bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of cells expressing galectin‐1, a galactose‐binding receptor, in the rat olfactory system
Authors: Puche A. C. , Key B. 
Published: January 2005

AbstractInteractions between carbohydrate ligands and their receptors play an important role in cell adhesion and migration in many tissues. Cell‐surface carbohydrates that contain terminal galactose have previously been implicated in primary sensory axon growth in the rodent olfactory system. The aim of the present study was to determine whether galectin‐1, a galactose‐binding receptor, was expressed within the rat primary olfactory pathway. Immunohistochemical and in situ hybridisation analyses revealed expression of galectin‐1 by primary sensory olfactory neurons during the major embryonic period of axonogenesis as well as in maturity. In the adult olfactory bulb, galectin‐1 was expressed by both second‐order projection neurons and interneurons and was selectively localised to the synaptic neuropil layers. Mitral cells, the principal postsynaptic target of primary olfactory axons, began expressing this lectin soon after genesis and maintained high levels into adulthood. The expression of galectin‐1 in the primary olfactory pathway and olfactory bulb neuropil suggests a role for this lectin both in the initial formation and in the subsequent maintenance of neuronal connections between the peripheral and the central olfactory neurons as well as between neurons within the bulb. © 1995 Wiley‐Liss, Inc.
Origin of ascending projections to the nuclei of the lateral lemniscus in the big brown bat, Eptesicus fuscus
Authors: Huffman Russell F. , Covey Ellen 
Published: January 2005

AbstractThe nuclei of the lateral lemniscus in the echolocating bat, Eptesicus fuscus, are large and highly differentiated. In each nucleus, different characteristic response properties predominate. To determine whether the dissimilar response properties are due in part to dfferential ascending input, we examined the retrograde transport from small deposits of horseradish peroxidase (HRP) or HRP conjugated with wheat germ agglutinin (WGA‐HRP) in the nuclei of the lateral lemniscus.The intermediate nucleus (INLL) and the two divisions of the ventral nucleus (VNLL) receive almost exclusively monaural input from the anteroventral and posteroventral cochlear nuclei and from the medial nucleus of the trapezoid body. Lesser inputs originate in the lateral nucleus of the trapezoid body and the ventral periolivary area. Although the three monaural nuclei of the lateral lemniscus all receive input from the same set of nuclei, and from the same identified cell types in the cochlear nucleus, there is a difference in the relative proportions of input from these sources. The dorsal nucleus (DNLL) receives input mostly from binaural structures, the lateral and medial superior olives and the contralateral DNLL, with only a minor projection from the coc hlear nucleus. The lateral and medial superior olives project bilaterally; the bilateral projection from the medial superior olive is unusual in that it is found in only a few mammalian species.The results show a segregated pattern of binaural projections to DNLL and monaural projections to INLL and VNLL that is consistent with the binaural response properties found in DNLL and the exclusively monaural response properties found in INLL and VNLL. The differences in response properties between monaural nuclei, however, are not due to input from different nuclei or cell types but may be influenced by differing magnitudes of the constituent ascending projections. © 1995 Wiley‐Liss, Inc.
Development of muscarinic receptor subtypes in the forebrain of the mouse
Authors: Hohmann Christine F. , Potter Elizabeth D. , Levey Allan I. 
Published: January 2005

AbstractCholinergic mechanisms are involved in the regulation of developmental events in the nervous system. Muscarinic cholinergic receptors are thought to be the predominant mediator of cholinergic neurotransmission in the forebrain; however, their developmental role is less well understood. The present study takes advantage of subtype‐specific antibodies to muscarinic receptor proteins to investigate the cellular localization of the subtypes in developing mouse forebrain. Receptor protein expression wag assessed between postnatal day (PND) 5 and adulthood by immunocytochemical methods with antibodies to ml, m2, and m4 receptors, the most abundant subtypes in rodent brain. We have found dramatic developmental changes in the distribution of all three receptors. In the adult mouse, ml and m2 receptor immunoreactivity displayed complementary staining patterns in most forebrain areas with m4 sharing simiarities in pattern with both ml and m2. Furthermore, each receptor was expressed transiently in gray matter areas or fiber bundles at various developmental stages. The m4 receptor was also expressed in developing blood vessels. Such transient immunoreactivity was usually associated with times and areas of dynamic morphogenesis, thus suggesting distinct roles for the receptor subtypes in ontogenetic events. © 1995 Wiley‐Liss, Inc.
Organization of connections between the thalamic reticular and the anterior thalamic nuclei in the rat
Authors: Lozsádi D. A. 
Published: January 2005

