bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cytoarchitecture and visual field representation in area 17 of the tammar wallaby (macropus eugenii)
Authors: Vidyasagar T. R. , Wye‐Dvorak J. , Henry G. H. , Mark R. F. 
Published: January 2005

AbstractTritiated proline was injected into one eye in the tammar wallaby and transported label was studied in the cortex after transneuronal passage through the lateral geniculate nucleus. The autoradiographic label and cytoarchitecture were used to anatomically demarcate the borders of area 17. Electrophysiological recordings from single units were done to obtain a retinotopic map of area 17. Single units in area 17 were found to have orientation sensitivity comparable‐to those seen in placental mammals such as cat and monkey. They could also be classified as simple, complex, and hypercomplex cells. Changes in the cortical areal magnification factor with eccentricity were found to match the drop off in retinal ganglion cell density only along the vertical meridian representation. Along the horizontal meridian, the cortical magnification falls off significantly with eccentricity, whereas the ganglion cell density shows only a mild reduction. Thus central vision, especially the binocular segment, is heavily represented at the cost of the periphery. © 1992 Wiley‐Liss, Inc.
Pattern of substance P‐ and cholecystokinin‐like immunoreactivity during regeneration of the neural complex in the ascidian Ciona intestinalis
Authors: Bollner Tomas , Beesley Philip W. , Thorndyke Michael C. 
Published: January 2005

AbstractThe neural ganglion of ascidians exhibits a novel and rapid pattern of regeneration whereby within approximately 28–35 days of total ablation an entirely new neural complex is formed. In normal adults, neuronal cell bodies expressing substance P‐ (SP‐Li), neurokinin A‐(NKA‐Li), CCK/gastrin‐ (CCK‐Li), and insulin‐like immunoreactivity exhibit a clearly defined pattern of localization in the cortical rind of the ganglion with characteristic long processes arising from the perikarya running throughout the neuropile. CCK‐Li cell bodies are particularly concentrated close to the points of exit of the main nerve trunks. We have used antisera raised against these peptides to monitor the process of regeneration up to postoperative (pa) day 35. Only SP and CGK antisera produced positive staining in the regenerating tissue. Immunoreactive cell bodies first appear following 14 days pa. At this time CCK‐Li neurons are more abundant than SP‐Li neurons and in contrast to the pattern found in the normal adult ganglion, immunoreactive cell bodies are located both peripherally and centrally in the core of the ganglion and processes were rarely seen. Later stages exhibited an increasing number of SP‐Li neurons and at 35 days pa SP‐Li cell bodies clearly predominate. CCK‐Li neurons typically become clustered close to the points of emergence of the anterior nerve roots. The early expression of CCK‐Li and SP‐Li molecules during regeneration is considered in terms of their potential role in development and cell proliferation in the newly forming ganglion. © 1992 Wiley‐Liss, Inc.
Distribution of nerve growth factor‐like immunoreactive neurons in the adult rat brain following colchicine treatment
Authors: Conner J. M. , Varon S. 
Published: January 2005

AbstractUsing immunohistochemical techniques, we have previously localized nerve growth factor (NGF)‐like immunoreactivity in the normal adult rat centralnervous system (CNS) exclusively in the hippocampal mossy fiber region andwithin basal forebrain cholinergic neurons—a cell population believed to be primary NGF consumers within the CNS. In the present investigation, we have attempted to identify potential producers of NGF by pretreating animals with colchicine. Such a treatment would be expected to block microtubule‐assisted neuritic transport mechanisms, thus preventing the accumulation of antigens normally obtained by retrograde transport and forcingthe accumulation of cell products normally exported anterogradely. Forty‐eight hours after colchicine administration within their innervation territories, basal forebrain cholinergic neurons showed a marked loss of NGF‐like immunoreactivity. Conversely, following colchicine treatment, many new populations of NGF‐like immunoreactive cells were detected, several of which have been previously observed with in situ hybridization techniques for NGF mRNA. Many NGF‐like immunoreactive populations, however, were not previously recognized by in situ hybridization methods, including cells of the striatum, reticular thalamic nucleus, paraventricular hypothalamic nucleus, supraoptic nucleus, lateral and medial septum, substantia innominata, and nucleus basalis. Furthermore, evidence is provided that colchicine‐blocked, NGF‐like immunoreactive neurons within the basal forebrain are not cholinergic, thus reinforcing the hypothesis that trophic support for these NGF‐dependent neurons may be derived from distant and local sources. The distinctive distribution of NGF‐like immunoreactive cells observed in this study strongly correlates with the reported distribution of NGF mRNA in CNS neurons, thus suggesting that our antibodies are uniquely recognizing NGF and not other related neurotrophins. © 1992 Wiley‐Liss, Inc.
Growth and regression of thalamic efferents in the song‐control system of male zebra finches
Authors: Johnson Frank , Bottjer Sarah W. 
Published: January 2005

