bluuebunny/crossref_metadata_2025_split huggingface dataset:
GABA and glycine in the central auditory system of the mustache bat: Structural substrates for inhibitory neuronal organization
Authors: Winer Jeffery A. , Larue David T. , Pollak George D. 
Published: January 2005

AbstractThe distribution and morphology of neurons and axonal endings (puncta) were analyzed in auditory brainstem, thalamic, and cortical centers in the mustache bat. The goals of the study were (1) to compare and contrast the location of GABAergic and glycinergic neurons and puncta, (2) to determine whether nuclei containing immunoreactive neurons likewise have a similar concentration of puncta, (3) to assess the uniformity of immunostaining within a nucleus and to consider regional differences that were related to or independent of cytoarchitecture, and (4) to compare the patterns recognized in this bat with those in other mammals.There are nine major conclusions. (1) Glycinergic immunostaining is most pronounced in the hindbrain. (2) In the forebrain, GABA alone is present. (3) Some nuclei have GABAergic or glycinergic neurons exclusively; a few have neither. (4) Although there is sometimes a close relationship between the relative number of immunopositive neurons and the density of the puncta, just as often there is no particular correlation between them; this reflects the fact that many GABAergic and glycinergic neurons project beyond their nucleus of origin. (5) Even nuclei devoid of or with few GABAergic or glycinergic neurons contain relatively abundant numbers of puncta; some neurons receive axosomatic terminals of each type. (6) In a few nuclei there are physiological subregions with specific local patterns of immunostaining. (7) The patterns of immunostaining resemble those in other mammals; the principal exceptions are in nuclei that, in the bat, are hypertrophied (such as those of the lateral lemniscus) amd in the medial geniculate body. (8) Cellular colocalization of GABA and Gly is specific to only a few nuclei. (9) GABA and glutamic acid decarboxylase (GAD) immunostaining have virtually identical distributions in each nucleus.Several implications follow. First, the arrangements of GABA and Gly in the central auditory system represent all possible patterns, ranging from mutually exclusive to overlapping within a nucleus to convergence of both types of synaptic endings on single neurons. Second, although both transmitters are present in the hindbrain, glycine appears to be dominant, and it is often associated with circuitry in which precise temporal control of aspects of neuronal discharge is critical. Third, the auditory system, especially at or below the level of the midbrain, contains significant numbers of GABAergic or glycinergic projection neurons. The latter feature distinguishes it from the central visual and somatic sensory pathways.
Distribution of metabotropic glutamate receptor mGluR5 immunoreactivity in rat brain
Authors: Romano Carmelo , Sesma Michael A. , McDonald Colin T. , O'malley Karen , van den Pol Anthony N. , Olney John W. 
Published: January 2005

AbstractThe receptor mGluR5 is a metabotropic glutamate receptor with messenger RNA abundantly present throughout cortex, hippocampus, and caudate/putamen that is also coupled to phosphatidyl inositide hydrolysis and calcium mobilization. In this study, the distribution of mGluR5 was examined in rat brain by immunocytochemistry. The antibody utilized is highly specific and does not cross react with the most closely related other metabotropic glutamate receptor, as determined by Western blot analysis of nonneuronal cells transfected with metabotropic receptor coding sequences. The receptor mGluR5 is widely expressed with the highest density in olfactory bulb, caudate/putamen, lateral septum, cortex, and hippocampus, as confirmed with both immunocytochemistry and Western blot analysis. Electron microscopic studies in hippocampus and cortex indicate that the labeling is mostly on membranes of dendritic spines and shafts. Light and electron microscopic evidence indicates that some mGluR5 immunoreactivity is located in presynaptic axon terminals, suggesting that mGluR5 may function as a presynaptic receptor.
Prenatal development of rat primary afferent fibers: II. Central projections
Authors: Mirnics Károly , Koerher H. Richard 
Published: January 2005

