleton‐membrane linker protein spectrin (Pollerberg et al.: J. Cell Biol. 101: 1921–1929, '85; Nature 324: 462–465, '86; Cell Tissue Res. 250: 227–236, '87), we would like to suggest N‐CAM 180 plays an important role in determining the stability of contacts between pre‐ and postsynaptic membranes and state of synaptic activity.
Cholinergic and monoaminergic innervation of the cat's thalamus: Comparison of the lateral geniculate nucleus with other principal sensory nuclei
Authors: Fitzpatrick David , Diamond Irving T. , Raczkowski Denis 
Published: January 2005

AbstractThe cholinergic and monoaminergic innervation of the lateral geniculate nucleus (GL) and other thalamic nuclei in the cat was examined by using immunocytochemical and tract‐tracing techniques. Cholinergic fibers, identified with an antibody to choline acetyltransferase (ChAT), are present in all layers of the GL. They are fine in caliber and exhibit numerous swellings along their lengths. The A layers, the magnocellular C layer, and the medial interlaminar nucleus are rich in cholinergic fibers that give rise to prominent clusters of boutons, while the parvicellular C layers contain fewer fibers that are more uniformly distributed. The interlaminar zones are largely devoid of ChAT‐immunoreactive fibers. Double‐label experiments show that cholinergic projections to the GL originate from two sources, the pedunculopontine reticular formation (PPT) and the parabigeminal nucleus (Pbg). The PPT contributes cholinergic fibers to all layers, while Pbg projections are limited to the parvicellular C layers.The lateral geniculate nucleus has a much greater density of cholinergic fibers than the other principal sensory nuclei: the density of fibers in the A layers is more than three times greater than that in the ventral posterior nucleus (VP) or the ventral division of the medial geniculate nucleus (GMv). In contrast, serotonin (5‐HT)‐immunoreactive fibers are distributed with equal density across the principal thalamic nuclei, while tyrosine hydroxylase (TH)‐immunoreactive fibers (presumed to contain norepinephrine) are noticeably less dense in the GL than in the others. Monoaminergic fibers also differ from cholinergic fibers in their laminar distribution within the GL: both TH‐ and 5HT‐immunoreactive fibers are distributed evenly across the layers and interlaminar zones and are slightly more abundant in the parvicellular C layers than in the other layers.Other thalamic nuclei rich in cholinergic fibers include the pulvinar nucleus, the ventral lateral geniculate nucleus, the intermediate nucleus of the lateral group, the lateral medial and suprageniculate nuclei (Graybiel and Berson: Neuroscience 5: 1175–1238, '80), and the paracentral and central‐lateral components of the intralaminar nuclei. This pattern matches the distribution of projections from the PPT and is similar, but not identical, to the pattern of acetylcholinesterase staining. The fact that most of the nuclei rich in cholinergic fibers have been implicated in visual sensory or visual motor functions suggests that cholinergic projections from the reticular formation play an especially important role in visually guided behavior.
Development of glial cells in the cerebral wall of ferrets: Direct tracing of their transformation from radial glia into astrocytes
Authors: Voigt Thomas 
Published: January 2005

