bluuebunny/crossref_metadata_2025_split huggingface dataset:
Substance P–like immunoreactivity in the lateral cervical nucleus of the owl monkey (Aotus trivirgatus): A comparison with the cat and rat
Authors: Broman Jonas , Blomqvist Anders 
Published: January 2005

AbstractThe location of substance P (SP) in the lateral cervical nucleus (LCN) of monkeys (Aotus trivirgatus), cats, and rats was investigated with immunohistochemical methods. Light microscopic analysis showed that SP‐positive fibers and terminals are evenly distributed throughout the LCN of the monkey and rat, whereas the SP labeling in the LCN of the cat is concentrated in the medial part of the nucleus, with only very sparse labeling in the lateral part. Electron microscopic examination of the monkey LCN revealed the presence of SP‐like immunoreactivity within terminal boutons and unmyelinated axons. The SP‐positive boutons are in synaptic contact with dendrites and, occasionally, cell bodies; they contain densely packed, clear, round synaptic vesicles, as well as dense‐core vesicles.The distribution of SP‐like immunoreactivity in the LCN of monkeys, cats, and rats is similar to that of nociceptive‐responsive neurons demonstrated in electrophysiological experiments. The possible role of the SP‐containing fibers in the transmission of nociceptive information through the LCN is discussed.
Synaptic connections between corticogeniculate axons and interneurons in the dorsal lateral geniculate nucleus of the cat
Authors: Weber A. J. , Kalil R. E. , Behan M. 
Published: January 2005

AbstractAnatomical evidence is provided for direct synaptic connections by axons from visual cortex with interneurons in lamina A of the cat's dorsal lateral geniculate nucleus. Corticogeniculate axon terminals were labeled selectively with 3H‐proline and identified by means of electron microscopic autoradiography. Interneurons in the lateral geniculate nucleus were stained with antibodies that had been raised against gamma aminobutyric acid (GABA).We found that corticogeniculate terminals synapsed with dendrites stained positively for GABA about three times as often as with unstained dendrites. Of the corticogeniculate terminals that contacted GABA‐positive dendrites, 97% made synaptic connections with dendritic shafts. Only 3% synapsed with F profiles, the vesicle‐filled dendritic appendages characteristic of lateral geniculate interneurons. These results suggest that the corticogeniculate pathway in the cat is directed primarily at interneurons and is organized synaptically to influence the integrated output of these cells, rather than the local interactions in which their dendritic specializations participate.
Effects of convergent strabismus on the development of physiologically identified retinogeniculate axons in cats
Authors: Garraghty P. E. , Roe A. W. , Chino Y. M. , Sur M. 
Published: January 2005

AbstractWe have studied the effects of surgically induced convergent strabismus (esotropia) on the morphological development of retinogeniculate X and Y axon arbors in cats. Single axons were recorded in the lateral geniculate nucleus or in the optic tract adjacent to the nucleus, classified physiologically, and injected intracellularly with horseradish peroxidase. The arbors of recovered axons were compared with X and Y axon arbors from normally reared adult cats. Our data demonstrate that while X axon arbors are relatively normal, the arbors of Y axons are profoundly affected by rearing with strabismus. Y axons, whether originating from the deviated or the nondeviated eye, have substantially smaller arbors and fewer boutons in the A‐laminae of the lateral geniculate nucleus compared to Y axons in normal cats. The C‐lamina terminations of contralaterally projecting Y axons in the strabismic cats are unaffected. These results suggest that the postnatal development of retinogeniculate Y axon arbors in the A‐laminae is strongly influenced by abnormalities in postnatal visual experience. Furthermore, the present data suggest that, in addition to intraocular competitive interactions between X and Y axons previously proposed to account for the effects of other rearing conditions, interactions between afferents from the two eyes must also be involved in the development of at least Y axons.
Cytoarchitectonic organization of the spinal cord in the rat: II. The cervical and upper thoracic cord
Authors: Molander C. , Xu Q. , Rivero‐Melian C. , Grant G. 
Published: January 2005

