bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunocytochemical evidence for the presence of met‐enkephalin and leu‐enkephalin distinct neurons in the brain of the elasmobranch fish Scyliorhinus canicula
Authors: Vallarino Mauro , Bucharles Christine , Facchinetti Fabio , Vaudry Hubert 
Published: January 2005

AbstractImmunohistochemical methods have been used to investigate the distribution of various opioid peptides derived from mammalian proenkephalin in the central nervous system of Scyliorhinus canicula. The results indicate that both Leu‐ and Met‐enkephalin‐immunoreactive peptides are present in the dogfish brain. In contrast, enkephalin forms similar to Met‐enkephalin‐Arg‐Phe or Met‐enkephalin‐Arg‐Gly‐Leu, and mammalian α‐neo‐endorphin, dynorphin A (1–8), dynorphin A (1–13), and dynorphin A (1–17) were not detected.Met‐ and Leu‐enkephalin immunoreactivities were found in distinct neurons of the telencephalon and hypothalamus. In particular, cell bodies reacting only with the Met‐enkephalin antiserum were localized in the preoptic nucleus and in the suprachiasmatic region of the hypothalamus. Conversely, cell bodies reacting only with the Leu‐enkephalin antiserum were localized in the pallium and the nucleus lobi lateralis hypothalami. Several areas of the telencephalon and diencephalon exhibited both Met‐ and Leu‐enkephalin‐like immunoreactivity, but the two immunoreactive peptides were clearly contained in distinct perikarya. The overall distribution of Met‐enkephalin‐immunoreactive elements in the dogfish brain exhibited similarities to the distribution of proenkephalin‐derived peptides previously reported for the brain of tetrapods. The fact that Met‐ and Leu‐enkephalin‐like peptides were detected in distinct neurons, together with the absence of dynorphin‐related peptides, suggests the existence of a novel Leu‐enkephalin‐containing precursor in the dogfish brain. © 1994 Wiley‐Liss, Inc.
Comparative distribution of N‐Acetylaspartylglutamate and GAD67 in the cerebellum and precerebellar nuclei of the rat utilizing enhanced carbodiimide fixation and immunohistochemistry
Authors: Moffett John R. , Palkovits Miklos , Namboodiri M. A. Aryan , Neale Joseph H. 
Published: January 2005

AbstractThe most prevalent peptide in the nervous system, N‐acetylaspartylglutamate (NAAG), specifically activates N‐methyl D‐aspartate (NMDA) receptors and a subclass of metabotropic glutamate receptors. One action of this peptide may be to modulate the release of other neurotransmitters, including gamma‐aminobutyric acid (GABA). The present study describes the cellular distribution of NAAG, relative to GABA, in the cerebellum and precerebellar nuclei as a foundation for further physiological investigations. Numerous cells of origin for mossy fibers, including many of the larger neurons of the pontine nuclei, lateral reticular nuclei, vestibular nuclei, reticulotegmental nuclei, and spinal grey, were moderately to strongly stained for NAAG. Many NAAG‐labeled fibers were clearly visible in the cerebellar peduncles and central white matter. Mossy fibers and mossy endings were among the most prominent NAAG‐immunoreactive elements in the cerebellar cortex. Most neurons in the inferior olive were not stained for NAAG, and only sparse, lightly immunoreactive, climbing fiber‐like endings could be identified in restricted regions of the cortical molecular layer. Purkinje neurons ranged from nonreactive to moderately positive, with the great majority being unstained. Cerebellar granule cells did not exhibit any NAAG immunoreactivity. A population of neurons in the deep cerebellar nuclei was highly immunoreactive for NAAG. Additionally, many neurons of the red nucleus were intensely stained for NAAG. Comparisons with staining for the 67 kD form of glutamic acid decarboxylase in serial sections revealed complementary distributions, with NAAG in excitatory pathways and cell groups, and glutamic acid decarboxylase in inhibitory systems. These findings suggest a significant functional involvement of NAAG in the excitatory afferent and efferent projection systems and provide an anatomical basis for investigations into the interactions of NAAG and GABA in the cerebellum. © 1994 Wiley‐Liss, Inc.
Morphology and synaptic connections of slowly adapting periodontal afferent terminals in the trigeminal subnuclei principalis and oralis of the cat
Authors: Bae Yong Chul , Nakagawa Shinji , Yoshida Atsushi , Nagase Yoshitaka , Takemura Motohide , Shigenaga Yoshio 
Published: January 2005

