bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transient increase in expression of GAD65 and GAD67 mRNAs during postnatal development of rat spinal cord
Authors: Ma Wu , Behar Toby , Chang Lisa , Barker Jeffery L. 
Published: January 2005

AbstractGamma‐aminobutyric acid (GABA) is thought to be one of the classic neurotransmitters acting as a developmental signal. To understand the role for GABA in development, we investigated the expression of transcripts encoding two forms of the GABA‐synthesizing enzyme glutamate decarboxylase (GAD65 and GAD67) in the cervical enlargement of the rat spinal cord at successive postnatal days—P0, P7, P14, P21, and P90 (adult)—by using in situ hybridization histochemistry. Cells hybridized with two oligonucleotide probes designed to detect GAD65 and GAD67 mRNAs were widely distributed in all laminae, except in motoneurons of the spinal cord. The integrated densities of hybridization signals were measured across all layers of the gray matter. The relative number of GAD mRNA‐labeled cells was determined within each of four regions: laminae I–;III, laminae IV–VI, laminae VII and VIII, and lamina X. There was a transient increase in both the integrated density and the relative number of hybridized cells between P7 and P14, after which there was a marked decline to adult levels (lowest). An overall decrease in the number of GAD mRNA‐labeled cells was evident in all layers, but a dramatic drop occurred in a subpopulation of cells within ventral portions of the spinal cord. The distribution patterns and postnatal changes in expression of the mRNAs encoding GAD65 and GAD67 were similar and closely paralleled reported changes in the abundance of GAD65 and GAD67 proteins and their product, GABA. Transient increases in GAD mRNA expression during the early postnatal period coincide with, and may be linked to, synapse formation and synapse elimination of the developing spinal cord. © 1994 Wiley‐Liss, Inc.
Neurochemical compartmentalization of the globus pallidus in the rat: An immunocytochemical study of calcium‐binding proteins
Authors: Rajakumar N. , Rushlow W. , Naus C. C. G. , Elisevich K. , Flumerfelt B. A. 
Published: January 2005

AbstractThe globus pallidus external segment forms a major target center of the mammalian striatum which is characterized by neurochemically distinct compartments. The present study was undertaken to determine if a corresponding compartmentalization exists within the globus pallidus external segment in the rat. Immunocytochemical examination of the calcium‐binding proteins parvalbumin and calbindin D28kDa, which are present in neurons of the striatal matrix compartment, was employed. The results indicate three neurochemically distinct compartments within the globus pallidus external segment: (1) an area in the medial aspect of the entire length of the globus pallidus that contains dense immunoreactivity for calbindin D28kDa; (2) a narrow rim at the striatopallidal junction in the rostral two‐thirds of the globus palidus that contains calbindin D28kDa immunoreactivity designated as the “border zone” of the globus pallidus; and (3) an area between these two zones showing very poor immunoreactivity for calbindin D28kDa but containing parvalbumin immunoreactive neurons.The calbindin D28kDa immunoreactive border zone corresponds to the area of the globus pallidus where striatal inputs converge extensively, whereas the rest of the nucleus is involved in segregated, topographically organized pathways. Parvalbumin‐containing neurons are involved in the propagation of striatal output related to striosomal and sensorimotor aspects of basal ganglia function. The present results also indicate that calbindin D28kDa immunoreactivity is completely absent from striosomal neurons and is therefore a useful marker for striatal compartments. © 1994 Wiley‐Liss, Inc.
Early embryonic expression of a 60‐kD glycoprotein in the developing nervous system of the lobster
Authors: Garzino Veronique , Reichert Heinrich 
Published: January 2005

AbstractTo investigate the developmental processes that generate the crustacean nervous system, we used a monoclonal antibody that recognises an antigen that is expressed in the developing embryonic nervous system of the lobster, Homarus gammarus. Expression of this antigen commences early in embryogenesis, occurs in all parts of the embryonic central and peripheral nervous systems, and continues into adulthood. Initial expression in the central nervous system correlates with the onset of neuronal process outgrowth. Light microscopic analysis shows that the antigen is found surrounding the cell bodies and processes of all neurons. Biochemical analysis indicates that the antigen, is a glycoprotein with an apparent molecular weight of 60 kD. Due to the early embryonic onset of its expression, this antigen is a useful cellular label for visualisation of‐ pattern formation in the developing nervous system; this is documented in detail for the developing stomatogastric nervous system. The fact that the 60‐kD antigen is expressed early in embryogenesis throughout the nervous system suggests that it might play an important role in the development of the lobster nervous system. © 1994 Wiley‐Liss, Inc.
Morphological study of the rostral interstitial nucleus of the medial longitudinal fasciculus in the monkey, Macaca mulatta by Nissl, Golgi, and computer reconstruction and rotation methods
Authors: Crossland W. J. , Hu X. J. , Rafols J. A. 
Published: January 2005