AbstractCoronal sections of the cerebral wall from developing ferrets (newborn to adult) were double‐stained with antibodies to vimentin and glial fibrillary acidic protein (GFAP). At birth, the dominant glial population was radial glia and these cells labeled only for vimentin. A small population of immature astrocytes in the cortical plate was double labeled for GFAP and vimentin. In successive days, the number of vimentin‐positive radial glia gradually decreased and they disappeared entirely at about 21 days. During this same period, the double‐stained astrocytes increased in number and were distributed throughout the cortical plate and intermediate zone. After 6 weeks of age the astrocytes were mostly confined to the developing white matter. Around this time they gradually lost their vimentin staining, and in the adult no vimentin‐positive elements were seen except at the ependymal surface.In newborn ferrets single radial glial cells were also visualized by applying the carbocyanine dye DiI onto the pial surface of fixed brains. While most radial glia extended from the ventricular zone to the pial surface, a substantial fraction of them had lost their contact to the ventricular zone. Their somata were displaced into the subventricular zone and lower portion of the intermdiate zone.The possibility that radial glia transform into astrocytes was directly tested by injecting fluorescent dyes under the pial surface of newborn ferrets at a time when virtually no GFAP‐positive astrocytes are present. The tracer, which was taken up in the upper portion of the cortical plate, stained the radial glial cell somata in the ventricular zone in a similar way as the dye DiI did in the fixed brains. As the radial glial cells disappeared at successively longer survival times, the tracer was ultimately found within newly formed GFAP‐positive astrocytes. These results provide strong support for the hypothesis that radial glia cells are the immature form of astrocytes (Choi and Lapham: Brain Res. 148:295–311, ′78; Schmechel and Rakic: Anat. Embryol. (Berl.) 156:115–152, ′79), and also show that, at least in the ferret cortex, the transformation is accompanied by a change in the expression of intermediate filament protein.
Correlated light and electron microscopic study of dopaminergic neurons and their synaptic junctions with DARPP‐32‐containing cells in three‐dimensional reaggregate tissue culture
Authors: Won L. , Price S. , Wainer B. H. , Hoffmann P. C. , Bolam J. P. , Greengard P. , Heller A. 
Published: January 2005

AbstractAn antibody to tyrosine hydroxylase has been used in a correlated light and electron microscopic study to characterize dopaminergic neurons and synaptic junctions in three‐dimensional reaggregate cell culture. Dissociated fetal mesencephalic cells containing dopamine neurons were coaggregated with dissociated fetal striatal cells in rotatory culture for 21 days. Sections of the coaggregates were stained by the peroxidase anti‐peroxidase technique to reveal tyrosine hydroxylase‐immunoreactive structures. Clusters of immunoreactive perikarya as well as dendrites and axons were observed. Immunolabeled perikarya were round or oval and approximately 20 μm in diameter. Boutons immunoreactive for tyrosine hydroxylase formed symmetric synapses, primarily with unlabeled dendritic shafts. Symmetric membrane specializations were also observed between tyrosine hydroxylase‐positive boutons and unlabeled dendritic spines as well as with the perikaryon of an unlabeled medium‐size neuron possessing a slightly indented nucleus.To characterize the neurochemical nature of the neurons postsynaptic to tyrosine hydroxylase‐positive boutons in the reaggregates, an antibody against DARPP‐32 (a dopamine and adenosine 3′:5′‐monophosphate‐regulated phosphoprotein) and an antibody against tyrosine hydroxylase were employed to visualize striatal dopaminoceptive neurons and dopaminergic structures, respectively, in the same section. Examination of reaggregate sections at the light microscopic level demonstrated that DARPP‐32‐immunoreactive cells were distributed into discrete clusters that were associated with patches of tyrosine hydroxylase‐positive axonal varicosities. Ultrastructural analysis of tyrosine hydroxylase‐positive boutons in such clusters revealed that dopaminergic axons synaptically contacted DARPP‐32‐immunoreactive neurons as well as unlabeled neuronal structures.The results demonstrate that dopaminergic neurons in reaggregate cells in culture do form synaptic contacts and the DARPP‐32‐containing neurons are a subset of striatal cells that receive a dopaminergic innervation.
Compartmental organization of the ventral striatum of the rat: Immunohistochemical distribution of enkephalin, substance P, dopamine, and calcium‐binding protein
Authors: Voorn Pieter , Gerfen Charles R. , Groenewegen Henk J. 
Published: January 2005