AbstractA serial forebrain pathway in the songbird brain plays a critical role in vocal learning; Area X of the parolfactory lobe (X) projects to the medial portion of the dorsolateral nucleus of the anterior thalamus (DLM), which in turn projects to the lateral magnocellular nucleus of the anterior neostriatum (IMAN). Lesions of this pathway in juvenile birds disrupt vocal development, whereas identical lesions in adult birds do not influence the production of already learned song. During the course of vocal learning, IMAN undergoes a phase of massive neuronal loss, whereas the neuronal population of X more than doubles. In the present study, the development of neuron number in DLM was analyzed and found not to change during the course of vocal learning. Anterograde DiI labeling of DLM efferent fibers was then used to analyze the morphological development of this projection in relation to both the loss of neurons from IMAN and the loss of the ability of X‐DLM‐IMAN lesions to influence vocal production. We found that DLM axons arrive within IMAN by 15 days of age, prior to both the loss of neurons from IMAN and the onset of vocal production. The volume of anterograde DiI label over IMAN did not change between 15 and 20 days of age, but this volume more than doubled between 20 and 35 days of age. During this phase of exuberant growth, anterograde label matched the dorsal border of IMAN but extended beyond all other borders of IMAN into a surrounding “shell” of parvicellular neurons. By adulthood, the volume of both IMAN and anterograde DiI label declined substantially, but anterograde label continued to fill a parvicellular region of neostriatum surrounding all but the dorsal border of IMAN. Because DLM neuron number is stable during vocal development, these changes must reflect the growth and regression of some aspect(s) of DLM axonal morphology. Rearrangement of DLM axonal arborization may therefore be an important factor in the functional development of the X‐DLM‐IMAN pathway. © 1982 Wiley‐Liss, Inc. © 1992 Wiley‐Liss, Inc.
Entorhinal cortex of the human, monkey, and rat: Metabolic map as revealed by cytochrome oxidase
Authors: Hevner Robert F. , Wong‐Riley Margaret T. 
Published: January 2005

AbstractThe entorhinal cortex (EC) is a medial temporal lobe area involved in memory consolidation. Results from previous studies suggest that the upper layers of the EC may be organized into anatomical‐neurochemical modules associated with pathways through the neuron clusters in layers II and III. To study metabolic patterns in the EC and to look for correlates of the proposed modules, we examined the distribution of cytochrome oxidase (CO) in the human, monkey, and rat EC. CO is a mitochondrial enzyme that has been used to study modules in other cortical areas.In all three species, the neuron clusters in layers II‐III were darkly CO‐reactive, whereas most of the neuropil between clusters was lightly or moderately CO‐reactive. However, some neuropil regions directly adjacent to the neuron clusters were also darkly CO‐reactive, especially in the human; these neuropil areas included portions of layers I and II. In tangential sections through layers I‐II, the areas of dark staining formed a consistent pattern, comprised of partially interconnected islands and stripes associated with the neuron clusters. In the EC from one human hemisphere, ∼200–250 CO‐reactive layer II islands were present. EC layers other than I‐III also showed characteristic CO staining intensities, but no evidence of modularity.Our results indicate that CO staining labels distinct compartments related to the neuron clusters in the upper EC layers. We propose that these compartments may represent modules for cortical processing, analogous to the CO‐labeled modules in some other areas of cortex. © 1982 Wiley‐Liss, Inc. © 1992 Wiley‐Liss, Inc.
Development of GABA‐immunoreactivity in the neocortex of the mouse
Authors: Del Rio Jose A. , Soriano Eduardo , Ferrer Isidro 
Published: January 2005