AbstractWe have studied the morphology of silver‐impregnated neurons (rapid Golgi technique) in the rostral interstitial nucleus of the medial longitudinal fasciculus (riMLF), a center involved in the control of vertical and torsional saccadic eye movements. This morphological study of riMLF neurons in the rhesus monkey was undertaken to further our understanding of the functional circuitry of the oculomotor system. Our study employed Nissl, Golgi, and computer‐ assisted methods. The cytoarchitectonic boundaries of the riMLF and its relationships to neighboring structures were determined in both Nissl and Golgi preparations. Five (I–V) distinct morphological types of riMLF neurons were distinguished in the Golgi impregnations on the basis of soma size, dendritic size, numbers of primary dendrites, number of dendritic branch points, as well as form, number, and distribution of dendritic appendages. Type I neurons impregnated most frequently and had the most extensive and highly branched dendritic tree. Type II neurons displayed thick dendrites with complex dendritic appendages, but the dendritic tree was much more compact than that of type I cells. Type III and type V cells had fusiform somas and relatively unbranched dendritic trees but differed greatly in size as well as dendritic morphology. The type IV cell was the smallest neuron and had many characteristics of the local interneurons found in other thalamic, subthalamic, hypothalamic, and midbrain centers. The type V was the largest neuron, least frequently impregnated, and found only at rostral riMLF levels. Digitized reconstructions of each type of neuron were rotated by the computer, which revealed that the dendritic trees of types I, III, and V occupy a disk‐like compartment in the riMLF neuropil. In contrast, the trees of types II and IV occupy a roughly spherical compartment. We suggest that three of the cell types are well suited for specific purposes: type II cells for receiving, topographically organized inputs that contain spatial information, type I cells for short‐lead burst neuron output to the motor neurons or other premotor centers, and type IV cells for inhibitory inputs to type I cells. © 1994 Wiley‐Liss, Inc.
Morphological maturation of thalamic neurons as studied in fetal neural transplants
Authors: Cadusseau Josette , Rapisardi Salvatore , Peschanski Marc 
Published: January 2005

AbstractThis study attempts to determine whether fetal thalamic neuroblasts from rat embryos (embryonic age 15 days) labeled with horseradish peroxidase (HRP) can differentiate into their normal dendriticphenotype when transplanted as a cell suspension into a lesioned site in the adult somatosensory thalamus. The HRP labeling provided a Golgi‐like staining of numerous neurons up to 12–14 days after transplantation. There were three main results. (1) As early as 2 days after transplantation three morphologic cell types were observed: Two were bipolar and the third multipolar. These cellular profiles are characteristic of adult ventroposterolateral, reticular, and ventroposteromedial neurons and suggest that transplanted neurons can take shape in the absence of specific arrangements of afferent fibers. (2) The initial stage of dendritic growth was characterized by numerous growing specializations and consisted of a rapid, arborizing growth that appeared to proceed at an accelerated rate relative to normal development. During the later stage, which was characterized by the great reduction of growing specializations, dendritic remodeling resulted in a simpler morphology, and the transplanted neurons did not achieve an adult morphology. (3) Putative axons exhibiting growth cones were present in impressive densities in the transplants, and a number of them grew into the neuron‐depleted host thalamus. A very small number of axons grew into host gray matter outside the lesioned area, indicating that neurodegenerative areas provide a better substrate for neurite outgrowth than, intact tissue. In rare instances axons were visible in the internal capsule, indicating that the biochemical inhibition provided by mature myelin and oligodendrocytes may not be an absolute obstacle to axonal growth. © 1994 Wiley‐Liss, Inc.
Cone bipolar cells as interneurons in the rod, pathway of the rabbit retina
Authors: Strettoi Enrica , Dacheux Ramon F. , Raviola Elio 
Published: January 2005

