bluuebunny/crossref_metadata_2025_split huggingface dataset:
Amygdalonigral pathway: An anterograde study in the rat with Phaseolus vulgaris leucoagglutinin (PHA‐L)
Authors: Conzales Cathleen , Chesselet Marie‐Francoise 
Published: January 2005

AbstractThe projection from the central nucleus of the amygdala to the substantia nigra was labeled by injections of the anterograde tracer Phaseolus vulgaris leucoagglutinin into different subregions of the nucleus. A sparse projection of labeled bouton‐like swellings was observed in the rostral, medial substantia nigra pars compacta and ventral tegmental area from all subregions of the central nucleus of the amygdala that were injected. A dense projection of labeled axons and bouton‐like swellings was observed in the lateral part of the substantia nigra pars compacta and pars lateralis when the injection site included the dorsal and rostral central nucleus. Heavy labeling was also seen in the lateral retrorubral field in these cases. In no instances were labeled terminals observed in the substantia nigra pars reticulata. The same pattern of labeling in the lateral substantia nigra and retrorubral field was seen after injections rostral to the central nucleus or dorsal and medial to it in the sublenticular region. The results suggest that the amygdalonigral pathway contributes to the innervation of extensive areas of the substantia nigra pars compacta. The major component of the pathway, however, projects only to a subregion of the substantia nigra. The origin of this pathway is confined to a discrete region of the dorsal central nucleus of the amygdala but extends rostrally into an area that is part of the “extended amygdala.”
Cytochrome oxidase response to cochlea removal in chicken auditory brainstem neurons
Authors: Hyde Gregory E. , Durham Dianne 
Published: January 2005

AbstractChanges in cytochrome oxidase (CO) activity were studied in the chick brainstem auditory nuclei, n. magnocellularis (NM) and n. laminaris (NL), following unilateral cochlea removal. Chickens aged 10 days or 56 weeks underwent unilateral cochlea removal. Following survival periods of 30 minutes to 14 days for the 10‐day‐old birds and 6 hours or 14 days for the 56‐week‐old birds, the animals were perfused with paraformaldehyde/glutaraldehyde fixative. Cryostat sections of the brainstem were then prepared for CO histochemistry. Microdensitometry was used to quantify the difference in CO staining in NM and NL ipsilateral and contralateral to the cochlea removal. Since the cochlea projects to the ipsilateral NM, the contralateral NM was used as a within‐animal control.In normal chickens, NM cell bodies and the cell bodies and dendrites of NL neurons stain darkly for CO in both young and adult birds. In 10‐day‐old birds, there is no significant change in CO staining in NM from 30 minutes to 3 hours after cochlea removal. Then, a rapid biphasic change in CO staining was found in the ipsilateral NM. An increase in staining was observed 6 to 24 hours postoperatively, followed by a decrease in CO staining at 3‐ to 14‐day survival times. In the 56‐week‐old birds, no increases in CO staining were observed 6 hours after cochlea removal, but a decrease in CO staining was found 14 days postoperatively. In NL, no changes were observed until 3 days (10‐day‐old birds) or 14 days (56‐week‐old birds) after cochlea removal. Then a decrease in CO staining was observed in the dendritic and glial/fiber regions of NL containing axons from the deafferented NM.Thus it appears that afferent input has a regulatory effect on the oxidative metabolism of neurons in the chicken auditory brainstem nuclei, an effect that differs with the age of the animal at the time of afferent manipulation.
Structural homology of identified motoneurones in larval and adult stages of hemi‐ and holometabolous insects
Authors: Breidbach Olaf , Kutsch Wolfram 
Published: January 2005

AbstractThe set of neurones innervating the dorsal longitudinal muscles was studied with cobalt and nickel backfills in: (1) larval and adult locusts (Schistocerca gregaria and Locusta migratoria), (2) the larval and adult beetle (Zophobas morio), and (3) various segments of these insect species. In all specimens 11 neurones were encountered, which can be subdivided into a group of 7 motoneurones that stem from the next anterior ganglion and 4 neurones located in the ganglion of the segment containing the muscles. The latter group comprises 2 contralateral and 2 medial somata, of which one is a dorsal unpaired median neurone. The results were analysed under different aspects. This neural set and the basic structure of the dendritic fields is similar in: (1) different segments (serial homology), (2) the larval stage and imago of the same species with or without a pronounced metamorphosis (ontogeny), and (3) the studied hemi‐ and holometabolous insects (phylogeny). Our results support the notion that the structure of these neurones is conserved irrespectively of changes in the periphery and strategy of postembryonic development.
Distribution of 125I‐neurotensin binding sites in human forebrain: Comparison with the localization of acetylcholinesterase
Authors: Szigethy E. , Quirion R. , Beaudet A. 
Published: January 2005