AbstractThe prenatal and postanatal development of GABAergic elements in the neocortex of the mouse was analyzed by GABA‐immunocytochemistry. Radial distribution of cells and laminar numerical densities were calculated at each developmental stage to substantiate qualitative observations. The first immunoreactive neurons were observed in the cortical anlage at embryonic day 12‐embryonic day 13 (E12–E13) in the primitive plexiform layer. At following prenatal stages (E14–E19), most GABA‐positive neurons were present in the marginal zone, subplate, and subventricular zone. GABA‐immunoreactivity in the cortical plate appeared early (E14), although the complete maturation of its derivatives was achieved postnatally. At prenatal stages we noted a well‐developed system of immunopositive fibers in the subplate. As indicated by the direction of growth cones, most of these fibers had an extracortical origin and invaded the cortex laterally through the internal capsule and striatum. In rostral and middle telencephalic levels, fibers originating in the septal region contributed to the cingulate bundle. Presumably corticofugal fibers and callosal axons were also noticed. At postnatal stages the maturation of GABA‐immunoreactivity appeared to be a complex, long‐lasting process, in which the adult pattern was produced at the same time as the appearance of certain regressive phenomena. Thus, between postnatal day 0 and postnatal day 8 (P0–P8), GABA‐positive populations disappeared from the subventricular zone, marginal zone and to a lesser extent from the subplate. At the same ages we noticed the presence of morphologically abnormal, GABA‐immunoreactive neurons in the subventricular zone and subplate which are interpreted as correlates of neuronal degeneration. Most GABA‐positive subplate fibers also disappeared whereas GABA‐immunoreactive axons were seen in the cingulate bundle until the adult stage. In the derivatives of the cortical plate, the maturation of GABA‐immunoreactive elements progressed according to the “inside‐out” gradient of cortical development, with the important exception of layer IV, which was the last layer to exhibit an adult‐like appearance. Within each layer deriving from the cortical plate (layers VIa to II–III), GABA‐immunoreactivity showed a protracted maturation in which the first GABA‐positive cells were detected a few days after cell birth but substantial numbers of neurons began to express GABA considerably later. The later phase occurred concurrently with the maturation of GABA‐positive axonal plexuses. These results suggest that different GABA‐positive populations show different developmental regulation of GABA expression during cortical ontogenesis. © 1992 Wiley‐Liss, Inc.
Central projections of auditory nerve fibers of differing spontaneous rate, II: Posteroventral and dorsal cochlear nuclei
Authors: Liberman M. Charles 
Published: January 2005

AbstractResponse properties of auditory nerve fibers (ANFs), including threshold sensitivity, vary systematically with spontaneous discharge rate (SR) (Liberman, M.C.: J. Acoust. Soc Amer. 63:442–455, 1978). Thus, an understanding of the mechanisms underlying signal transformation in the cochlear nucleus (CN) must include a description of any SR‐based difference in ANF projections. This study is the second of a pair describing the CN projections of intracellularly labeled ANFs of known SR, the first of which summarized projection to the anteroventral CN (Liberman, M.C.: J. Comp. Neurol. 313:240–258, (1991). For each swelling from each labeled fiber, the position (within CN subdivisions), the size, and the type of cell contacted (if determinable) was noted: roughly one in four labeled swellings appeared in intimate contact with the soma or proximal dendrites of a CN cell. In all such cases, cell size and swelling size were measured. As reported for auteroventral cochlear nucleus, the ANF innervation of the small‐cell regions of posteroventral CN (PVCN) was almost exclusively by low‐and medium‐SR fibers. Other significant SR‐based trends in ANF projections included (1) a tendency for high‐SR fibers to contact larger cells in PVCN, (2) a meager projection of low‐ and medium‐SR fibers to octopus cells, and 3) a tendency in the dorsal CN (DCN) for low‐SR terminals to end closer to the fusiform cell layer than high‐SR terminals. There were no significant SR‐based difference in ANF swelling sizes in any subdivision. A consideration of the average cell sizes, ANF swelling sizes and estimated numbers of ANFs of different CF and SR converging on each CN cell help explain some of the differences in response transformation associated with different cell types in the CN. © 1993 Wiley‐Liss, Inc.
Immunohistochemical identification of trigeminal ganglion neurons that innervate the mouse cornea: Relevance to intercellular spread of herpes simplex virus
Authors: LaVail Jennifer H. , Johnson Welkin E. , Spencer Lawrence C. 
Published: January 2005