AbstractThese studies were designed to determine the pattern of initial afferent fiber ingrowth into the prenatal spinal gray matter and the establishment of the topographic organization of the presynaptic neuropil in the dorsal horn. A total of 113 lumbar dorsal root ganglia were labeled with carbocyanine fluorescent dye DiI or DiA in 67 rat embryos and neonatal pups aged embryonic day 13 to postnatal day O (E13–PO).The initial fiber penetration of the lumbar spinal gray began at E15 and was restricted to the segments of entry. Subsequent growth of fibers into gray matter of adjacent segments began approximately one day later, and this delay was continued, about one day for each successive segment. A second wave of ingrowth of putative small‐diameter afferents into the substantia gelatinosa began at E19 and also displayed the same rostrocaudal delay. Fiber ingrowth was specific and occupied the somatotopic area appropriate for the adult, from the earliest stages (E 18) in which dorsal horn laminae could be adequately defined. The somatotopic organization of the presynaptic neuropil in laminae III and IV did not change significantly throughout embryonic development as the amount of overlap between adjacent and non‐adjacent ganglion projections remained constant throughout embryonic development. In addition, it was found that fibers innervating the proximal and distal hindlimb entered the spinal gray simultaneously at E 15 before the innervation of the distal toes was established.The results of these studies indicate that the somatotopic organization of the presynaptic neuropil is established very early in development and requires little refinement to match that seen in the adult. The simultaneous penetration of the fibers originating from the proximal and distal areas of the limb before innervation is complete suggests that this ingrowth may be independent of the establishment of specific peripheral connections.
Accumulation of neuropeptides in the cerebral neurosecretory system of Manduca sexta Larvae Parasitized by the Braconid Wasp Cotesia congregata
Authors: Žitňan Dušan , Kingan Timothy G. , Kramer Steven J. , Beckage Nancy E. 
Published: January 2005

AbstractFifth in star larvae of Manduca sexta that were parasitized by the braconid wasp Cotesia congregata failed to develop after the parasitoid larvae emerged, and these host larvae lingered for 2–3 weeks in a quiescent, nonfeeding state without initiating a larval molt or metamorphosis. This study was focused on the neuroendocrine changes associated with the host's developmental arrest. Immunohistochemical studies suggested that the host brain neurosecretory cells as well as their axon terminals in the corpora cardiaca‐corpora allata complex accumulated multiple neuropeptides. The extent of accumulation in cells and axons increased with time, so that hosts examined 7–14 days after the wasps emerged showed the most intense staining with antibodies against prothoracicotropic hormone, bombyxin, allatotropin, allatostatin, diuretic hormone, eclosion hormone, proctolin, and FMRFamide. Increased levels of prothoracicotropic hormone and FMRFamide‐like peptides in the brains of parasitized larvae were confirmed using Western blots and enzyme‐linked immunosorbent assay (ELISA), respectively. Starvation of the unparasitized larvae induced some accumulation of the neuropeptides; however, the intensity of staining and number of immunopositive cells and axons were in most cases clearly higher in the parasitized larvae. Our results suggest that accumulation of the neuropeptides is associated with developmental arrest of parasitized larvae. Because a similar developmental arrest occurs in a wide range of parasitized insects, our findings may have relevance for many other species. Moreover, these data illustrate the potential value of using parasitized M. sexta larvae as a model for studying the mechanisms governing the rates of neuropeptide expression, processing, packaging, and release, as well as providing a rich source of neuropeptides, thus facilitating their isolation and characterization. © 1995 Wiley‐Liss, Inc.
Octopamine immunoreactivity in the fruit fly Drosophila melanogaster
Authors: Monastirioti Maria , Gorczyca Michael , Rapus Jürgen , Eckert Manfred , White Kalpana , Budnik Vivian 
Published: January 2005