AbstractThe distribution of 125I‐neurotensin binding sites was compared with that of acetylcholinesterase reactivity in the human basal forebrain by using combined light microscopic radioautography/histochemistry. High 125I‐neurotensin binding densities were observed in the bed nucleus of the stria terminalis, islands of Calleja, claustrum, olfactory tubercle, and central nucleus of the amygdala; lower levels were seen in the caudate, putamen, medial septum, diagonal band nucleus, and nucleus basalis of Meynert. Adjacent sections processed for cholinesterase histochemistry demonstrated a regional overlap between the distribution of labeled neurotensin binding sites and that of intense acetylcholinesterase staining in all of the above regions, except in the bed nucleus of the stria terminalis, claustrum, and central amygdaloid nucleus, where dense 125I‐neurotensin labeling was detected over areas containing only weak to moderate cholinesterase staining. At higher magnification; 125I‐neurotensin‐labeled binding sites in the islands of Calleja, supraoptic nucleus of the hypothalamus, medial septum, diagonal band nucleus, and nucleus basalis of Meynert were selectively associated with neuronal perikarya found to be cholinesterase‐positive in adjacent sections. Moderate 125I‐neurotensin binding was also apparent over the cholinesterase‐reactive neuropil of these latter three regions. These data suggest that neurotensin (NT) may directly influence the activity of magnocellular cholinergic neurons in the human basal forebrain, and may be involved in the physiopathology of dementing disorders such as Alzheimer's disease, in which these neurons have been shown to be affected.
Development of neuropeptide Y (NPY) immunoreactive neurons in the rat occipital cortex: A combined immunohistochemical‐autoradiographic study
Authors: Cavanagh Marion E. , Parnavelas John G. 
Published: January 2005

AbstractThe postnatal development of neuropeptide Y (NPY)‐immunoreactive neurons, previously labeled with [3H]thymidine on embryonic days E14–E21, has been studied in the rat occipital cortex. Immunohistochemistry combined with autoradiography showed evidence of a modified “inside‐‐out” pattern of maturation. NPY‐neurons are generated between E14 and E20 and are found in layers II–VI of the cortex and the subcortical white matter. NPY neurons from all these birthdates are overproduced at first, although cells generated at E16 produce the greatest excess, followed by E15 and E17. Some of these transient neurons are found in the “wrong” layer for their birthdates, and their elimination produces a more “correct” alignment at maturity. However, most of the NPY neurons that survive are generated at E17, and these cells are found throughout layers II–VI with a preponderance in layer VI. This evidence is strongly suggestive of cell death rather than merely cessation of production of NPY.
Plasticity of dorsal root and descending serotoninergic projections after partial deafferentation of the adult rat spinal cord
Authors: Polistina Dean C. , Murray Marion , Goldberger Michael E. 
Published: January 2005

