bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ultrastructural evidence for a paucity of projections from the lumbosacral cord to the pontine micturition center or M‐region in the cat: A new concept for the organization of the micturition reflex with the periaqueductal gray as central relay
Authors: Blok Bertil F. M. , De Weerd Henk , Holstege Gert 
Published: January 2005

AbstractInformation concerning the rate of bladder filling is determined by receptors in the bladder wall and conveyed via afferent fibers in the pelvic nerve to sensory neurons in the lumbosacral cord. It was assumed that this information is relayed from the lumbosacral cord to a medial cell group in the dorsolateral pontine tegmentum, called the M‐region, the pontine micturition center, or Barrington's nucleus. The M‐region, in turn, projects via long descending pathways to the sacral parasympathetic motoneurons. In the present electron microscopic study, it was investigated in cats whether monosynaptic projections from lumbosacral neurons to the M‐region indeed exist. Wheat‐germ agglutinin‐horseradish peroxidase injections were made into the lumbosacral cord. Many retrogradely labeled dendrites and somata were found in the M‐region, but no labeled terminals were found on retrogradely labeled dendrites or somata. Only a small number of anterogradely labeled terminals, which were filled with mainly round vesicles, contacted unlabeled dendrites in the M‐region. In contrast, many more anterogradely labeled terminals, which were filled with mainly round and, to a limited extent, dense core vesicles and with asymmetrical synapses, were found on dendrites in the lateral part of the periaqueductal gray (PAG). Previously (Blok and Holstege [1994] Neurosci. Lett. 166:93–96), it was demonstrated that the lateral part of the PAG contains neurons projecting to the M‐region.A concept for the central organization of the micturition reflex is presented in which ascending projections from the lumbosacral cord convey information on bladder filling to the PAG. When the bladder contains so much urine that voiding is necessary, the PAG, in turn, triggers the M‐region. The M‐region, however, also receives afferents from the preoptic area, which might be involved in phe final decision to start micturition. © 1995 Wiley‐Liss, Inc.
Thyrotropin‐releasing hormone‐immunoreactive varicosities synapse on rat phrenic motoneurons
Authors: Murphy Susan M. , Pilowsky Paul M. , Sun Qi‐Jian , Llewellyn‐Smith Ida J. 
Published: January 2005

AbstractThe relationship between retrogradely labelled or intracellularly filled phrenic motoneurons and varicosities containing thyrotropin‐releasing hormone immunoreactivity was investigated in rats by light and electron microscopy. Phrenic motoneurons were identified via retrograde tracing from the dirphragm with cholera toxin B subunit, which was followed by immunocytochemistry to visualise retrogradely labelled motoneurons and thyrotropinrpleasing hormone‐immunoreactive nerve fibres in their vicinity. At the light microscopic level, varicose thyrotropin‐releasing hormone‐immunoreactive nerve fibres were distributed sparsely in the phrenic motor nucleus, with some axons surrounding retrogradely labelled motoneurons. In separate intracellular experiments, four phrenic motoneurons identified by antidromic activation from the C5 phrenic nerve root were subsequently filled with Neurobiotin, and nerve fibres that contained thyrotropin‐releasing hormone immunoreactivity were identified by immunocytochemistry. The numbers and locations of thyrotropin‐releasing hormone‐immunoreactive varicosities that were closely apposed to the intracellularly labelled motoneurons were mapped using a camera lucida technique. Close appositions by thyrotropin‐releasing hormone‐immunoreactive varicosities were seen on somata as well as on proximal and distal dendrites. The closely apposed varicosities were usually present in tight clusters, which were formed by single varicose axons. However, the distribution was nonuniform, in that some dendrites did not receive any close appositions. Ultrastructural analysis of random ultrathin sections through retrogradely labelled neurons showed that varicosities with thyrotropin releasing hormone immunoreactivity made 1.8% of all synapses and direct contacts on somata and 2.3% of synapses and contacts with dendrites of the retrogradely labelled phrenic motoneurons. The results of these experiments suggest that thyrotropin‐releasing hormoneimmunoreactive varicosities provide similar numbers of inputs to both the somata and dendrites of phrenic motoheurons. These thyrotropin‐releasing hormone‐containing inputs seen via light and electron microscopy could modulate the excitability of phrenic motoneurons. © 1995 Wiley‐Liss, Inc.
Distribution of acidic fibroblast growth factor mRNA‐expressing neurons in the adult mouse central nervous system
Authors: Kresse Adelheid , Pettersson Ralf , Hökfelt Tomas 
Published: January 2005