AbstractOctopamine has been proposed as a neurotransmitter/ modulator/ hormone serving a variety of physiological functions in invertebrates. We have initiated a study of octopamine in the fruit fly Drosophila melanogaster, which provides an excellent system for genetic and molecular analysis of neuroactive molecules. As a first step, the distribution of octopamine immunoreactivity was studied by means of an octopamine‐specific antiserum. We focused on the central nervous system (CNS) and on the innervation of the larval body wall muscles. The larval octopamine neuronal pattern was composed of prominent neurons along the midline of the ventral ganglion, whereas brain lobes were devoid of immunoreactive somata. However, intense immunoreactive neuropil was observed both in the ventral ganglion and in the brain lobes. Some of the immunoreactive neurons sent peripheral fibers that innervated most of the muscles of the larval body wall. Octopamine immunoreactivity was observed at neuromuscular junctions in all larval stages, being present in a well‐defined subset of synaptic boutons, type II. Octopamine immunoreactivity in the adult CNS revealed many additional neurons compared to the larval CNS, indicating that at least a subset of adult octopamine neurons may differentiate during metamorphosis. Major octopamine‐immunoreactive neuronal clusters and neuronal processes were observed in the subesophageal ganglion, deutocerebrum, and dorsal protocerebrum, and intense neuropil staining was detected primarily in the optic lobes and in the central complex. © 1995 Wiley‐Liss, Inc.
Intrinsic connections of the rat amygdaloid complex: Projections originating in the lateral nucleus
Authors: Pitkänen Asla , Stefanacci Lisa , Farb Claudia R. , Go G.‐Genevieve , Ledoux Joseph E. , Amaral David G. 
Published: January 2005

AbstractThe amygdaloid complex receives sensory information from a variety of sources. A widely held view is that the amygdaloid complex utilizes this information to orchestrate appropriate species‐specific behaviors to ongoing experiences. Relatively little is known, however, about the circuitry through which information is processed within the amygdaloid complex. The lateral nucleus is the major recipient of extrinsic sensory information and is the origin of many intra‐amygdaloid projections. In this study, we reinvestigated the organization of intraamygdaloid projections originating from the lateral nucleus using the anterograde tracer Phaseolus vulgaris leucoagglutinin (PHA‐L). The lateral nucleus has highly organized intranuclear connections. Dense projections interconnect rostral and caudal levels of the lateral and the medial divisions of the nucleus, and the lateral and medial divisions of the lateral nucleus are also interconnected. The major extranuclear projections of the lateral nucleus are (in descending order of magnitude) to the accessory basal nucleus, the basal nucleus, the periamygdaloid cortex, the dorsal portion of the central division of the medial nucleus, the posterior cortical nucleus, the capsular division of the central nucleus, and the lateral division of the amygdalohippocampal area. The pattern of extranuclear projections varied depending on the rostrocaudal or mediolateral location of the injection site within the lateral nucleus. These findings indicate that intra‐amygdaloid projections originating in the lateral nucleus are both more widespread and more topographically organized than was previously appreciated. © 1995 Wiley‐Liss, Inc.
Morphological characterization of substance P receptor‐immunoreactive neurons in the rat spinal cord and trigeminal nucleus caudalis
Authors: Brown Jessica L. , Liu Hantao , Maggio John E. , Vigna Steven R. , Mantyh Patrick W. , Basbaum Allan I. 
Published: January 2005

AbstractAlthough there is considerable evidence that primary afferent‐derived substance P contributes to the transmission of nociceptive messages at the spinal cord level, the population of neurons that expresses the substance P receptor, and thus are likely to respond to substance P, has not been completely characterized. To address this question, we used an antibody directed against the C‐terminal portion of the rat substance P receptor to examine the cellular distribution of the receptor in spinal cord neurons. In a previous study, we reported that the substance P receptor decorates almost the entire dendritic and somatic surface of a subpopulation of spinal cord neurons. In the present study we have taken advantage of this labeling pattern to identify morphologically distinct subpopulations of substance P receptorimmunoreactive neurons throughout the rostral‐caudal extent of the spinal cord. We observed a dense population of fusiform substance P receptor‐immunoreactive neurons in lamina I at all segmental levels. Despite having the highest concentration of substance P terminals, the substantia gelatinosa (lamina II) contained almost no substance P receptor‐immunoreactive neurons. Several distinct populations of substance P receptor‐immunoreactive neurons were located in laminae III‐V; many of these had a large, dorsally directed dendritic arbor that traversed the substantia gelatinosa to reach the marginal layer. Extensive labeling was also found in neurons of the intermediolateral cell column. In the ventral horn, we found that labeling was associated with clusters of motoneurons, notably those in Onuf's nucleus in the sacral spinal cord. Finally, we found no evidence that primary afferent fibers express the substance P receptor. These results indicate that relatively few, but morphologically distinct, subclasses of spinal cord neurons express the substance P receptor. The majority, but not all, of these neurons are located in regions that contain neurons that respond to noxious stimulation. © 1995 Wiley‐Liss, Inc.
Immunocytochemical localization of the renal neutral and basic amino acid transporter in rat adrenal gland, brainstem, and spinal cord
Authors: Nirenberg Melissa J. , Tate Suresh S. , Mosckovitz Rachel , Udenfriend Sidney , Pickel Virginia M. 
Published: January 2005