AbstractThe thalamic reticular nucleus (TRN) receives topographically organized input from specific sensory nuclei such as the lateral geniculate nucleus. The present study shows this in the rat. However, the pattern of thalamic connections to the limbic reticular sector is unknown.Injecting biocytin into the ventral parts of anteroventral and anteromedial nuclei labeled neurons and axons in the rostral TRN. Filled axon collaterals and their terminals occupied a rectangular sheet in a plane close to the horizontal, and were confined to the inner zone (the medial portion) of the limbic TRN. Retrogradely filled cells were in the middle of the rostral pole in the same horizontal plane, receiving synapses from surrounding labeled boutons. In electron micrographs, thalamic terminals were found to contain round, densely packed synaptic vesicles and formed asymmetrical synapses onto reticular somata and dendritic profiles. Displacing the injection site along the dorso‐ventral and rostro‐caudal axs in the anterior nuclei produced corresponding shifts of antero‐ and retrograde labeling within the inner reticular zone. Projections from the dorsal portions of the anterior nuclei did not follow this pattern. Axons from the anterodorsal nucleus occupied the rostralmost tip of both inner and outer zones of the dorsal limbic sector. In accordance with earlier reports, the limbie sector was found to represent several dorsal thalamic nuclei parallel to each other medio‐laterally. A topography is described for the limbic reticulo‐thalamic connections, suggesting that the rostral TRN is able to influence circumscribed areas of the limbic thalamus. © 1995 Wiley‐Liss, Inc.
Distribution of big tau in the central nervous system of the adult and developing rat
Authors: Boyne L. J. , Tessler A. , Murray M. , Fischer I. 
Published: January 2005

AbstractThe diversity of neuronal morphology and function is correlated with specific expression of various microtubule associated proteins (MAPs). One of the major neuronal MAPs, tau, has multiple isoforms formed as a result of alternative splicing and phosphorylation that are differentially expressed during development. Big tau is a high molecular weight isoform that contains an additional large exon (4a) and is expressed primarily by neurons in the peripheral nervous system (PNS). We cloned the complete 4a exon in an expression vector, isolated the recombinant protein and produced antibodies specific to Big tau that were used to localize Big tau in the developing spinal cord and in the adult central nervous system (CNS). In developing spinal cord, Big tau is first expressed in the central projections of the dorsal root ganglia neurons and in motor neurons at embryonic day 18 and postnatal day 2, respectively. In the adult rat CNS, almost all neurons that extend processes into the PNS express Big tau, including all cranial nerve motor nuclei and central processes of most sensory ganglia; of these ganglia, only the bipolar neurons of the olfactory, Vestibular and spiral ganglia did not express Big tau. Retinal ganglion cells are the only CNS neurons, whose processes remain entirely within the CNS, that express high levels of Big tau. The limited and specific distribution of Big tau is consistent with a role in stabilizing microtubules in axons that are subjected to great shear forces. © 1995 Wiley‐Liss, Inc.
Ultrastructural heterogeneity of enkephalin‐containing terminals in the rat hippocampal formation
Authors: Commons Kathryn G. , Milner Teresa A. 
Published: January 2005