AbstractPrevious studies suggest that sensory information from primary afferent fibers is processed in a distinct manner in the individual subnuclei of trigeminal sensory nuclear complex. The present study has addressed this issue by using intra‐axonal labeling with horseradish peroxidase to examine the ultrastructure and synaptic organization of axon terminals from slowly adapting (SA) periodontal afferents in the ventral subdivision (Vpv) of principalis and the rostro‐dorsomedial part (Vo. r) of oralis. Our observations are based on complete or near‐complete reconstructions of 139 synaptic boutons in Vpv and 105 in Vo. r.All the labeled boutons contained clear, spherical, synaptic vesicles and were presynaptic to unlabeled dendrites, and they were frequently postsynaptic to unlabeled axon terminals containing pleomorphic synaptic vesicles (P‐endings). The P‐endings frequently formed axodendritic synapses on dendrites which received axodendritic synapses from labeled boutons (synaptic triads). On the basis of the number of contacts, synaptic arrangements associated with the labeled boutons could be subgrouped into simple (one or two contacts), intermediate (three or four contacts), and complex (five or more contacts) types. The labeled boutons varied from round to elongated forms with smooth to more irregular or scalloped contours. The boutons with scalloped contour were much more frequent in the complex type. The boutons of the intermediate type were significantly smaller than the complex type and larger than the simple type.The SA periodontal afferent terminals participated in each type of synaptic arrangements in Vpv, but were mostly of the simple type in Vo. r. The size of labeled boutons was significantly larger in Vpv than in Vo. r. The total number of axodendritic and axoaxonic contacts per labeled bouton was significantly higher in Vpv than in Vo. r. Another difference was the more frequent occurrence of synaptic triads in Vpv than in Vo. r.These observations provide evidence that sensory information from primary afferent fibers is processed in a different manner in the two subnuclei. © 1994 Wiley‐Liss, Inc.
Developmental changes in the laminar termination of a fibre cutaneous sensory afferents in the rat spinal cord dorsal horn
Authors: Fitzgerald M. , Butcher T. , Shortland P. 
Published: January 2005

AbstractIn order to establish the specificity of growth and termination of dorsal root afferents within the developing spinal cord, the central dorsal horn terminals of myelinated sensory afferents were labelled at various stages in the rat from embryonic day (E)18 through to postnatal day (P) 35 using horseradish peroxidase conjugated to choleragenoid (B‐HRP), The preferential labelling of A fibre afferents with this tracer was found to be as clear in the neonate as has been reported for the adult. The results show that while the somatotopic arrangement of A fibre afferent terminals in the dorsal horn is established early in development, the laminar projections are not. Following peripheral nerve or local skin injections of B‐HRP, A fibre terminals were found to project throughout laminae I to V, including laminae II (substantia gelatinosa). This widespread termination was observed consistently until the end of the third postnatal week. After P22 the terminal field becomes restricted to the normal laminae III to V. © 1994 Wiley‐Liss, Inc.
Dynamics of retinotectal synaptogenesis in normal and 3‐eyed frogs: Evidence for the postsynaptic regulation of synapse number
Authors: Norden Jeanette J. , Constantine‐Paton Martha 
Published: January 2005

AbstractQuantitative stereological methods were used to determine if the number, density, and types of synaptic connections formed during development are regulated by presynaptic input or by postsynaptic target cells in the optic tectum of normal and 3‐eyed Rana pipiens tadpoles and frogs. Our analysis indicates that the number and size of synapses is approximately the same in both tecta of 3‐eyed tadpoles and frogs, even though one tectal lobe is receiving input from twice the normal complement of retinal ganglion cells. Moreover, the number and size of synapses in the tectal lobes of 3‐eyed animals did not differ significantly from values determined for normal tadpoles and frogs of the same developmental stage. These data suggest strongly that developing tectal cells regulate the number of synaptic contacts they will form. Differences in several morphological features between singly and doubly innervated tecta, however, including synapse density, distribution and complexity, amount of extracellular space, and number of myelin figures, suggest that the presence of supernumerary input retards tectal maturation. We propose that the noncorrelated activity of retinal ganglion cell terminals in the doubly innervated tectum results in fewer stabilized synapses per unit volume of neuropil and in the delayed maturation of the tectal neuropil. Taken together, our data suggest a complex dynamic interaction between retina and tectum during development. © 1994 Wiley‐Liss, Inc.
Parvalbumin immunoreactivity in the thalamus of guinea pig: Light and electron microscopic correlation with gamma‐aminobutyric acid immunoreactivity
Authors: de Biasi S. , Arcelli P. , Spreafico R. 
Published: January 2005