AbstractA neutral and basic amino acid transporter (NBAT) cloned from rat kidney was recently localized to enteroendocrine cells and enteric neurons. We used an antibody directed against a synthetic peptide representing a putative extracellular domain of NBAT to determine whether this transporter was also present in other endocrine and neural tissues, including rat adrenal gland, brainstem, and spinal cord. Abundant, highly granular labeling for NBAT was observed in the cytoplasm of chromaffin and ganglion cells in the adrenal medulla. A small population of intensely labeled varicose processes was also seen in both the cortex and the medulla of the adrenal gland. More numerous, intensely labeled varicose processes were detected in brainstem and spinal cord nuclei, including the locus coeruleus, rostral ventrolateral medulla, nuclei of the solitary tract, dorsal motor nucleus of the vagus, and intermediolateral cell column of the thoracic spinal cord. Significant perikaryal labeling for NBAT was only detected in brainstem and spinal cord following intraventricular colchicine treatment, which increased the number, distribution, and intensity of NBAT‐immunolabeled cells. These NBAT‐immunoreactive perikarya were most numerous in the locus coeruleus, rostral ventrolateral medulla, nuclei of the solitary tract, and raphe nuclei. Ultrastructural examination of the nuclei of the solitary tract of normal rats showed that NBAT was localized predominantly to axon terminals. Within these labeled terminals, NBAT was associated with large dense core vesicles and discrete segments of plasma membrane. The observed localization of NBAT suggests that this renal specific amino acid transporter subserves a role as a vesicular or plasmalemmal transporter in monoamine‐containing cells, including chromaffin cells and autonomic neurons. © 1995 Wiley‐Liss, Inc.
Effects of target deprivation on the morphology and survival of adult dorsal column nuclei neurons
Authors: Marty Serge , Peschanski Marc 
Published: January 2005

AbstractDuring development, interaction with target cells plays a critical role in the regulation of survival of afferent neurons. In an attempt to define the role of target cells in the adult central nervous system, the somatodendritic morphology and survival of adult cuneate neurons deprived of their targets by in situ injection of kainic acid in the rat thalamus were studied.In neuron‐specific, enolase‐immunostained sections, a 20% decrease in the mean longest diameter of the labeled cells was detected at 4 months postlesion. This somatic atrophy was accompanied by a loss of distal dendritic arborizations as observed after labeling by intracellular diffusion of horseradish peroxidase. Cytochrome oxidase staining did not reveal detectable alterations of the metabolic activity of these neurons, and an ultrastructural study also failed to demonstrate major changes in the neuronal somata. Cell counts indicated a much delayed death of 25% of the neurons at 10 months postlesion, whereas no neuronal death was detected at 7 months. The glial cells appeared unaltered both in number and in immunolabeling when using OX‐42 antibodies or antiglial fibrillary acidic protein (anti‐GFAP) antibodies.Results obtained in this time‐course study indicate that neuronal death and alteration of the somatodendritic morphology are much delayed events after excitotoxic loss of targets. Somatodendritic atrophy occurs several months postlesion, and neuronal death occurs close to 1 year after lesion. These results suggest that the hypothesis of a necessary continuous trophic support by target cells does not hold as firmly for the adult central nervous system as during development. © 1995 Wiley‐Liss, Inc.
Organization of permanent and transient neuropeptide Y‐immunoreactive neuron groups and fiber systems in the developing hamster diencephalon
Authors: Botchkinal G. I. , Morin L. P. 
Published: January 2005