AbstractPlasticity of dorsal root (DR) and descending serotoninergic (5‐HT) projections following dorsal rhizotomy fromL2 to S1 sparing L5 was studied by means of an intra‐animal comparison in the adult rat spinal cord. Projections of the chronically and acutely spared root were compared by cholera‐toxin conjugated horseradish peroxidase (CT‐HRP) injected into the sciatic nerves as the transganglionic tracer. Projections in unoperated controls, operated controls (acute bilateral spared root), and in experimental animals (chronic spared root on one side and acute spared root on the other) were mapped and the density was measured with an image analysis system. Labeled DRG cells and motor neurons were counted to determine if there were differences in the delivery of the label between the two sides. Measurements of the area of the dorsal horn and, separately, of the superficial laminae were made to control for shrinkage.DR projections were symmetrical in operated and unoperated controls, but a significant increase in DR projection density was found from L6 to L3 in the dorsal horn and Clarke's nucleus at L1 on the chronic spared root side in animals in which an equal number of DRG cells was labeled on the two sides. Density of 5‐HT immunoreactivity was symmetrical in controls. Ipsilateral to chronic spared root rhizotomy, the area fraction occupied by 5‐HT projections increased in Clarke's nucleus and in the superficial dorsal horn of all partially deafferented segments except L5, the spared root segment.Partial deafferentation of the adult rat lumbosacral spinal cord may therefore elicit sprouting from the spared dorsal root and, outside of the dorsal root projection zone, sprouting from the spared descending 5‐HT system. Plasticity of dorsal root projections and of 5‐HT projections occur in different regions; in regions of the increased spared root projection, no increase is seen in 5‐HT projections, suggesting that sprouting in the adult rat spinal cord is regulated, perhaps by competitive or hierarchical mechanisms.
Hypothalamic galanin‐immunoreactive neurons projecting to the posterior lobe of the rat pituitary: A combined retrograde tracing and immunohistochemical study
Authors: Arai R. , Onteniente B. , Trembleau A. , Landry M. , Calas A. 
Published: January 2005

AbstractTo identify the galanin‐immunoreactive neurons projecting to the posterior lobe of the pituitary in the rat hypothalamus, a retrograde tracer (complex of wheat germ agglutinin‐enzymatically inactive horseradish peroxidase‐colloidal gold) was injected into the posterior lobe of the pituitary. Sections of the hypothalamus were treated with a combination of silver enhancement of retrogradely transported tracer and immunohistochemistry of galanin. Of the total number of hypothalamic cells doubly labeled with retrograde tracing and galanin‐immunostaining, 56–60% were found in the supraoptic nucleus, 18–23% in the retrochiasmatic nucleus, 8–10% in the lateral magnocellular portion of the paraventricular nucleus. The ratio of (number of doubly labeled cells/number of galanin‐immunoreactive cells) in each of the above regions was similar to the ratio of (number of retrogradely labeled cells/number of Nissl‐stained cells) in the supraoptic nucleus. Of all retrogradely labeled cells in the hypothalamus, 51–56% also contained galaninlike immunoreactivity.In conclusion: (1) galanin‐immunoreactive fibers in the posterior lobe of the pituitary originate mainly in the supraoptic nucleus, retrochiasmatic nucleus, and lateral magnocellular portion of the paraventricular nucleus, (2) most of galanin‐immunoreactive cells in these regions project to the posterior lobe of the pituitary, and (3) about half the neurons constituting the hypothalamo‐neurohypophyseal system contain galaninlike immunoreactivity.
Distribution of lumbar dorsal root fibers in the lower thoracic and lumbosacral spinal cord of the rat studied with choleragenoid horseradish peroxidase conjugate
Authors: Rivero‐Melián C. , Grant G. 
Published: January 2005

AbstractSpinal cord projections from lumbar dorsal root ganglia (DRGs) were investigated in adult rats following injections of choleragenoid horseradish peroxidase (B‐HRP) into each of the six lumbar DRGs. This method is known to label primarily thick fibers. Labeling was found in all laminae except in the outer part of lamina II. Labeled fibers and terminal‐like structures were found 8–13 segments rostral and 1–5 segments caudal to the injected DRGs.A somatotopic organization was revealed in laminae III, where the labeling seemed to be organized in mediolateral zones. Some of these protruded as fingerlike processes through segments rostral and caudal to the root entry level. An interdigitating pattern for these fingerlike processes was seen between some DRGs, while an extensive overlap was found between other DRGs. Many zones were found to correspond to the known central projections of peripheral sensory nerves supplied by the injected ganglion. This suggests that the central projection of a DRG is highly related to the projections of the peripheral nerves included in the DRG.The projections to lamina IV were organized in a similar manner as in lamina III, even though the projections showed a higher degree of overlap than in lamina III. No clear somatotopic organization was found in laminae V‐IX.Provided that the topographical relationship between central projections of single peripheral nerves and of DRGs correspond to their peripheral projections, the results of this study, together with results of earlier studies suggest that the outlines of dermatomes are highly related to the territories of peripheral nerves included in the dermatomes.
The mechanoreceptive origin of insect tympanal organs: A comparative study of similar nerves in tympanate and atympanate moths
Authors: Yack J. E. , Fullard J. H. 
Published: January 2005