AbstractIn the mammalian retina, rod signals are transmitted by rod bipolars to the narrow‐field, bistratified (AII) amacrine cell. This neuron, in turn, makes gap junctions with the axonal arborization of cone bipolar cells that reside in the vitreal half (sublamina b) of the inner plexiform layer (IPL). After examining rod bipolars and AII amacrines in the rabbit retina, we have now reconstructed from electron micrographs of continuous series of thin sections the synaptic connections of the axonal arborizations of cone bipolar cells that make the highest number of gap junctions with AII amacrines.These axonal arborizations were narrowly confined to stratum 4 (S4) of the IPL and made ribbon synapses to dyads of postsynaptic‐dendrites that belonged to either ganglion or amacrine cells. In the population of postsynaptic processes, 30% were ganglion cell dendrites. These dendrites were probably originating, at least in part, from on‐center ganglion cells because their course was confined to sublamina b of the IPL. Of the remaining postsynaptic processes, 51.7% belonged to amacrine cells and 18.3% were not identified. Among the postsynaptic amacrine cell processes, 33.3% returned a reciprocal synapse onto the cone bipolar endings. These reciprocal synapses represented 21.3% of the total input onto the axonal arborizations, the remaining fraction (78.7%) arising from a heterogeneous population of amacrine dendrites that were purely presynaptic to the cone bipolars endings. Pre‐ and postsynaptic amacrines were part of several distinct microcircuits which suggest complex local processing of both rod and cone signals.Thus, the cone bipolars that make gap junctions with AII amacrines in sublamina b of the rabbit IPL exhibit a substantial output onto ganglion cells. This fact, in conjunction with our previous observations that in this sublamina ganglion cells receive negligible input from rod bipolars and AII amacrines, demonstrates that in the rabbit cone bipolars represent a necessary link in the pathway followed by rod signals to enter on‐center ganglion cells. Thus, rod and cone signals ultimately share the same integrating mechanisms and converge onto the same set of ganglion cells. © 1994 Wiley‐Liss, Inc.
Peptidies related to the Diploptera punctata allatostatins in nonarthropod invertebrates: An immunocytochemical survey
Authors: Smart D. , Johnston C. F. , Curry W. J. , Williamson R. , Maule A. G. , Skuce P. J. , Shaw C. , Halton D. W. , Buchanan K. D. 
Published: January 2005

AbstractThe allatostatins are a family of peptides isolated originally from the cockroach, Diploptera punctata. Related peptides have been identified in Periplaneta Americana and the blowfly, Calliphora vomitoria. These peptides have been shown to be potent inhibitors of juvenile hormone synthesis in these species. A peptide inhibitor of juvenile hormone biosynthesis has also been isolated from the moth, Manduca sexta; however, this peptide has no structural homology with the D. punctata‐type allatostatins. Investigations of the phylogeny of the D. punctata allatostatin peptide family have been started by examining a number of nonarthropod invertebrates for the presence of allatostatin‐like molecules using immunocytochemistry with antisera directed against the conserved C‐terminal region of this family. Allatostatin‐like immunoreactivity (ALIR) was demonstrated in the nervous systems of Hydra oligactis (Hydrozoa), Moniezia expansa (Cestoda), Schistosoma mansoni (Trematoda), Artioposthia triangulate (Turbellaria), Ascaris suum (Nematoda), Lumbricus terrestris (Ohgochaeta), Limax pseudoflavus (Gastropoda), and Eledone cirrhosa (Cephalopoda). ALIR could not be demonstrated in Ciona intestinalis (Ascidiacea). These results suggest that molecules related to the allatostatins may play an important role in nervous system function in many invertebrates as well as in insects and that they also have an ancient evolutionary lineage. © 1994 Wiley‐Liss, Inc.
Localization of salmon gonadotropin‐releasing hormone mRNA and peptide in the brain of atlantic salmon and rainbow trout
Authors: Bailhache Thierry , Arazam Aïcha , Klungland Helge , Aleström Peter , Breton Bernard , Jego Patrick 
Published: January 2005