AbstractThe development of neuropeptide Y‐immunoreactive (NPY‐IR) cell and fiber systems in the hamster diencephalon was studied. Eight perinatal groups of NPY‐IR neurons develop into 12 distinct sets in nuclei of the adult diencephalon and mesencephalon. NPY‐IR neurons of the thalamic precommissural nucleus, nucleus of the optic tract, and olivary pretectal nucleus are derived from the superior group. Those in the adult magnocellular nucleus of the posterior commissure and deep mesencephalic nucleus are from the dorsal group. An arcuate group contributes neurons to the arcuate nucleus and median eminence and a mammillary group transiently exists in the mammillary, region. A medial group gives rise to two sets of neurons, one that migrates to the intergeniculate leaflet and another that develops in the medial nucleus reuniens. A very large ventral group provides NPY‐IR neurons to the adult medial zona incerta and caudal reticular thalamus. Groups of NPY‐IR neurons also appear in the bed nucleus of the stria terminalis and centromedian thalamic nucleus.Superior group neurons may undergo apoptosis. In several groups, neurons become fewer during development, and NPY‐IR may disappear. NPY‐IR neurons of several groups initially migrate away from the neuroepithelial zone with later emergence of a distinct, persistent set of NPY‐IR neurons in the same neuroepithelial region. The data show that neuropeptide content can be used to identify particular sets of neurons early in development, thereby allowing migration patterns to be followed and principles of brain development to be elucidated. © 1995 Wiley‐Liss, Inc.
Cholinergic synaptic circuitry in the macaque prefrontal cortex
Authors: Mrzijak Ladislav , Pappy Miriamma , Leranth Csaba , Goldman‐Rakic Patricia S. 
Published: January 2005

AbstractSurprisingly little is known about the synaptic architecture of the cholinergic innervation in the primate cerebral cortex in spite of its acknowledged relevance to cognitive processing and Alzheimer's disease. To address this knowledge gap, we examined serially sectioned cholinergic axons in supra‐ and infragranular layers of the macaque prefrontal cortex by using an antibody against the acetylcholine synthesizing enzyme, choline acetyltransferase (ChAT). The tissue bound antibody was visualized with both immunoperoxidase and silver‐enhanced diaminobenzidine sulfide (SEDS) techniques. Both methods revealed that cholinergic axons make synapses in all cortical layers and that these synapses are exclusively symmetric. Cholinergic axons formed synapses primarily on dendritic shafts (70.5%), dendritic spines (25%), and, to a lesser extent, cell bodies (4.5%). Both pyramidal neurons and cells exhibiting the morphological features of GABAergic cells were targets of the cholinergic innervation. Some spiny dendritic shafts received multiple, closely spaced synapses, suggesting that a subset of pyramidal neurons may be subject to a particularly strong cholinergic influence. Analysis of synaptic incidence of cholinergic profiles in the supragranular layers of the prefrontal cortex by the SEDS technique revealed that definitive synaptic junctions were formed by 44% of the cholinergic boutons. An unexpected finding was that chohnergic boutons were frequently apposed to spines and small dendrites without making any visible synaptic specializations. These same spines and dendrites often received asymmetric synapses, presumably of thalamocortical or corticocortical origin. Present ultrastructural findings suggest that acetylcholine may have a dual modulatory effect in the neocortex: one through classical synaptic junctions on dendritic shafts and spines, and the other through nonsynaptic appositions in close vicinity to asymmetric synapses. Further physiological studies are necessary to test the hypothesis of the nonsynaptic release of acetylcholine in the Cortex. © 1995 Wiley‐Liss, Inc.