AbstractA chordotonal organ occurring in the posterior metathorax of an atympanate moth, Actias luna (L.) (Bombycoidea: Saturniidae), appears to be homologous to the tympanal organ of the noctuoid moth. The peripheral anatomy of the metathoracic nerve branch, IIIN1b1 was examined in Actias luna with cobalt‐lysine and Janus Green B, and compared to its counterpart, IIIN1b (the tympanal branch), in Feltia heralis (Grt.) (Noctuoidea: Noctuidae). The peripheral projections of IIIN1b1 were found to be similar in both species, dividing into three branches, the second (IIIN1b1) ending as a chordotonal organ. The atympanate organ possesses three sensory cell bodies and three scolopales, and is anchored peripherally via an attachment strand to the undifferentiated membranous region underlying the hindwing alula, which corresponds to the tympanal region of the noctuoid metathorax. Extracellular recordings of the IIIN1b1 nerve in Actias luna revealed a large spontaneously active unit which fired in a regular pattern (corresponding to the noctuoid B cell) and smaller units (corresponding to the noctuoid acoustic A cells) which responded phasically to low frequency sounds (2 kHz) played at high intensities (83–96 dB, SPL) and also responded phasically to raising and lowering movements of the hindwing.We suggest that the chordotonal organ in Actias luna represents the evolutionary prototype to the noctuoid tympanal organ, and that it acts as a proprioceptor monitoring hindwing movements. This system, in its simplicity (consisting of only a few neurons) could be a useful model for examining the changes to the nervous system (both central and peripheral) that accompanied the evolutionary development of insect tympanal organs.
Marginal neurons in the urodele spinal cord and the associated denticulate ligaments
Authors: Schroeder D. M. , Egar M. W. 
Published: January 2005

AbstractMarginal neurons have been described in the spinal cords of a variety of vertebrates including lamprey, reptiles, birds, and mammals but not in amphibians. There has been speculation about a motor function for these neurons but recent experimental evidence in lampreys indicates that they are intraspinal mechanoreceptor neurons. Additional evidence on reptiles and birds demonstrates that the marginal neurons are closely associated with the denticulate ligaments. In the present investigation, we have examined the spinal cords of Necturus, Ambystoma tigrinum, and A. mexicanum with light and electron microscopic techniques. Marginal nuclei were found in the ventrolateral position immediately internal to the pia and to the denticulate ligament. The marginal neurons were scattered in a continuous column of neuropil without segmental accumulation. They were approximately 30 to 50 μm in diameter and fusiform with dendrites extending from the poles, parallel with the length of the spinal cord. Neuronal fingerlike processes, like those found in peripheral mechanoreceptors and in the marginal nuclei of reptiles, were also found in the three species of urodeles studied. The structure of the denticulate ligaments, similar in the three different amphibians, was composed of collagen, elastin, and fibroblasts, all of which were concentrated in the segmental lateral processes.
Amacrine cells of the rhesus monkey retina
Authors: Mariani Andrew P. 
Published: January 2005

AbstractAmacrine cells of the rhesus monkey, Macaca mulatta, were studied in 38 retinas Golgi‐impregnated as whole, flat preparations. By using criteria of dendritic morphology, span of arborization, and level of arborization in the inner plexiform layer, 26 types of amacrine cell ranging in size of dendritic span from 30 μm to 2 mm were identified and listed in increasing size of dendritic span. In some instances, different cell types could be grouped together due to similar morphological features. For example, 1 group, “knotty amacrine cells,” has small cell bodies and a profusion of small, varicose, intertwined processes that span up to 30 μm and are essentially monostratified, but each of the 3 types ends in different strata. Another group is 2 types with about 20 fine radiating processes spanning 1 mm that possess some prominent varicosities. One of these has all of its processes terminating in the innermost stratum of the inner plexiform layer (“spidery”‐type 2 amacrine cells). The other with predominantly similarly ending processes has some that also terminate in the outermost stratum (“spidery”‐type 1 amacrines). These 2 cell types likely correspond to the type 1 and type 2 indolamine‐accumulating amacrine cells in rabbit retina. Other types are individuals which cannot be grouped together but resemble familiar types in cat retina (AII and A13). Other types can be correlated with their putative neurotransmitter (type 1 CA‐dopamine) or transmitter/drug receptor (“spiny”‐benzodiazepine receptor) phenotype. Many types as yet have no known correlate from other Golgi studies or clues as to transmitter or receptor phenotype. This study provides evidence for an unprecedented number of amacrine cell types in the primate retina. The similar morphologies of different types of amacrine cell types within a group suggest other common features within these groups such as neurotransmitter phenotype.
Fields of origin and pathways of the interhemispheric commissures in the temporal lobe of macaques
Authors: Demeter Steven , Rosene Douglas L. , Van Hoesen Gary W. 
Published: January 2005