AbstractA laminar cytoarchitectonic scheme of the cervical and upper thoracic segments of the rat spinal cord is presented in which Rexed's principles for the cat are applied. The material examined in the current investigation consists of 50–80 μm‐thick unstained or Nissl‐stained sections, and 2 μm‐thick plastic‐embedded sections stained with paraphenylenediamine. The cytoarchitectonic organization was found to be basically similar to that of the cat. As in our previous study of the cytoarchitectonic organization of the lower thoracic and lumbosacral spinal cord (Molander et al.; J. Comp. Neurol. 230:133–141, '84), the borderlines between the laminae were often found to be ambiguous, suggestive of zones of transition rather than sharp borders. In addition to the laminar scheme, the distribution of certain important cell groups, including the column of Clarke, the central cervical nucleus, the lateral cervical nucleus, the lateral spinal nucleus, and the internal basilar nucleus, is described.
Cellular expression of H and B antigens in the rat olfactory system during development
Authors: Astic L. , Le Pendu J. , Mollicone R. , Saucier D. , Oriol R. 
Published: January 2005

AbstractDevelopmental expression of H and B antigens in the rat olfactory system was studied from the embryonic day 14 up to the postnatal day 30. The H antigen was detected in the olfactory and vomeronasal epithelia as early as fetal day 14, whereas the B antigen first appeared 2 days later. The anti‐H reagent reacted strongly with sensory receptors and weakly with supporting cells in both epithelia, whereas the anti‐B reagent was specific for olfactory receptors. In the main olfactory epithelium, the H antigen was expressed from fetal day 19 by most of the receptor cells, whereas the B determinant was expressed from fetal day 16 to postnatal day 3 by only a few neuroreceptors mostly located near the epithelial surface. After the postnatal day 3, B positive neurons increased in number from the periphery toward the deeper mucosal layers and they were distributed over 3/4 of the epithelial thickness in 15‐ and 30‐day‐old rats. In the main olfactory bulb, a widespread glomerular B staining with variable binding intensity between adjacent glomeruli was already observed at birth. The vomeronasal receptor cells and their axon terminals in the accessory olfactory bulb exhibited a comparable developmental expression of the B antigen. Results suggest that the B antigen could be regarded as a marker of neuronal maturation of both the olfactory and vomeronasal receptor cells; moreover, its first appearance in the receptor cells might be temporally related to the formation of synapses between receptor axons and deutoneurons in the bulb.
Distribution and trajectory of uncrossed axons in the optic nerves of pigmented and albino rats
Authors: Jeffery Glen 
Published: January 2005

AbstractIpsilaterally projecting axons in the optic nerve of the pigmented rat are limited to a roughly retinotopic location within the intraorbital segment of the nerve. However, immediately rostral to the chiasm they are widely dispersed. Here, the way in which this change in distribution arises is analysed by tracing individual fibers retrogradely labelled from the optic tract with horseradish peroxidase (HRP). A comparison is made between albino and pigmented animals.It is demonstrated that the change in this distribution occurs as a consequence of two types of shift in axon trajectory in the intracranial segment. Many axons change their location in the nerve gradually throughout this segment. However, in the proximal half of this region a number of axons also make abrupt changes in their trajectory by travelling at right angles across segments of the mediolateral axis of the nerve. These were seen in both the pigmented and albino animals.Although the albino has an abnormally small ipsilateral retinofugal pathway, the distribution of ipsilateral axons in the optic nerve is very similar to that seen in pigmented animals. Consequently, it is unlikely that position in the prechiasmatic nerve is related to the chiasmatic choice made by axons in this population.
Glutamate‐positive neurons and axon terminals in cat sensory cortex: A correlative light and electron microscopic study
Authors: Conti Fiorenzo , Defelipe Javier , Farin̄as Isabel , Manzoni Tullio 
Published: January 2005