AbstractOpioid peptides, including leu‐enkephalin (LE), are important neuromodulators in the hippocampal formation where they may play a role in learning and memory as well as epileptogenesis. We examined the cellular substrates that underlie the function of LE in each lamina of the rat hippocampal formation by immunocytochemistry at the electron microscopic level in single section analysis. LE‐like immunoreactivity (LE‐LI) was primarily associated with large dense‐core vesicles (80–100 nm), usually found in axons and axon terminals, but was also observed in perikarya and occasionally in dendrites. The morphology and synaptic associations of LE‐LI‐containing terminals were strikingly distinct in each region of the hippocampal formation. In the molecular layer of the dentate gyrus, terminals with LE‐LI were typically small (0.6 μm) and formed primarily asymmetric (excitatory type) synapses on single dendritic spines, which is consistent with the presence of LE in the lateral perforant path. In the hilus of the dentate gyrus, twd types of LE‐containing terminals were present: (1) small round terminals that were heterogeneous in size (0.4–1 μm) and in type of contact formed and (2) larger (3–5 μm) terminals exhibiting the characteristic morphology of mossy fiber boutons that formed asymmetric synapses on spines. This variation in morphology and the type of contact suggests LE may have a heterogeneous influence on diverse hilar interneurons. In the CA3 region of the hippocampus, LE‐LI was localized to large mossy fiber boutons (3–7 μm) that formed multiple asymmetric synapses on complex spiny dendritic processes and often formed puncta adherentia with the shafts of large CA3 pyramidal cell dendrites, indicating that this peptide may be directly released onto pyramidal cells. At the border of stratum radiatum and lacunosum moleculare in the CA1 region of the hippocampus, LE‐labeled terminals averaged 0.8 μm in diameter and often formed symmetric (inhibitory type) synapses on dendritic shafts, which is consistent with a role in disinhibition. In conclusion, these heterogeneous cellular interactions indicate that LE has diverse functional roles and mechanisms of action within each lamina of the hippocampal formation and may directly and indirectly modulate hippocampal cell activity. © 1995 Wiley‐Liss, Inc.
Postnatal maturation of the dopaminergic innervation of monkey prefrontal and motor cortices: A tyrosine hydroxylase immunohistochemical analysis
Authors: Rosenberg David R. , Lewis David A. 
Published: January 2005

AbstractThe mature functional architecture of the primate prefrontal cortex arises during a protracted period of postnatal development. Although catecholaminergic afferents arrive in the primate cortex quite early during fetal development, several lines of evidence suggest that substantial changes in the dopaminergic innervation of prefrontal cortex may occur during postnatal development. In this study, we used immunocytochemical techniques and antibodies against tyrosine hydroxylase, the rate‐limiting enzyme in catecholamine biosynthesis, to examine the precise time course from birth to adulthood of the maturational changes of tyrosine hydroxylase‐labeled axons in prefrontal cortical areas 9 and 46 and primary motor cortex (area 4) of rhesus monkeys.In area 9, the densities of tyrosine hydroxylase‐labeled axons and varicosities in the superficial and deep cortical layers remained relatively constant during postnatal development. In contrast, marked developmental changes in innervation density occurred in the middle cortical layers. For example, in deep layer III, the density of tyrosine hydroxylase‐positive varicosities was relatively low and uniform in animals under 1 month of age but then increased by a factor of three in animals 2–3 months of age. The density of labeled varicosities continued to increase, reaching a peak (sixfold greater than in the youngest animals) in aninuds 2–3 years of age before declining to stable adult levels. Similar laminar‐specific patterns of change also occurred in areas 46 and 4, although regional differences were present in the magnitude and precise time course of these developmental changes.These findings demonstrate that the innervation of monkey frontal cortex by tyrosine hydroxylase‐immunoreactive axons undergoes a protracted, laminar‐specific pattern of change during postnatal development that continues through adolescence and into early adulthood. These developmental refinements may interact with other modifications of cortical circuitry that underlie the functional maturation of these regions. © 1995 Wiley‐Liss, Inc.
Raphe nuclei in three cartilaginous fishes, Hydrolagus colliei, Heterodontus francisci, and Squalus acanthias
Authors: Stuesse Sherry L. , Stuesse David C. , Cruce William L. R. 
Published: January 2005