AbstractIn the caudate‐putamen of the rat a patch/matrix organization can be recognized on the basis of the immunohistochemical distribution of several markers, which include enkephalin, substance P, dopamine, and calcium‐binding protein. In the present experiments the distributional relations of these markers were investigated in the nucleus accumbens. The distribution of enkephalin fibers shows different inhomogeneities according to their location in the nucleus. Rostrally, heavily labeled areas stand out against a moderately stained background, whereas caudally, in medial and ventral parts of the nucleus, lightly stained areas delineate regions in the moderately stained neuropil. In the distribution of substance P, areas with high staining intensity were observed in the medial and ventral parts of the nucleus accumbens. Inhomogeneities in the distribution of strong dopamine immunoreactivity consist of weakly immunoreactive areas throughout the rostrocaudal extent of the nucleus accumbens and extremely heavily labeled areas in the medial and ventral parts of the nucleus. Calcium‐binding protein immunoreactivity can only be detected in dorsal parts of the nucleus. The generally intense immunostaining for calcium‐binding protein is interspersed with “blanks” of weak immunoreactivity.The heavily and moderately labeled enkephalin areas each maintain specific relations with inhomogeneities in the distribution of substance P, dopamine, and calcium‐binding protein. Rostrally, the heavily labeled enkephalin areas coincide with areas strongly immunostained for calcium‐binding protein and with lightly stained areas in the dopamine and substance P immunoreactivity patterns. In the same region lightly stained areas in the enkephalin distribution match heavily labeled substance P areas. Caudally, in the border region of the nucleus accumbens and the caudate‐putamen, the heavily labeled enkephalin areas are either related to “blanks” or to the intense staining regions in the calcium‐binding protein immunoreactivity distribution. The moderately labeled enkephalin areas caudomedially in the nucleus accumbens are in register with the heavily labeled regions in the distribution of substance P and with the extremely heavily labeled regions in the distribution of dopamine.Relations with connectivity are discussed and the inhomogeneities are compared to those in the caudate‐putamen. It is concluded that in the ventral striatum either one patch and one matrix compartment exist with different immunohistochemical relationships or there are several compartments with different immunohistochemical characteristics and different input‐output relations.
Morphology of retinal ganglion cells in lungless salamanders (Fam. Plethodontidae): An HRP and Golgi study
Authors: Linke Rüdiger , Roth Gerhard 
Published: January 2005

AbstractThe family Plethodontidae consists of nearly two‐thirds of all living urodeles; most of them possess highly developed visual abilities. We investigated the morphology of retinal ganglion cells (RGCs) in four representative species by means of the horseradish peroxidase method in flatmounts and in transverse sections and with the Golgi method in transverse sections. In flatmount preparations, four classes of RGCs were found, differing in dendritic arborization, dendritic field size, and stratification pattern of dendrites in the inner plexiform layer (IPL). Class‐1 cells had small dendritic fields (29–44 μm2) and arborized throughout the entire depth of the IPL. Class‐2 cells had medium to large dendritic fields (75–206 μm2) and mostly arborized in two or three laminae or in a diffuse fashion in the IPL. Class‐3 cells had medium to large dendritic fields (72–200 μm2) but sparse dendritic arborization. They only arborized in the proximal lamina of the IPL. Class‐4 cells had large dendritic fields (273–626 μm2) and branched in the most sclerad stratum of the IPL. No large differences in intraspecific soma size of the different RGC classes were detected (although interspecific soma size varied to a considerable degree) and no “giant” cells typically found in other vertebrate retinas were present.The results suggest that, with respect to the pattern of arborization and stratification of dendrites, lungless salamanders possess morphological classes of RGC similar to those found in frogs, but the morphology of RGCs in lungless salamanders seems to be simplified in comparison to frog RGCs. This simplification might be a consequence of paedomorphosis.
Carbohydrate components recognized by the cone‐specific monoclonal antibody CSA‐1 and by peanut agglutinin are associated with red and green‐sensitive cone photoreceptors
Authors: Röhlich Pál , Szél Ágoston , Johnson Lincoln V. , Hageman Gregory S. 
Published: January 2005

AbstractPrevious investigations have demonstrated that the monoclonal antibody CSA‐1 and peanut agglutinin label specifically cone photoreceptor cells. In the present study, we compared the binding of CSA‐1 and peanut agglutinin to that of the monoclonal antibodies COS‐1 and OS‐2, which have been shown to recognize the red/green‐ and blue‐sensitive cone visual pigments, respectively. Using lectin and immunocytochemistry on serial semithin sections of the pig retina, we have demonstrated in the present study that both CSA‐1 and peanut agglutinin label specifically the red‐, and green‐sensitive, but not the blue‐sensitive cone cell outer segments. Peanut agglutinin does bind, however, to the cone matrix sheaths associated with all three types of cones. These observations support the idea that red‐, and green‐sensitive cone cells share some common molecular epitopes and may represent a differentiation line of cones, considerably different from that of blue‐sensitive cones.