AbstractImmunocytochemical methods were used to perform a correlative light and electron microscopic study of neurons and axon terminals immunoreactive to the antiglutamate (Glu) serum of Hepler et al. ('88) in the visual and somatic sensory areas of cats. At the light microscopic level, numerous Glupositive neurons were found in all layers except layer I of both cortical areas. On the basis of the dendritic staining of Glu‐positive cells, two major morphological categories were found: pyramidal cells, which were the most frequent type of immunostained neuron, and multipolar neurons, which were more numerous in layer IV of area 17 than in any other layer. A large number of Glu‐positive neurons, however, did not display dendritic labelling and were considered unidentified neurons. Counts of labelled neurons were performed in the striate cortex; approximately 40% were Glu‐positive. Numerous lightly stained punctate structures were observed in all cortical layers: the majority of these Glu‐positive puncta were in the neuropil. After resectioning the plastic sections for electron microscopy it was observed that: (1) the majority of neurons unidentifiable at light microscopic level were indeed pyramidal neurons except in layer IV of area 17, where many stained cells were probably spiny stellate neurons. Some Glu‐positive neurons, however, exhibited clear ultrastructural features of nonspiny nonpyramidal cells; (2) all synaptic contacts made by Glu‐positive axon terminals were of the asymmetric type, but not all asymmetric synaptic contacts were labelled. The vast majority of postsynaptic targets of Glu‐positive axons were unlabelled dendritic spines and shafts. The present results provide further evidence that Glu (or a closely related compound) is probably the neurotransmitter of numerous excitatory neurons in the neocortex.
Secondary vestibulocerebellar mossy fiber projection to the caudal vermis in the rabbit
Authors: Thunnissen I. E. , Epema A. H. , Gerrits N. M. 
Published: January 2005

AbstractThe vestibulocerebellar projection in the rabbit has been investigated by the anterograde axonal transport of tritiated leucine, wheat germ‐agglutinated horseradish peroxidase, and Phaseolus vulgaris leucoagglutinin. Mossy fiber terminals originating from all vestibular nuclei, with the exception of the lateral vestibular nucleus of Deiters, were found bilaterally in the lobules X, IX, and VIII of the caudal vermis, without a clear difference in laterality. Most of the vestibular mossy fiber terminals in the caudal vermis originated in the superior and caudal medial vestibular nuclei. Application of the different tracers led to similar results. The labeled terminals were always most numerous in the lobules X and IXd. Small to moderate numbers of mossy fiber terminals were found in the lobules IXa, b, c, and lobule VIII. The greatest change in the density of terminals occurred in most cases around the apex of lobule IXd and not in the depth of the posterolateral fissure between lobules X and IX. The mossy fiber terminals were not distributed equally over the cortex but showed a preference for the proximal parts of the individual lobules. In all experiments, the terminals exhibited a certain degree of clustering in the mediolateral direction, but the clusters were not arranged in longitudinal zones continuous over successive folia.
Sympathetic innervation of the supratentorial dura mater of the rat
Authors: Keller Jeffrey T. , Marfurt Carl F. , Dimlich Ruth V. W. , Tierney Bryon E. 
Published: January 2005

AbstractThe origin, density, and distribution of sympathetic nerve fibers in the supratentorial dura mater of the rat were examined in detail in the current study by using wheat germ agglutinin horseradish peroxidase (WGA‐HRP) retrograde tracing procedures, glyoxylic acid‐induced fluorescence, and dopamine beta‐hydroxylase (DBH) immunocytochemical staining of dural whole mount preparations. Application of WGA‐HRP to the superior sagittal sinus and adjacent areas of the supratentorial dura mater labeled numerous neurons in each of the left and right superior cervical ganglia. Glyoxylic acid and DBH immunocytochemical staining of fixed dural whole mount preparations revealed prominent plexuses of sympathetic nerves about the middle meningeal artery and its branches, about the superior sagittal and transverse sinuses, and „free”︁ within the dura mater, i.e., apparently unassociated with any vasculature. Significantly, in all of these areas, the density of sympathetic innervation revealed in this study was considerably greater than that previously demonstrated by other workers. An impressive population of mast cells also was observed within the dura mater of the glyoxylic acid‐treated preparations. The majority of these cells were perivascular; however, a significant number were also present within the dura unrelated to the vasculature, and occasional cells were seen in close apposition to fluorescent sympathetic nerve fibers. Taken together, the identification of a robust sympathetic plexus and prominent mast cell population associated with a dura mater that also receives significant sensory projections from the trigeminal system raises interest regarding the functional interactions of these elements. These observations warrant further consideration regarding their role in the pathogenesis of vascular headache and head pain.
Intrinsic connections and architectonics of the superior temporal sulcus in the rhesus monkey
Authors: Seltzer Benjamin , Pandya Deepak N. 
Published: January 2005