AbstractThe distribution of acidic fibroblast growth factor (aFGF) mRNA‐expressing neurons was studied throughout the adult mouse central nervous system (CNS) with in situ hybridization histochemistry using a radiolabelled synthetic oligodeoxynucleotide probe complementary to the mRNA of human aFGF. We report here a widespread distribution of aFGF mRNA in several defined functional systems of the adult mouse brain, whereby the highest levels of aFGF mRNA were found in large somatomotor neurons in the nuclei of the oculomotor, trochlear, abducens, and hypoglossal nerves; in the motoneurons of the ventral spinal cord and the special visceromotor neurons in the motor nucleus of the trigeminal nerve; and in the facial and ambigaus nuclei. Labelled perikarya were also detected in all central structures of the auditory pathway including the level of the inferior colliculus, i.e., the lateral and medial superior nuclei; the trapezoid, cochlear, and lateral lemniscal nuclei; and parts of the anterior colliculus. Furthermore, many aFGF‐positive cell bodies were found in the vestibular system and other structures projecting to the cerebellum, in the deep cerebellar nuclei, in somatosensory structures of the medulla (i.e., in the gracile, cuneate, and external cuneate nuclei), as well as in the spinal nucleus of the trigeminal nerve. The findings that aFGF mRNA is expressed in all components of several well‐defined systems (i.e., in sensory structures) as Well as in central neurons that process sensory information and, finally, in some efferent projections point towards a concept of aFGF expression primarily within certain neuronal circuitries. © 1995 Wiley‐Liss, Inc.
Histological identification of premotor neurons for horizontal saccades in monkey and man by parvalbumin immunostaining
Authors: Horn Anja K. E. , Büttner‐Ennever Jean A. , Suzuki Yasuo , Henn Volker 
Published: January 2005

AbstractThe premotor excitatory and inhibitory burst neurons are essential for horizontal saccades. In the monkey, excitatory burst neurons lie in the ipsilateral paramedian pontine reticular formation, and the inhibitory burst neurons lie more caudally in the contralateral nucleus paragigantocellularis dorsalis. For a neuropathological analysis of degenerative changes in saccadic disorders of patients, the histological identification of the burst neuron areas in man is important. Here, we show that this is possible with parvalbumin immunostaining as a histological marker. First, in monkeys, the premotor burst neurons were backlabeled by injections of wheat germ agglutinin‐horseradish peroxidase or cholera toxin subunit B into the abducens nucleus or tetanus toxin fragment C into the lateral rectus muscle and shown by double labeling to contain parvalbumin. Then, human brainstein sections were immunoreacted for parvalbumin, and, by comparing the resulting staining pattern to that in the monkey, the homologous burst neuron areas were defined in man. In the monkey, excitatory burst neurons were confined to the nucleus reticularis pontis caudalis and did not extend farther rostrally into the nucleus reticularis pontis oralis. All retrogradely labeled cells in both burst neuron areas were parvalbumir. positive, and approximately 70% of the parvalbumin‐positive cells were retrogradely labeled. Both burst neuron areas were highlighted by their parvalbumin taining pattern and could be outlined in man as well. The putative excitatory burst neuron area in man is in the medial part of the nucleus reticularis pontis caudalis (extending 2.5 mm mediolaterally), immediately rostral (250 μm) to the omnipause neurons and extending 2.2 mm rostrally, and the putative inhibitory burst neuron area lies in the medial part of the paragigantocellular nucleus caudal to the abducqns nucleus, extending 1.8 mm caudally. The location of the burst neuron areas, including the burst neurons themselves, via parvalbuinin immunostaining will help in the analysis of clinical cases with slow saccades. © 1995 Wiley‐Liss, Inc.
Central nervous system neurons infected by pseudorabies virus injected into the rat urinary bladder following unilateral transection of the pelvic nerve
Authors: Nadelhaft Irving , Vera Pedro L. 
Published: January 2005