AbstractThe vertebrate reticular formation, containing over 30 nuclei in mammals, is a core brainstem area with a long evolutionary history. However, not all reticular nuclei are equally old. Nuclei that are widespread among the vertebrate classes are probably ones that evolved early. We describe raphe nuclei in the reticular formation of three cartilaginous fishes that diverged from a common ancestor over 350 million years ago. These fishes are Hydrolagus colliei, a holocephalan, Squalus acanthias, a small‐brained shark, and Heterodontus francisci, a large‐brained shark. Nuclear identification was based on immunohistochemical localization of serotonin and leu‐enkephalin, on brainstem location, and on cytoarchitectonics. Raphe nuclei are clustered in inferior and superior cell groups, but within these groups individual nuclei can be identified: raphe pallidus, raphe obscurus, and raphe magnus in the inferior group and raphe pontis, raphe dorsalis, raphe centralis superior, and raphe linearis in the superior group. Hydrolagus lacked a dorsal raphe, nucleus, but the nucleus was present in the sharks. The majority of immunoreactive cells are found in the superior group, especially in raphe centralis superior, but immunoreactive cells are present from spinal cord to caudal mesencephalon. The distribution and cytoarchitectonics of serotoninergic and enkephalinergic cells are Similar to each other, but raphe nuclei contain fewer enkephalinergic than serotoninergic cells. The cytoarchitectonics of immunoreactive raphe cells in cartilaginous fishes are remarkably Similar to those described for raphe nuclei in mammals; however, the lack of a raphe dorsalis in Hydrolagus indicates that either it evolved later than the other raphe nuclei or it was lost in holocephalan fishes. © 1995 Wiley‐Liss, Inc.
Architecture of individual dendrites from intracellularly labeled thalamocortical projection neurons in the ventral posterolateral and ventral posteromedial nuclei of cat
Authors: Ohara P. T. , Ralston H. J. , Havton L. A. 
Published: January 2005

AbstractThis study provides quantitative descriptions of individual dendrites from electrophysiologically characterized and intracellularly labeled thalamocortical projection (TCP) neurons of the cat ventrobasal complex. One hundred nine dendrites from six ventral posterolateral (VPL) neurons and six ventral posteromedial (VPM) neurons were examined. Measurement of several parameters showed that the individual dendrites were very similar to each other in overall architecture even though they varied greatly in total length and number of dendritic branches. The mean path distance (length from soma to a dendritic tip) was very similar for a dendrites in each group (VPL or VPM) regardless of the number of branches found along the path distance. However, VPL dendrites had a longer mean path distance (VPL = 206 ± 36 μm; n = 51) than VPM dendrites (VPM = 182 ± 29 μm; n = 58; P < 0.001). For all dendrites there was a strong correlation between the stem dendrite diameter and the dendritic length, which allows the estimation of dendritic length from dendrite diameter. Analysis of dendritic scaling shows that branches higher than first order do not follow Rall's ½ power rule, so these neurons cannot be modeled using the equivalent cylinder approximation.The data add to the qualitative descriptions of cat ventrobasal (VB) TCP dendrites currently available and provide a basis for future comparative, developmental, and plasticity studies. Analysis shows that many parameters of cat VB TCP dendrites fall within a narrow range, suggesting that, regardless of differences in length or superficial appearance, these dendrites share a stable underlying architecture. © 1995 Wiley‐Liss, Inc.
Projections from the anterodorsal and anteroveniral nucleus of the thalamus to the limbic cortex in the rat
Authors: Van Groen Thomas , Wyss J. Michael 
Published: January 2005