AbstractThe intrinsic connections of the superior temporal sulcus (STS) in the rhesus monkey were studied by anterograde and retrograde tracer techniques and correlated with a reevaluation of cortical cytoarchitecture. The polymodal region in the upper bank (area TPO) is divisible into four rostral‐to‐caudal architectonic sectors, exhibiting increasing degrees of laminar differentiation and cellularity as one proceeds caudally. These sectors, including the sulcal proisocortex (area Pro), are tied together in a sequence of reciprocal connections. Each rostrocaudal sector of area TPO also has reciprocal connections with the laterally adjacent area TAa, at the upper rim of the sulcus, and medially adjacent areas PGa and IPa, near the depth. A similar architectonic/ connectional organization exists for unimodal vision‐related cortex in the lower bank of the STS. Here a rostrocaudal sequence of reciprocal connections unites area Pro, rostral and caudal divisions of area TEa, and the extrastriate visual area OAa (MT). Area TEa also has reciprocal connections with adjacent segments of area TEm laterally, at the lower rim of the sulcus, and area IPa, medially, in the depth. In both upper and lower banks, caudal‐to‐rostral “for‐wardgoing” connections begin in supragranular layers of cortex and terminate in and around layer IV. Reciprocal, “backgoing” connections take origin from cells in infragranular layers and terminate mainly over the first layer of the caudally adjacent target zone. Orthogonally directed, “side‐to‐side” projections originate in both supra‐ and infragranular layers and terminate diffusely over all layers of cortex.
Calcitonin gene‐related peptide immunoreactivity in the visceral sensory cortex, thalamus, and related pathways in the rat
Authors: Yasui Yukihiko , Saper Clifford B. , Cechetto David F. 
Published: January 2005

AbstractIt has been proposed that calcitonin gene‐related peptide (CGRP) may serve as a major neuromodulator in visceral sensory pathways, but its exact role in the visceral sensory thalamus and cortex has not been determined. We therefore examined the distribution of CGRP‐like immunoreactive (CGRPir) innervation of the insular cortex and the parvicellular division of the ventroposterior nucleus of the thalamus (VPpc) in the rat by using immunohistochemistry for CGRP combined with retrograde transport of the fluorescent dye fluoro‐gold.Modest numbers of CGRPir fibers were distributed in the dysgranular and agranular insular cortex, but few were observed in the granular insular cortex. The density of CGRPir innervation increased caudally along the rhinal fissure and was considerably greater in the perirhinal cortex. When fluorogold was injected into the insular cortex numerous retrogradely labeled neurons were seen in the VPpc, but few of these were CGRPir. Retrogradely labeled CGRPir neurons were, however, seen in the ventral lateral and medial parabrachial (PB) subnuclei. Injection of fluoro‐gold into the perirhinal cortex (which is just caudal to the insular cortex along the rhinal fissure) resulted in many retrogradely labeled CGRPir neurons in the posterior thalamic region, including the subparafascicular, the lateral subparafascicular, and the posterior intralaminar nuclei.The VPpc was heavily innervated by CGRPir fibers but contained few CGRPir cell bodies. Injection of fluoro‐gold into the VPpc resulted in many retrogradely labeled CGRPir neurons in the external medial PB subnucleus bilaterally, but with a contralateral predominance. Smaller numbers of retrogradely labeled CGRPir neurons were also observed in the ventrolateral PB subnucleus, bilaterally with an ipsilateral predominance. These results suggest that CGRP may be a neuromodulator in the ascending visceral sensory pathways from the PB to the VPpc and the insular cortex, but not between the latter two structures.
Autoradiographic localization of thyrotropin‐releasing hormone and substance p receptors in the rat dorsal vagal complex
Authors: Manaker Scott , Rizio Gene 
Published: January 2005