AbstractFollowing the transection of one pelvic nerve and both hypogastric nerves, the urinary bladder of male Sprague‐Dawley rats was injected with pseudorabies virus (PRV; Bartha strain). The central stump of the transected pelvic nerve was labelled with fast blue (FB), and rats were maintained for 2, 2. 5, and 3 days following viral infection. Tissue was processed with antisera against PRV and choline acetyltransferase (CAT). In the L6‐S1 spinal cord, neurons in the ipsilateral intermediolateral area (IML) were labelled after 2 days. After 2. 5 days, labelled neurons were also found in the dorsal gray commissure (DGC), the ipsilateral superficial dorsal horn, and the contralateral IML area. After 3 days, many labelled neurons appeared in the superficiai dorsal horns and, bilaterally, in the L6‐S1 dorsal root ganglia. In both IMLs, two groups of PRV‐labelled neurons were found: (1) CAT‐positive preganglionic cells and (2) smaller, CAT‐negative cells located slightly dorsal to the preganglionic neurons. No other doubly stained neurons were found in the spinal cord. Contralateral DRG neurons stained for either PRV or FB or both. Ipsilateral DRG neurons stained only for PRV. PRV‐immunoreactive (IR) neurons appeared in the brainstem only after 3 days. These were located primarily in the pontine micturition centers (equal numbers), the ventral locus coeruleus, and the raphe and lateral reticular areas. © 1995 Wiley‐Liss, Inc.
Effect of sensory deafferentation on immunoreactivity of GABAergic cells and on GABA receptors in the adult cat visual cortex
Authors: Rosier A. M. , Arckens L. , Demeulemeester H. , Orban G. A. , Eysel U. T. , Wu Y.‐J. , Vandesande F. 
Published: January 2005

AbstractTo investigate the effects of sensory deafferentation on the cortical GABAergic circuitry in adult cats, glutamic acid decarboxylase (GAD) and gamma‐aminobutyric acid (GABA) immunoreactivity and GABA receptor binding were studied in the visual cortex of normal cats and compared with cats that had received restricted binocular central lesions of the retina and had survived for 2 weeks postlesion in a normal visual environment.In the visual cortex of lesioned cats, two changes were observed in the number of GAD‐immunoreactive elements in the regions affected by the retinal lesions: the number of GAD‐positive puncta decreased, whereas that of GAD‐immunoreactive somata increased. In contrast, no detectable changes were measured in the number of GABA‐immunopositive somata or puncta. At the receptor level, we observed no differences in either the laminar distribution or the affinity of cortical GABAA and GABAB receptors labeled with [3H]‐muscimol and [3H]‐baclofen, respectively, in the lesioned versus normal cats.We present the hypothesis that sensory deafferentation in these adult cats (1) leads to a reduction of cortical GABAergic inhibition in the deafferented region, and (2) that this decreased inhibition may permit changes in efficiency of synapses and (3) that these changes may represent a first stage of events underlying the retinotopic reorganization preceeding the structural changes. © 1995 Wiley‐Liss, Inc.
Human cingulate cortex: Surface features, flat maps, and cytoarchitecture
Authors: Vogt Brent A. , Nimchinsky Esther A. , Vogt Leslie J. , Hof Patrick R. 
Published: January 2005

AbstractThe surface morphology land cytoarchitecture of human cingulate cortex was evaluated in the brains of 27 neurologically intact individuals. Variations in surface features included a single cingulate sulcus (CS) with or without segmentation or double parallel sulci with or without segmentation. The single CS was deeper (9.7 ± 0.81 mm) than in cases with double parallel sulci (7.5 ± 0.48 mm). There were dimples parallel to the CS in anterior cingulate cortex (ACC) and anastomoses between the CS and the superior CS. Flat maps of the medial cortical surface were made in a two‐stage reconstruction process and used to plot areas. The ACC is agranular and has a prominent layer V. Areas 33 and 25 have poor laminar differentiation, and there are three parts of area 24: area 24a adjacent to area 33 and partially within the callosal sulcus has homogeneous layers II and III, area 24b on the gyral surface has the most prominent layer Va of any cingulate area and distinct layers IIIa‐b and IIIc, and area 24c in the ventral bank of the CS has thin layers II–III and no differentiation of layer V. There are four caudal divisions of area 24. Areas 24a′ and 24b′ have a thinner layer Va and layer III is thicker and less dense than in areas 24a and 24b. Area 24c′ is caudal to area 24c and has densely packed, large pyramids throughout layer V. Area 24c'g is caudal to area 24c′ and has the largest layer Vb pyramidal neurons in cingulate cortex. Area 32 is a cingulofrontal transition cortex with large layer IIIc pyramidal neurons and a dysgranular layer IV. Area 32′ is caudal to area 32 and has an indistinct layer IV, larger layer IIIc pyramids, and fewer neurons in layer Va. Posterior cingulate cortex has medial and lateral parts of area 29, a dysgranular area 30, and three divisions of area 23: area 23a has a thin layer IIIc and moderate‐sized pyramids in layer Va, area 23b has large and prominent pyramids in layers IIIc and Va, and area 23c has the thinnest layers V and VI in cingulate cortex. Area 31 is the cinguloparietal transition area in the parasplenial lobules and has very large layer IIIc pyramids. Finally, variations in architecture between cases were assessed in neuron perikarya counts in area 23a. There was an age‐related decrease in neuron density in layer IV (r = −0.63; ages 45–102), but not in other layers. These observations provide structural underpinnings for interpreting functional imaging studies of the human medial surface. © 1995 Wiley‐Liss, Inc.
Development of the chiasm of a marsupial, the quokka wallaby
Authors: Harman Alison M. , Jeffery Glen 
Published: January 2005