AbstractThe relationship of the calcium binding protein parvalbumin (PV) with gamma‐aminobutyric acidergic (GABAergic) neurons differs within different thalamic nuclei and animal species. In this study, the distribution of PV and GABA throughout the thalamus of the guinea pig was investigated at the light microscopic level by using immunoperoxidase methods. Intense PV labelling was found in all the GABAergic neurons of the reticular nucleus and in scattered GABAergic neurons in the anteroventral nucleus, whereas GABAergic interneurons in the ventrobasal and lateral geniculate nuclei were not PV labelled.At the electron microscopic level, preembedding immunuperoxidase for PV was combined with postembedding immunogold for GABA. In the ventrobasal nucleus, four types of profiles were recognized: 1) terminals with flattened vesicles and forming symmetric synapses, which were labelled with both PV and GABA and could therefore be identified as afferents from the reticular nucleus; 2) boutons morphologically similar to presynaptic dendrites of interneurons, labelled only with GABA; 3) large terminals with round vesicles and asymmetric synapses, labelled only with PV, which contacted GABAergic presynaptic dendrites in glomerular arrangements and resembled ascending excitatory afferents; and 4) terminals unlabelled by either antiserum.In the ventrobasal nucleus of the guinea pig a double immunocytochemical labelling permits therefore the differentiation of two populations of GABAergic vesicle‐containing profiles, i. e., the terminals originating from reticular nucleus (that are double labelled) and the presynaptic dendrites originating from interneurons (that are GABA‐labelled only). The possibility to differentiate GABAergic inputs from the reticular nucleus and from interneurons can shed light to the functional interpretation of synaptic circuits in thalamic sensory nuclei. © 1994 Wiley‐Liss, Inc.
Histological and ultrastructural localization of the kainate receptor subunits, KA2 and GluR6/7, in the rat nervous system using selective antipeptide antibodies
Authors: Petralia Ronald S. , Wang Ya‐Xian , Wenthold Robert J. 
Published: January 2005

AbstractKainate receptors are found throughout many regions of the brain and presumably contribute to responses of neurons to glutamate and other excitatory amino acids. Two affinity‐purified polyclonal antibodies that recognize the kainate binding subunits, KA2 and GluR6, were made using C‐terminus peptides. A previous study demonstrated that each antibody is specific for its subunit, although antibody to GluR6 recognizes GluR7 to some extent (hence the designation GluR6/7). Vibratome sections immunostained with either antibody showed light to moderate staining in many structures in the brain as well as in cervical spinal cord, dorsal root and vestibular ganglia, and pineal and pituitary glands. Moderate levels were seen in the olfactory bulb, cerebral cortex, caudate/putamen, and hypothalamus, whereas much of the thalamus was stained lightly. In the hippocampus, CA3 pyramidal cells were stained more densely than CA1 pyramidal cells—the difference more evident with antibody to GluR6/7. In addition, neuropilar staining was denset in the stratum lucidum of the CA3 region. In the brainstem, staining was moderate to moderately dense in a number of sensory, motor, and reticular nuclei. The moderately dense staining in the reticulothalamic nucleus and pontine nuclei with antibody to GluR6/7 may represent its recognition of GluR7. In the cerebellum, staining was moderate in granular and molecular layers with antibody to KA2 and in the molecular layer with antibody to GluR6/7, whereas it was moderately dense to dense in the granular layer with the GluR6/7 antibody. Outside of the brain, densest staining was seen localization of immunostaining was examined in the hippocampus, cerebral cortex, and cerebellar cortex. Typically, major staining was in postsynaptic densities apposed by unstained presynaptic terminals with round or mainly round vesicles and in associated dendrites. The light microscope pattern of staining was fairly similar to that of previous [3H]kainate binding and in situ hybridization studies. In addition, comparision with previous studies on distribution of other types of glutamate receptors indicates that KA2 and GluR6/7 are found with various other subunits in many of the same cell populations throughout the nervous system. © 1994 Wiley‐Liss, Inc.
Morphology of retinal axons induced to arborize in a novel target, the medial geniculate nucleus. I. Comparison with arbors in normal targets
Authors: Pallas S. L. , Hahm J. , Sur M. 
Published: January 2005