AbstractInoculation of the scarified cornea with herpes simplex virus (type 1) leads to herpetic infection of trigeminal ganglion cells. A recent study of the susceptibility of ganglion cells revealed that there may be at least four populations of trigeminal ganglion cells that are infectable by herpes. Two classes were identified by their neuropeptide content: Substance P or calcitonin gene‐related peptide. One class was identified by its affinity for a monoclonal antibody, SSEA‐3. The fourth class was recognized by its common affinity for both the monoclonal antibody LD2 and for the lectin Bandeiraea simplicifolia isolectin. However, there has been no direct evidence of which types are infected directly as a result of retrograde transport from the corneal site and which may be infected by cell‐to‐cell spread. The aim of this study was to determine which classes of neurons, which are known to become infected with HSV after ocular inoculation, supply corneal innervation.We have identified four classes of trigeminal ganglion neurons that supply axons to the central cornea of the mouse, on the basis of their ability to transport Fluoro‐Gold retrograde from axons in the central corneal epithelium and stroma. About 40% of the neurons that innervate the cornea contain Substance P or calcitonin gene‐related peptide; about 60% of the neurons that innervate the cornea react with the monoclonal antibody SSEA‐3. About 36% of all neurons in the whole ophthalmic division react with the LD2 or Bandeiraea simplicifolia isolectin, and Fluoro‐Gold labels only 2% of them. Thus, the population of LD2/Bandeiraea Simplicifolia Isolectin neurons that innervates the cornea represents less than 1% of the total neurons in the ophthalmic division, although it constitutes about 20% of the infected cells in that division at three days after viral inoculation. We conclude that most of the LD2/Bandeiraea simplicifolia isolectin‐positive ganglion cells that are infected with herpes at 3 days are infected as a result of HSV spread from nearby cells in the ganglion or proximal trigeminal root. Neurons labeled with antibodies to Substance P, calcitonin gene‐related peptide, or α‐SSEA‐3 that are primarily infected may be sources of the cell‐to‐cell spread of virus. © 1993 Wiley‐Liss, Inc.
Development of the dorsal root ganglion in a teleost, Oreochromis mossambicus (Peters)
Authors: Laudel Timothy P. , Lim Tit‐Meng 
Published: January 2005

AbstractThe precursor crest cells of the spinal dorsal root ganglia (DRG) in the tilapia, Oreochromis mossambicus, were analysed by HNK‐1 antibody staining, scanning electron microscopy, and DiI labeling techniques. The ontogeny of the DRG was followed in the embryos and young fry of the fish. Neural crest cells which contribute to the formation of the DRG were observed to commence their migration in the trunk region after 40 hours postfertilization. They do not penetrate the somites but travel through the space between the neural tube and the somite. Crest cells destined to become the DRG accumulate at the midsomitic region where the ventral root exits. At 50 to 80 hours postfertilization, they differentiate and become bipolar sensory cells. The DRG continues to grow and develop right through hatching at 115 hours. During the early larval stages, crest cells accumulate around the ventral root and the DRG eventually fuses with the motor root, giving rise to a situation in which the DRG contains not only the sensory cells but also motor fibres. The mixed nature of the DRG was confirmed by HRP retrograde labeling. We believe that this is the first report in describing the formation of the DRG in a teleost. © 1993 Wiley‐Liss, Inc.
Effect of wound healing and tissue transplantation on the navigation of axons in organ‐cultured embryonic chick eyes
Authors: Halfter Willi 
Published: January 2005

AbstractWound closure and repair of embryonic neuroepithelium were studied in organ‐cultured embryonic retinae. Eyes from 3 to 4‐day‐old embryos were cultured after removing pieces of retinal tissue. During the subsequent 24 hours of incubation, the 150 to 200 μm wide holes in the retina closed completely. Histological studies showed that the wound closure was not accomplished by cell migration or cell proliferation, but by an approximation of the wound edges mediated by extracellular matrix fibrils of the vitreous body. The wound contraction facilitated the integration of transplants into the retinal neuroepithelium with a perfect alignment of the implants with the host at the vitreal surface. Within 24 hours, a continuous inner limiting membrane between transplant and host retina was established. The effect of wound healing and tissue transplantation on the navigation of optic axons in the retina was investigated. The wound contraction in the retina caused the optic axons near the lesion site to grow to the wound center, where the axons traversed the retina and formed a neuroma at the ventricular side, resembling the organization of axons at the optic disc. In the transplantation paradigm, axons from the host retina migrated into the transplant and vice versa. However, due to the wound contraction around the transplant, most axons grew into the interface between the transplant and host tissue. 1993 Wiley‐Liss, Inc.
Fine structure of calcitonin gene‐related peptide immunoreactive synaptic contacts in the thalamus of the rat
Authors: Williamson Andrew M. , Ralston Henry J. 
Published: January 2005