AbstractThe decapeptide gonadotropin‐releasing hormone (GnRH) is a key hormone for the central regulation of reproduction. The distribution of salmon GnRH (sGnRH), which is the major form in salmonids, has been studied in different fish species by immunocytochemistry. Discrepancies in data concerning the distribution of sGnRH perikarya led us to investigate this problem in two species, the Atlantic salmon and the rainbow trout, with in situ hybridization of sGnRH messenger, a highly specific molecular tool. By Northern blot analysis, the rainbow trout sGnRH messenger appears to be about 500 bases in length, which is close to those isolated from Atlantic salmon or masu salmon and characterized previously, In situ hybridization with riboprobes generated with Atlantic salmon sGnRH cDNA demonstrated that sGnRH perikarya are restricted to the ventral part of olfactory bulbs, telencephalon, and preoptic area. They are distributed on a nearly continuous line extending from the olfactory bulbs to the preoptic area in both salmonid species studied.Despite the presence of GnRH‐like immunoreactivity in the preoptic magnocellular nucleus (NPOm) and in the tegmentum of the midbrain (MT), the sGnRH mRNA is not present in these two structures. Stained cells in NPOm could be target cells for GnRH and immunoreactive neurons in MT are likely to be chicken GnRH‐II containing cells. Our study not only gives a precise distribution of the sGnRH system in two salmonids, Atlantic salmon and rainbow trout, but also clarifies the ambiguous data published up to now in rainbow trout. © 1994 Wiley‐Liss, Inc.
VGF expression in the brain
Authors: Van Den Pol Anthony N. , Bina Keshavan , Decavel Chantal , Ghosh Prabhat 
Published: January 2005

AbstractVGF is a neuronal polypeptide first identified as a cDNA clone in a gene library from nerve growth factor‐stimulated PC12 cells. In the present paper, the expression of VGF is examined for the first time throughout the adult rat central nervous system with immunocytochemistry and Northern blot analysis. VGF RNA was found in all brain regions studied, including hypothalamus, hippocampus, cerebellum, olfactory bulb, and cortex. In contrast to the relatively strong immunostaining of hypothalamic neurons, the level of VGF RNA expression in the hypothalamus was relatively low in comparison with other brain regions. With the aid of antisera raised against bacterially produced recombinant proteins containing parts of the VGF sequence, immunoreactive neurons were detected throughout the brain, including regions of the olfactory tubercle, caudate‐putamen, thalamus, cortex, amygdala, hypothalamus, mid brain, and hippocampus. VGF‐immunoreactive neurons did not contain detectable amounts of nerve growth factor receptor; other neurons that showed nerve growth factor receptor immunoreactivity expressed no VGF immunoreactivity. The lack of colocalization of VGF and nerve growth factor receptor suggests that, unlike expression in PC12 cells, VGF expression in neurons from the central nervous system does not require nerve growth factor stimulation. Within the hippocampus, the location of VGF‐immunoreactive cells was suggestive of inhibitory interneurons. ‐VGFimmunoreactive axons and terminals were found throughout the brain. These observations extend our earlier work on VGF expression in the hypothalamus to other regions of the brain and support the conclusion that although VGF expression is only detected in subsets of neurons in each brain region, these subsets are widely distributed throughout the central nervous system. © 1994 Wiley‐Liss, Inc.
Structure and function of gustatory neurons in the nucleus of the solitary tract. I. A classification of neurons based on morphological features
Authors: Renehan William E. , Jin Zhigao , Zhang Xueguo , Schweitzer Laura 
Published: January 2005