AbstractFerret retinal axons can be induced to innervate the medial geniculate nucleus (MGN) by a combination of brain lesions early in development. Our previous work suggests that the retinal ganglion cells responsible for this plasticity are W cells. The present study continues this work with a morphological investigation of normal retinal ganglion‐cell axons and retinal ganglioncell axons induced to arborize in the MGN. Retinal axons were bulk filled with horseradish peroxidase placed in the optic tract, and individual axons were serially reconstructed from sagittal sections. The control population consisted of fine‐caliber axons arborizing in the superior colliculus (SC) and in the ventral C laminae of the lateral geniculate nucleus (LGN) of normal ferrets. We also compared the axons in the MGN of lesioned ferrets to intracellularly filled X and Y axons from normal ferrets as reported by Roe et al. ([1989] J. Comp. Neurol. 288:208).We have found that the retino‐MGN axons in the lesioned ferrets do not resemble X or Y axons in normal ferrts in axon diameter, arbor volume, bouton number, or bouton density. However, they do resemble the fine‐caliber, presumed W axons arborizing in the C laminae of the LGN and in the SC of normal ferrets. Thus, this study, in combination with previous studies, suggests strongly that W retinal ganglion cells are responsible for the retinal input to the MGN in lesioned animals. In addition, we find that the retino‐MGN axons are of two types, branched and unbranched, which may correspond to different subtypes of retinal W cells. © 1994 Wiley‐Liss, Inc.
Expression of multiple neuregulin transcripts in postnatal rat brains
Authors: Chen Maio S. , Bermingham‐McDonogh Olivia , Danehy Francis T. , Nolan Colleen , Scherer Steven S. , Lucas Joy , Gwynne David , Marchionni Mark A. 
Published: January 2005

AbstractThe distribution of neuregulin transcripts in rat brains was studied by both RNA blotting and in situ hybridization. Our data demonstrate that multiple neuregulin transcripts are expressed in neurons of the basal forebrain, the hippocampus, the diencephalon, the cerebellum, the brainstem, and the spinal cord. Developmental changes in the distribution of neuregulin transcripts were observed only in the cerebellum and the hippocampus. The intense neuregulin hybridization signals in the brainstem motor and sensory nuclei and the spinal motor neurons are suggestive of a functional involvement of neuregulins in motor and sensory systems. The expression of neuregulins in other parts of the brain also indicates that these factors are involved in a variety of central nervous system functions. © 1994 Wiley‐Liss, Inc.
Characterization of trout galanin and its distribution in trout brain and pituitary
Authors: Anglade Isabelle , Wang Yunxia , Jensen Jorgen , Tramu Gerard , Kah Olivier , Conlon J. Michael 
Published: January 2005

AbstractGalanin was purified from an extract of the stomach of the rainbow trout, Oncorhynchus mykiss, and its primary structure was established as Gly‐Trp‐Thr‐Leu‐Asn‐Ser‐Ala‐Gly‐Tyr‐Leu10‐Leu‐Gly‐Pro‐His‐Gly‐Ile‐Asp‐Gly‐His‐Arg20‐Thr‐Leu‐Ser‐Asp‐Lys‐His‐Gly‐Leu‐Ala. Trout galanin shows six amino acid substitutions compared with pig galanin, but the N‐terminal region (residues 1–14) has been fully conserved. The distribution of galanin‐immunoreactive (GAL‐IR) structures in the trout brain and pituitary was studied via immunohistochemistry. GAL‐IR cell bodies were observed only in the caudal telencephalon, the preoptic region, and the mediobasal hypothalamus. GAL‐IR fibers, however, are widely distributed throughout the brain, with a much lower density in the midbrain and posterior brain than in the tel‐ and diencephalon. Particularly dense innervation of the mediobasal hypothalamus, the ventral and supracommissuralis parts of the caudal telencephalon, and the region above and below the anterior commissure was observed. A heavy innervation of the pituitary was consistently detected. GAL‐IR fibers were present in neurohypophyseal digitations of both the anterior and intermediate lobes with highest density in the region of the proximal pars distalis, where growth hormone and gonadotropic cells are located. Fibers were also seen in digitations of the rostral pars distalis, in particular between the prolactin follicles. The distribution of GAL‐IR neurons in the central nervous system and pituitary of the trout suggests that the peptide may exercise an important role in the regulation of neuroendocrine functions, particularly those related to reproduction. © 1994 Wiley‐Liss, Inc.
Mu, delta, and kappa opioid receptor mRNA expression in the rat CNS: An in situ hybridization study
Authors: Mansour Alfred , Fox Charles A. , Burke Sharon , Meng Fan , Thompson Robert C. , Akil Huda , Watson Stanley J. 
Published: January 2005