AbstractThe interhemispheric connections of the cortical areas of the temporal lobe and some neighboring regions were investigated in monkeys (Macaca mulatta and Macaca fascicularis) by anterograde autoradiographic tracing, following injection of radioactively labeled amino acids. The results revealed that the interhemispheric projections of the temporal lobe course through three interhemispheric commissures on their way to the opposite hemisphere. The anterior commissure receives fibers from virtually the entire temporal lobe, including the temporal pole, superior and inferior temporal gyri, and parahippocampal gyrus. Moreover, area 13 of the orbitofrontal cortex, the frontal and temporal subdivisions of the prepiriform cortex, and the cortical and deep nuclei of the amygdala also contribute fibers to the anterior commissure. The heaviest projections arise in the rostral third of the temporal isocortex. These projections become progressively lighter from more caudal regions.By contrast, the corpus callosum receives fibers from the caudal two‐thirds of the temporal lobe, including the temporal pole, superior and inferior temporal gyri, and parahippocampal gyrus. The heaviest projections arise in the caudal third of the temporal lobe and cross primarily in the caudal third of the corpus callosum, including the splenium. Progressively lighter projections arise more rostrally. Fibers from proisocortical and isocortical areas of the posterior parahippocampal gyrus cross in the ventralmost part of the splenium (inferior forceps), whereas cortical areas lateral to the occipitotemporal sulcus give rise to fibers that cross in the caudal part of the body of the corpus callosum and dorsal splenium. The dorsal hippocampal commissure receives fibers exclusively from the parahippocampal gyrus.The fibers of the corpus callosum, hippocampal commissure, and, to a lesser extent, the anterior commissure are intimately associated with the ventricular system as they course through the white matter of the temporal lobe. The fields of origin of the anterior commissure and corpus callosum overlap extensively over the caudal two‐thirds of the temporal lobe. The posterior parahippocampal gyrus is unique in that it gives rise to fibers that cross in all three commissures.
A multiple golgi analysis of the periaqueductal gray in the rabbit
Authors: Meller S. T. , Dennis B. J. 
Published: January 2005

AbstractFour variants of the Golgi method have been used, in the rabbit, to reveal the morphological attributes of neurons within the periaqueductal gray. Of these methods, the Golgi‐Cox version provided the most satisfactory results in terms of both quality and quantity of cell impregnation.In order to make comparison with other descriptions of Golgi characteristics of the periaqueductal gray, statistical analysis was carried out on the distinguishing features of individual neurons, following two different rationales. One method, primarily based on soma characteristics (shape, area, length, and width) and basic features of the primary dendrites (number, length, and number of end‐points) resulted in nine different categories of neurons being recognized: round, ovoid, spindle, pyriform, triangular, pyramidal, rhomboidal, polygonal, and stellate shaped cells.The alternative method principally characterized neurons by an assessment of the degree of dendritic spine development and prominent features of the dendritic tree (number of primary dendrites, length, number of branches, end‐points, and degree of spine development). This approach resulted in nine subgroups within three major classes being identified: three spiny, four moderately spiny, and two aspiny classes (subdivision of each of the groups being resultant on neuronal size and/or the degree of dendritic branching). There was no similarity between the nine groups found by the two methods.Some, though little, correlation of neuron type was evidenced with respect to four zonal subdivisions of the periaqueductal gray complex. It remains to be seen how any of these readily recognizable morphological features, or the subgroups (derived on a statistical basis) into which they fall, might be shown to relate to function.