AbstractPrior investigations in other laboratories have provided convincing evidence that the neurons of the rostral nucleus of the solitary tract (rNST) can be grouped according to their physiological response properties or morphologic features. The present study is based on the premise that the response properties of gustatory neurons are related to, and perhaps governed by, their morphology and, connectivity. In this first phase of our ongoing investigation of structure‐function relationships in the rNST of the rat, we have used intracellular injection of neurobiotin to label individual physiologically characterized gustatory neurons. A total of 63 taste‐sensitive neurons were successfully labeled and subjected to three‐dimensional quantitative and qualitative analysis. A cluster analysis using six morphologic features (total cell volume, soma area, mean segment length, swelling density, spine density, and number of primary dendrites) was used to identify six cell groups. Subsequent analyses of variance and posthoc comparisons verified that each of these six groups differed from all others with respect to at least one variable, so each group was “typified” by at least one of the six morphologic features. Neurons in group A were found to be the smallest neurons in the sample. The cells in group B had small somata and exhibited the highest swelling density of any group. Group C neurons were distinguished by dendrites with long, spine‐free branches. These dendrites were significantly longer than those of any other group except Group F. The neurons in group D had more primary dendrites; than any other group. Group E neurons possessed dendrites with the lowest swelling density but the most spines of any group. The cells in group F were the largest neurons in our sample and possessed the largest somata of any group. Thus, overall cell size and density of dendritic spines and swellings were found to be particularly important variables in this classification scheme. Our preliminary results suggest that the number and density of dendritic spines (as well as other morphologic features) may be related to a given neuron's most effective stimulus, indicating that it will indeed be possible to use the criteria established in the present investigation to derive structure‐function relationships for gustatory neurons in the rNST. © 1994 Wiley‐Liss, Inc.
Hypoxia and electrical stimulation of the carotid sinus nerve induce fos‐like immunoreactivity within catecholaminergic and serotoninergic neurons of the rat brainstem
Authors: Erickson Jeffery T. , Millhorn David E. 
Published: January 2005

AbstractA complete understanding of the neural mechanisms responsible for the chemoreceptor and baroreceptor reflexes requires precise knowledge of the locations and chemical phenotypes of higher‐order neurons within these reflex pathways. In the present study, the protein product (Fos) of the c‐fos protooncogene was used as a metabolic marker to trace central neural pathways following activation of carotid sinus nerve afferent fibers. In addition, immunohistochemical double‐labeling techniques were used to define the chemical phenotypes of activated neurons. Both electrical stimulation of the carotid sinus nerve and physiological stimulation of the carotid bodies by hypoxia induced Fos‐like immunoreactivity in catecholaminergic neurons containing tyrosine hydroxylase or phenylethanolamine‐N‐methyltransferase in the ventrolateral medulla oblongata and, to a lesser degree, in the dorsal vagal complex. Tyrosine hydroxylase/Fos colocalization was also observed in the locus coeruleus and the A5 noradrenergic cell group in pons. Many serotoninergic neurons in nucleus raphe pallidus, nucleus raphe magnus, and along the ventral medullary surface contained Fos‐like immunoreadtivity. In pons and midbrain, Fos‐like immunoreactivity was observed in the lateral parabrachial and Kölliker–Fuse nuclei, the inferior colliculus, the cuneiform nucleus, and in the vicinity of the Edinger–Westphal nucleus, but no catecholaminergic or serotoninergic colocalization was observed in these regions. Although Fos‐labeled cells were observed within and lateral to the dorsal raphe nucleus, few were catecholaminergic or serotoninergic. This study further defines a potential central neuroanatomical substrate for the chemoreceptor and/or baroreceptor reflexes. © 1994 Wiley‐Liss, Inc.
Development of microglia in the quail optic tectum
Authors: Cuadros Miguel A. , Moujahid Amale , Quesada Antonio , Navascués Julio 
Published: January 2005

AbstractThe development of microglia in the quail optic tectum from embryonic day 6 to adulthood was studied by using the QH1 monoclonal antibody. In youngest tecta, microglial cells were scarcely present, but their number rose in subsequent stages. A clear pattern of microglial cell distribution was observable in embryos of 9–16 days. (1) Round cells appeared close to the ventricular layer. (2) Large numbers of ameboid and round labeled cells were seen in the stratum album centrale during development. A gradient of cell density was observable in this layer, as fewer labeled cells appeared in medial regions of the tectum than in lateral regions. (3) Maturing ramified cells were found in layers external to the stratum album centrale, where they increased in number and in branching complexity during development. In adult tecta, almost all microglial cells were of the mature ramified type and were distributed homogeneously in the different tectal layers, although in some layers they had particular morphological features.The distribution of microglia in the developing tectum and in adjacent regions provided insight into the routes of microglial cell invasion of the tectum during development. Apparently, a proportion of microglial cells reached the tectal parenchyma from the meninges and from the ventricular lumen, but the majority of them migrated along nerve fiber tracts from their entry point at the pial surface of the ventromedial caudal tectum. After they reached the stratum album centrale, microglial cells continued their migration toward more external layers, where they differentiated into ramified microglia. © 1994 Wiley‐Liss, Inc.