AbstractWe have previously shown that the mature optic chiasm of a marsupial is divided morphologically into three regions, two lateral regions in which ipsilaterally projecting axons are confined and a central region containing only contralaterally projecting axons. By contrast, in the chiasms of eutherian (placental) mammals studied to date, there is no tripartite configuration. Ipsilaterally and contralaterally projecting axons from each eye are mixed in the caudal nerve and in each hemichiasm and encounter axons from the opposite eye near the midline of the chiasm. Here, we show that, unlike eutherians, marsupials have astrocytic processes in high concentrations in lateral regions of the nerve and rostral chiasm. Early in development, during the period when optic axons are growing through the chiasm, many intrachiasmatic cells are seen with densities five to eight times higher in lateral than in central chiasmatic regions. Such cells continue to be added to all chiasmatic regions; later in development, considerably more are added centrally, as the chiasm increases in volume. In the mature chiasm, cell densities are similar in all regions. By contrast to the marsupial, cell addition in the chiasm of a placental mammal, the ferret, is almost entirely restricted to later developmental stages, after axons have grown through the chiasm, and there are no obvious spatial variations in the distribution of cells during the period examined. During development, similar to the adult marsupial, ipsilaterally projecting axons do not approach the chiasmatic midline but remain confined laterally. We propose that the cells generated early and seen in high densities in the lateral chiasmatic regions of the marsupial may play a role in guiding retinal axons through this region of pathway selection. These data suggest that there is not a common pattern of developmental mechanisms that control the path of axons through the chiasm of different mammals. © 1995 Wiley‐Liss, Inc.
Nerve growth factor prevents apoptotic cell death in injured central cholinergic neurons
Authors: Wilcox Barbara J. , Applegate Michael D. , Portera‐Cailliau Carlos , Koliatsos Vassilis E. 
Published: January 2005

AbstractExperimental lesions have been widely used to induce neuronal degeneration and to test the ability of trophic molecules to prevent lesion‐induced alterations, but these studies have not demonstrated unequivocally that afflicted neurons die as a result of these manipulations. The documentation of neuronal death in the above‐described models and the time when it occurs after injury are crucial for the interpretation of trophic effects. In the present study, we combined multiple approaches to investigate the nature of retrograde neuronal changes in holinargic neurons of the medial septal nucleus (MSN) after complete, unilateral transection of the fimbria‐fornix (F‐F). Projection neurons of the MSN were prelabeled with the fluorescent tracer Fluoro‐gold (FG) 1 week prior to lesion. By counting both FG‐labeled and choline acetyltransferase (ChAT)‐immunoreactive neurons in the MSN at multiple time points postaxotomy, we differentiated the phenotypic response to injury from the degenerative process and established a critical time between the third and fourth weeks postaxotomy, during which ∼ 50% of fluorescent perikarya disappear. Working in the previous time window, we identified dying cells by electron microscopy (EM) and terminal transferase‐mediated (TdT) deoxyuridine triphosphate (d‐UTP)‐biotin nick end labeling (TUNEL) and showed that MSN neurons die via apoptosis, beginning at 16 days postaxotomy. An additional group of animals was allowed to survive for 1 month (i.e., 10 days after cell death has been completed); during this period, animals were treated with intraventricular nerve growth factor (NGF). Quantitative analysis of surviving cholinergic perikarya showed that NGF prevented retrograde degeneration of the majority of neurons. In concert, the results of the present study establish that NGF does not merely protect the phenotype but also prevents cell death in lesioned central cholinergic neurons. © 1995 Wiley‐Liss, Inc.
Development of catecholamine systems in the central nervous system of the newt Pleurodeles waltlii as revealed by tyrosine hydroxylase immunohistochemistry
Authors: González Agustín , Marín Oscar , Smeets Wilhelmus J. A. J. 
Published: January 2005