AbstractThe μ, δ, and κ opioid receptors are the three main types of opioid receptors round in the central nervous system (CNS) and periphery. These receptors and the peptides with which they interact are important in a number of physiological functions, including analgesia, respiration, and hormonal regulation. This study examines the expression of μ, δ, and κ receptor mRNAs in the rat brain and spinal cord using in situ hybridization techniques. Tissue sections were hybridized with 35S‐labeled cRNA probes to the rat μ (744–1, 064 b), δ (304–1,287 b), and κ (1,351–2,124 b) receptors. Each mRNA demonstrates a distinct anatomical distribution that corresponds well to known receptor binding distributions. Cells expressing μ receptor mRNA are localized in such regions as the olfactory bulb, caudate‐putamen, nucleus accumbens, lateral and medial septum, diagonal band of Broca, bed nucleus of the stria terminalis, most thalamic nuclei, hippocampus, amygdala, medial preoptic area, superior and inferior colliculi, central gray, dorsal and median raphe, raphe magnus, locus coeruleus, parabrachial nucleus, pontine and medullary reticular nuclei, nucleus ambiguus, nucleus of the solitary tract, nucleus gracilis and cuneatus, dorsal motor nucleus of vagus, spinal cord, and dorsal root ganglia. Cellular localization of δ receptor mRNA varied from μ or κ, with expression in such regions as the olfactory bulb, allo‐ and neocortex, caudate‐putamen, nucleus accumbens, olfactory tubercle, ventromedial hypothalamus, hippocampus, amygdala, red nucleus, pontine nuclei, reticulotegmental nucleus, motor and spinal trigeminal, linear nucleus of the medulla, lateral reticular nucleus, spinal cord, and dorsal root ganglia. Cells expressing, κ receptor mRNA demonstrate a third pattern of expression, with cells localized in regions such as the claustrum, endopiriform nucleus, nucleus accumbens, olfactory tubercle, medial preoptic area, bed nucleus of the stria terminalis, amygdala, most hypothalamic nuclei, median eminence, infundibulum, substantia nigra, ventral tegmental area, raphe nuclei, paratrigeminal and spinal trigeminal, nucleus of the solitary tract, spinal cord, and dorsal root ganglia. These findings are discussed in relation to the physiologica functions associated with the opioid receptors.
Effects of retinal lesions upon the distribution of nicotinic acetylcholine receptor subunits in the chick visual system
Authors: Britto L. R. G. , Torrao A. S. , Hamassaki‐Britto D. E. , Mpodozis J. , Keyser K. T. , Lindstrom J. M. , Karten H. J. 
Published: January 2005

AbstractImmunohistochemistry was used in this study to evaluate the effects of retinal lesions upon the distribution of neuronal nicotinic acetylocholine receptor subunits in the chick visual system. Following unilateral retinal lesions, the neuropil staining with an antibody against the β2 receptor subunit, a major component of α‐bungarotoxin‐insensitive nicotinic receptors, was dramatically reduced or completely eliminated in all of the contralateral retinorecipient structures. On the other hand, neuropil staining with antibodies against two α‐bungarotoxinsensitive receptor subunits, α7 and α8, was only slightly affected after retinal lesions. Decreased neuropil staining for α7‐like immunoreactivity was only observed in the nucleus of the basal optic root and layers 2–4 and 7 of the optic tectum. For α8‐like immunoreactivity, slight reduction of neuropil staining could be observed in the ventral geniculate complex, griseum tecti, nucleus lateralis anterior, nucleus lentiformis mesencephali, layers 4 and 7 of the tectum, and nucleus suprachiasmaticus. Taken together with previous data on the localization of nicotinic receptors in the retina, the present results indicate that the β2 subunit is transported from retinal ganglion cells to their central targets, whereas the α7 and α8 subunit immunoreactivity appears to have a central origin. The source of these immunoreactivities could be, at least in part, the stained perikarya that were observed to contain α7 and α8 subunits in all retinoreceipient areas. In agreement with this hypothesis, the β2 subunit of the nicotinic acetylcholine receptors was not frequently found in perikarya of the same areas. © 1994 Wiley‐Liss, Inc.