AbstractThe present study characterized the projections of the anterodorsal (AD) and the anteroventral (AV) thalamic nuclei to the limbic cortex. Both AD and AV project to the full extent of the retrosplenial granular cortex in a topographic pattern. Neurons in caudal parts of both nuclei project to rostral retrosplenial cortex, and neurons in rostral parts of both nuclei project to caudal retrosplenial cortpx. Within AV, the magnocellular neurons project primarily to the retrosplenial granular a cortex, whereas the parvicellular neurons project mainly to the retrosplenial granular b cortex. AD projections to retrosplenial cortex terminate in very different patternsthan do AV projections: The AD projection terminates with equal density in layers I, III, and IV of the retrosplenial granular cortex, whereas, in contrast, the AV projections terminate very densely in layer Ia and less densely in layer IV. Further, both AD and AV project densely to the postsubicular, presubicular, and parasubicular cortices and lightly to the entorhinal (only the most caudal part) cortex and to the subiculum proper (only the most septal part). Rostral parts of AD project equally to all three subicular cortices, whereas neurons in caudal AD project primarily to the postsubicular cortex. Compared to AD, neurons in AV have a less extensive projection to the subicular cortex, and this projection terminates primarily in the postsubicular and presubicular cortices. Further, the AD projection terminates in layers I, II/III, and V of postsubiculum, whereas the AV projection terminates only in layers I and V. © 1995 Wiley‐Liss, Inc.
Intrinsic circuit organization of the major layers and sublayers of the dorsolateral prefrontal cortex in the rhesus monkey
Authors: Kritzer M. F. , Goldman‐Rakic P. S. 
Published: January 2005

AbstractIntrinsic connections are likely to play important roles in cognitive information processing to in the prefrontal association cortex. To gain insight into the organization of these circuits, intracortical connections of major laminar and sublaminar divisions were retrogradely labeled in Walker's area 9 and 46 in rhesus monkeys by using cholera toxin (B‐subunit) conjugated to colloidal gold. Microinjections placed within particular cortical laminae produced unique patterns of retrograde labeling. Injections in layers II/III yielded labeling which was laterally widespread (2–7 mm) in supragranular layers, and more narrowly focused, i.e., conforming to a column, in layers IV–VI. In contrast, local circuits associated with layers IV and Vb displayed a regular, cylindrical organization, whereas intrinsic connections of layer Va were laterally extensive (3–5 mm) in layers III and Va. Finally, injections in layer VI gave rise to a narrow column of cell labeling traversing all layers, augmented by laterally extensive labeling (∼ 7 mm) in layer VI. The intrinsic connections of the prefrontal cortex were arrayed within mediolaterally elongated stripes which were often distributed asymmetrically in either the medial or lateral direction. In addition, labsled cells within these mediolaterally oriented fields were frequently grouped within discrete clusters or narrow bands. The intrinsic connections identified in this study differ from the local circuits of corresponding layers reported for primary visual cortex; the unique intrinsic wiring diagram of the prefrontal cortex may be related to its specialized cognitive and mnemonic functions. © 1995 Wiley‐Liss, Inc.
Developing mossy fiber terminal fields in the rat cerebellar cortex may segregate because of Purkinje cell compartmentation and not competition
Authors: Ji Zhongqi , Hawkes Richard 
Published: January 2005

AbstractMany mossy fiber afferent projections to the rat cerebellar cortex terminate in parasagittal bands. In particular, the anterior lobe ver‐mis of the cerebellum contains alternating bands of mossy fibers from the spinal cord and external cuneate nuclei. The cerebellar cortical efferents, the Purkiwe cells, are also organized in parasagittal bands. These can be revealed by immurkochemical staining for the antigen zebrin II, which is selectively expressed by bands of Purkinie cells. In some cases, the boundaries between mossy fiber terminal fields align with identified transitions between zebrin+/− sets of Purkinie cells, whereas others are located within apparently homogeneous Purkinie cell compartments. Two theories can explain the terminal‐field topography: In one view, mossy fiber terminals segregate during development, because growth cones from different sources compete for common territory. Alternatively, mossy fiber growth cones directly recognize chemically distinct target territories, and activitydependent mechanisms play only minor roles. To explore these issues, two sets of experiments were performed. First, the terminal‐field map of the neonatal spinocerebellar projection was compared to the Purkinie cell compartmentation as revealed by anticalbindin immunocytochemistry. Second, subsets of spinocerebellar mossy fiber afferents were ablated early in postnatal development, and the consequences for the neighboring cuneocerebellar terminal fields were mapped in the adult with reference to the zebrin II+/− compartments. These experiments revealed no evidence that competitive interactions constrain the mossy fiber terminal‐field distribution but, rather, suggest that the organization of the mossy fiber projections follows the oompartmentation of the Purkinie cells. © 1995 Wiley‐Liss, Inc.