AbstractThe aim of the present study was to extend our knowledge of the development of catecholamine (CA) systems in the class of amphibians to the order of urodeles. In contrast to previous studies of urodeles, the present study with antisera against tyrosine hydroxylase (TH) and dopamine revealed that CA systems are already present at early embryonic stages of the newt, Pleurodeles waltlii. Although the development from fertilized egg to juvenile in the urodele Pleurodeles lasts twice as long as that in the anuran, Xenopus laevis, and shows less dramatic changes in external morphology, the spatiotemporal sequence of appearance of TH‐immunoreactive cell groups is rather similar. An early appearance of TH‐immunoreactive cell bodies occurs in the olfactory bulb, the posterior tubercle, the accompanying cell group of the hypothalamic periventricular organ, the suprachiasmatic nucleus, the locus codruleus, an area immediately ventral to the central canal of the spinal cord, and in the retina.The presence of CA systems at early embryonic stages of both anurans and urodeles suggests that these systems are already of functional significance early in development. The maturation of CA neuronal structures in the olfactory and retinal circuitries, which takes place during development earlier in amphibians than in mammals, supports that notion. © 1995 Wiley‐Liss, Inc.
Dendritic morphology of CA1 pyramidal neurones from the rat hippocampus: I. Branching patterns
Authors: Bannister N. J. , Larkman A. U. 
Published: January 2005

AbstractThe aim of this study was to provide quantitative descriptions of the dendritic branching patterns of pyramidal neurones in the CA1 region of the rat hippocampus. Thirteen adult cells were filled with biocytin and reconstructed by using the light microscope.The number of basal trees arising from the soma of each cell ranged from two to eight. There was wide variation in the number of terminal segments per tree. Six cells had single apical trunks, and seven had trunks that bifurcated in stratum radiatum. The number of apical oblique trees ranged from nine to 30, with each tree usually showing a lower degree of branching than basal trees. Basal and oblique trees had similar branching patterns, with the majority of branch points occurring close to the origin of the tree. Both basal and oblique terminal segments were generally much longer than intermediate segments and constituted up to 90% of the combined dendritic length of the tree. The branching pattern of the apical tuft was different, with many relatively long intermediate segments; terminal segments contributed only some 66% of the combined dendritic length of these trees. The mean total combined dendritic length for six adult cells reconstructed and measured completely was 11,900 ± 1,000 μm (standard deviation).The relative proportions of the different parts of the dendritic system, although not the total dendritic length, were correlated with the location of the soma relative, to the cell body layer. Cells with somata close to the stratum pyramidale/stratum radiatum border had more dendrites terminating in stratum radiatum and fewer in stratum oriens than cells with somata further from it. © 1995 Wiley‐Liss, Inc.
NGF mRNA is expressed by GABAergic but not cholinergic neurons in rat basal forebrain
Authors: Lauterborn Julie C. , Bizon Jennifer L. , Tran Tien M. D. , Gall Christine M. 
Published: January 2005

AbstractNerve growth factor (NGF) supports the survival and biosynthetic activities of basal forebrain cholinergic neurons and is expressed by neurons within lateral aspects of this system including the horizontal limb of the diagonal bands and magnocellular preoptic areas. In the present study, colormetric and isotopic in situ hybridization techniques were combined to identify the neurotransmitter phenotype of the NGF‐producing cells in these two areas. Adult rat forebrain tissue was processed for the colocalization of mRNA for NGF with mRNA for either choline acetyltransferase, a cholinergic cell marker, or glutamic acid decarboxylase, a GABAergic cell marker. In both regions, many neurons were single‐labeled for choline acetyltransferase mRNA, but cells containing both choline acetyltransferase and NGF mRNA were not detected. In these fields, virtually all NGF mRNA‐positive neurons contained glutamic acid decarboxylase mRNA. The double‐labeled cells comprised a subpopulation of GABAergic neurons; numerous cells labeled with glutamic acid decarboxylase cRNA alone were codistributed with the double‐labeled neurons. These data demonstrate that in basal forebrain GABAergic neurons are the principal source of locally produced NGF. © 1995 Wiley‐Liss, Inc.