AbstractRecent studies have shown a prominent calcitonin gene‐related peptide immunoreactive (CGRP‐ir) pathway extending from the external medial and external lateral para‐brachial nuclei to the area surrounding and including the gustatory nuclei in the thalamus, and the cortex and amygdala. The function of the CGRP‐ir pathway is not completely understood, but may be involved with the processing of both nociceptive and gustatory information in the thalamus.The purpose of this study was to characterize the nature of the CGRP‐ir synaptic contacts in the gustatory nucleus. Electron microscopic examination of CGRP‐ir synaptic contacts revealed two classes of CGRP‐ir terminals. One class, which was large, formed asymmetric synaptic contacts on dendritic appendages, had many small, round synaptic vesicles, and heavy patches of reaction product which obscured any underlying organelles. Since similar terminals in unstained tissue contained large numbers of dense‐cored vesicles, it was concluded that CGRP‐ir was contained predominantly in dense‐cored vesicles.A second class of CGRP‐ir terminals was smaller and made either asymmetric or symmetric synaptic contacts. Both symmetric and asymmetric small terminals contained small, round synaptic vesicles and fewer patches of dense reaction product. Several of the CGRP‐ir terminals making symmetric contacts also contained pleomorphic vesicles. There were very few contacts on cell bodies. There were no contacts on other CGRP‐ir elements, somal or dendritic, or on axon terminals. None of the CGRP‐ir terminal elements were postsynaptic to unlabeled terminals. Axons containing CGRP‐ir were primarily unmyelinated, but a few myelinated axons were also seen. © 1993 Wiley‐Liss, Inc.
Localisation of mRNA encoding the protein precursor of galanin in the monkey hypothalamus and basal forebrain
Authors: Evans Helen F. , Huntley George W. , Morrison John H. , Shine John 
Published: January 2005

AbstractThe hypothalamic and basal forebrain sites of synthesis of preprogalanin mRNA were identified in three adult monkeys (Macaca fascicularis) by in situ hybridisation performed with a radiolabelled cRNA probe transcribed from human preprogalanin cDNA. With stringent hybridisation conditions, the cRNA probe was hybridised to free‐floating sections containing structures contiguous with the rostral hypothalamus through to the caudal limit of the hypothalamus as defined by the mammillary bodies. Specific hybridisation of the preprogalanin cRNA probe occurred throughout the hypothalamus but was particularly intense in the arcuate, paraventricular (parvicellular and magnocellular portions), and dorsomedial nuclei. Moderate hybridisation was found in the periventricular nucleus and scattered hybridisation in the medial preoptic nucleus. The medial preoptic area and the anterior and lateral hypothalmic areas showed moderate to intense hybridisation in scattered cells. A few cells in the tuberal portion and dorsal cap of the anterior portion of the supraoptic nucleus were labelled. Isolated cells were also labelled in the zona incerta. There was little labelling in the dorsal hypothalamic area but moderate labelling in the posterior hypothalamic area. Structures contiguous with the rostral hypothalamus including the diagonal band of Broca, bed nucleus of stria terminalis, substantia innominata, and basal nucleus of Meynert showed intense hybridisation. These data indicate a widespread distribution of preprogalanin mRNA in the monkey hypothalamus. A comparison with the previously reported distribution of preprogalanin mRNA in the rat, as well as with the distribution of galanin‐like immunoreactivity in the rat and human, suggests some important species differences. Of particular interest were differences in the supraoptic, suprachiasmatic, and dorsomedial nuclei. The intense hybridisation throughout the paraventricular nucleus and in the rostral arcuate nucleus suggests that galanin may play a role in the regulation of both posterior and anterior pituitary function. © 1993 Wiley‐Liss, Inc.