AbstractWe utilized quantitative autoradiography to localize receptors for thyrotropin‐releasing hormone (TRH) and substance P in individual subnuclei of the rat nucleus tractus solitarii (NTS) and the dorsal vagal complex. Within the NTS, TRH receptor concentrations were highest within the gelatinosus and centralis subnuclei and the medial subnucleus rostral to the area postrema, moderate within the intermediate subnucleus and the medial subnucleus adjacent to the area postrema, and low within the ventrolateral and commissural subnuclei and the medial subnucleus caudal to the area postrema. In contrast, substance P receptor concentrations were high throughout the medial subnucleus, moderate in all other subnuclei medial to the tractus solitarius, and relatively low in subnuclei lateral to the tractus solitarius. The dorsal motor nucleus of the vagus contained high concentrations of both TRH and substance P receptors, whereas we observed low TRH and moderate substance P receptors in the area postrema. High TRH and moderate substance P receptors were observed in the adjacent hypoglossal nucleus. In addition, we compared the concentrations of TRH receptors between chloroform‐defatted and nondefatted tissue sections, and noted little effect of white matter tritium quench upon the observed TRH receptor concentrations. These results suggest that neurotransmitter receptors within the rat dorsal vagal complex are organized in a manner consistent with previous cytoarchitectural and hodological partitioning of the NTS and that the distribution of an individual neurotransmitter receptor in the NTS may correspond to the role of that transmitter in modulating autonomic function.
Immunohistochemical localization and biochemical characterization of nerve growth factor receptor in adult rat brain
Authors: Yan Qiao , Johnson Eugene M. 
Published: January 2005

AbstractThe expression of nerve growth factor (NGF) receptor in adult rat brain was studied by immunohistochemistry with a specific anti‐rat NGF receptor monoclonal antibody, 192‐IgG. Intense NGF receptor immunoreactivity (NGFRI) was found in structures known to be NGF responsive, including forebrain cholinergic neurons in medial septum, diagonal band of Broca, and basal nucleus of Meynert; central processes of neural‐crest‐derived sensory ganglion neurons and their innervated nucleus also contained such immunoreactivity. Distinct NGFRI staining was also found in many brain areas and cell types not known to be NGF responsive, including some hypothalamic regions, circumventricular organs, some areas related to the optic system, olfactory glomeruli, ependymal and subependymal cells in some locations, mesencephalic nucleus of the trigeminal nerve, cerebellar molecular layer, central linear nucleus, solitary tract and its nucleus, and inferior olive. The NGFRI in the circumventricular organs was further studied by in vivo labeling of 125I‐ligands. Intravenously injected 125I‐NGF, but not 125I‐cytochrome c, was specifically accumulated in the area postrema. Biochemical study of the NGF receptor showed a major band of molecular weight of approximately 90 KDa in the area postrema, choroid plexus, median eminence, and medial septum with the relative content consistent with that seen by immunohistochemistry. No evidence of a truncated NGF receptor was observed. The results of this study suggest that NGF and its receptor have broader roles in adult mammalian brain than previously thought.
Altered responses to cutaneous stimuli in the second somatosensory cortex following lesions of the postcentral gyrus in infant and juvenile macaques
Authors: Burton H. , Sathian K. , Dian‐hua Shao 
Published: January 2005

AbstractInfant macaques recover tactile abilities better than older animals after somatosensory cortical lesions. To investigate the neural basis of this phenomenon, we ablated the hand representation in primary somatosensory cortex (SI) of infant and juvenile Macaca mulatta and recorded in ipsilateral second somatosensory cortex (SII) a year later. We also made tracer injections to verify the lesion boundaries and to study the connections of SII after the lesion of SI. Similar to the report of Pons et al. (Science 237:417‐420, '87), we found that substantial portions of the SII hand area were unresponsive to cutaneous stimulation of the hand in both age groups. Particularly, there were no cutaneous receptive fields restricted to the digits. Some responses were elicited in each animal by mechanical stimulation of the hand, including a proportion related to cutaneous receptive fields. This proportion was higher in the infants than in the juveniles, which may explain the greater capacity of the infants for recovery of tactile function after SI lesions. The residual somatic drive in the SII hand area of the juveniles was attributable to sparing of parts of areas 3a and 3b. However, in the infants, this explanation was not tenable since the responses noted in SII occurred even after total ablations of the postcentral gyrus. The pattern of corticocortical connections revealed by injections of HRP into the medial margin of the SI lesion and of Fast Blue into SII in one infant confirmed the absence of SI inputs to the region of SII where responses were recorded from the hand. Representations of body parts other than the hand were normally responsive, and their location was consistent with normal somatotopy in SII.