bluuebunny/crossref_metadata_2025_split huggingface dataset:
Retrograde labeling of neurons in the spinal cord that project directly to the amygdala or the orbital cortex in the rat
Authors: Burstein Rami , Potrebic Sonja 
Published: January 2005

AbstractThe amygdala and orbital cotex are thought to play an important role in the regulation of autonomic functions, hormonal secretion, and behavioral expression in response to sensory stimulation. The responsiveness of neurons in these regions to stimulation of cutaneous and visceral organs indicates that sensory information reaches the amygdala and orbital cortex. In the past, a large number of studies have thoroughly documented multiple neural pathways by which sensory information can reach these regions via relay nuclei in the brainstem and diencephalon. Recent studies reported that the amygdala and orbital cortex also receive direct input from the spinal cord. The aim of this study was to determine the magnitude and the origin of these projections in the rat.Injections of the retrograde tracer Fluoro‐Gold (FG), restricted to the amygdala, labeled several hundred neurons bilaterally (60% contralateral) throughout the length of the spinal cord. More than 60% of labeled neurons were found in the lateral reticulated area of the deep dorsal horn and the gray matter surrounding the central canal. Many neurons were also found in the lateral spinal nucleus. Labeled neurons were concentrated in upper lumbar and upper cervical segments.Injections of Fluoro‐Gold that were centered in the orbital cortex labeled only a small number of neurons (73% contralateral) within the spinal cord. Most labeled neurons were found in the lateral reticulated area. Neurons located in the intermediate zone and the gray matter surrounding the central canal were found mainly in upper lumbar and upper cervical segments.These findings, together with the anterograde tracing observations, provide evidence for direct projections of spinal cord neurons to the amygdala and orbital cortex. Their laminar distribution in the spinal cord and the involvement of the amygdala and orbital cortex in limbic functions suggest that these pathways may play a role in neuronal circuits that enable somatosensory information, including pain, to affect autonomic, endocrine and behavioral functions. © 1993 Wiley‐Liss, Inc.
Fate of abdominal ventral unpaired median cells during metamorphosis of the hawkmoth, Manduca sexta
Authors: Pflüger H. J. , Witten J. L. , Levine Richard. B. 
Published: January 2005

AbstractEach of the unfused abdominal ganglia in the larval, pupal, and adult stages of the hawkmoth, Manduca sexta, has two large ventral median neurons with axons that bifurcate to innervate targets on both sides of the abdomen. Although the dendritic structures of the two neurons are similar, their axons branch to innervate distinct sets of target muscles. During metamorphosis both neurons undergo dendritic regression, followed by growth of new arborizations during adult development. The neurons must innervate different targets in the larva and adult, since many larval muscles degenerate and are replaced during metamorphosis. Both neurons were reactive with an antibody to the neuromodulatory compound, octopamine, in the larval and adult stages. Pairwise intracellular recordings in isolated nerve cords revealed spontaneous excitatory synaptic potentials that occurred in the ventral median neurons of each ganglion in an anterior‐to‐posterior sequence. The synaptic potentials were eliminated when the interganglionic connective was interrupted posterior to the subesophageal ganglion. The ventral median neurons were also excited by tactile stimulation of the body surface in larvae, pupae and adults. © 1993 Wiley‐Liss, Inc.
Nitric oxide synthase‐like immunoreactivity in lumbar dorsal root ganglia and spinal cord of rat and monkey and effect of peripheral axotomy
Authors: Zhang Xu , Verge Valerie , Wiesenfeld‐Hallin Zsuzsanna , Ju Gong , Bredt David , Snyder Solomon H. , Hökfelt Tomas 
Published: January 2005

AbstractWith the immunofluorescence technique, nitric oxide synthase (NOS)‐like immunoreactivity (LI) was found in a few medium‐sized and small sensory neurons in lumbar (L) 4 and L5 dorsal root ganglia (DRG) of normal rat, and in most of these neurons, NOS‐LI coexisted with calcitonin gene‐related peptide and sometimes with substance P and galanin. NOS‐immunoreactive nerve fibers, terminals and small neurons were also located in the dorsal horn of the segments 4 and 5 of the rat lumbar spinal cord with the highest density in inner lamina II. Many NOS‐positive neurons and fibers were seen in the area around the central canal. A sparse network of NOS‐immunoreactive nerve fibers was found in the ventral horn. After unilateral sciatic nerve cut in the rat, the number of NOS‐positive neurons increased in the ipsilateral L4 and L5 DRGs, mainly in medium and small neurons, but also in some large neurons and very small neurons. NOS‐LI could now also be seen in the ipsilateral dorsal roots, and in an increased number of fibers and terminals in both outer and inner lamina II of the ipsilateral dorsal horn. The number of NOS‐immunoreactive neurons in lamina II of the ipsilateral dorsal horn was reduced. In the monkey L4 and L5 DRGs, many small neurons were NOS‐immunoreactive, but only a few weakly stained nerve fibers and terminals were found in laminae I‐IV of the dorsal horn at L4 and L5 lumbar levels. A few NOS‐positive neurons were present in lamina X. The number of NOS‐immunoreactive neurons was somewhat reduced in DRGs 14 days after peripheral axotomy, but no certain effect was seen in the dorsal horn. These results, together with earlier in situ hybridization studies, demonstrate that axotomy in rat induces a marked upregulation of NOS synthesis in primary sensory neurons, thus suggesting a role for NO in lesioned sensory neurons. In contrast, no such effect was recorded in monkey, perhaps indicating distinct species differences. © 1993 Wiley‐Liss, Inc.
Tanycytes in the sunfish brain: NADPH‐diaphorase histochemistry and regional distribution
Authors: Ma Pokay M. 
Published: January 2005

AbstractNADPH‐diaphorase histochemistry has been shown to be a useful method for identifying cells that synthesize and release nitric oxide, which is implicated in the modulation of a variety of neural functions, including synaptic transmission, cerebral blood flow, and excitotoxicity. In the sunfish brain, NADPH‐diaphorase histochemistry stains tanycytes specifically and almost exclusively, allowing for a thorough examination of the morphology and distribution of this type of cell. Tanycytes are nonciliated, process‐bearing ependymal and extraependymal cells that contact the ventricular surface via apical processes, and the pial surface via basal processes. Ependymal tanycytes are located at the ventricular surface, and project basal processes into the parenchyma of the brain. Extraependymal tanycytes are found away from the ventricular matrix. Some extraependymal tanycytes are small, bipolar, and tend to be associated with bundles of basal processes. Isolated extraependymal tanycytes are larger, darkly stained, and multipolar. Their basal processes terminate in specialized endfeet on blood vessels, neuronal somata, or the pial surface. Specialized types of tanycytes are found in the optic tectum, the epineurial septum between axonal bundles along the midline in the medulla, and in restricted regions on the pial surface in the medulla. The only NADPH‐diaphorase‐positive neurons are found in the commissural nucleus of area ventralis telencephali. Injection of horseradish peroxidase into the ventricles shows that tanycytes lining the third and fourth ventricles are capable of taking up the tracer and transporting it into their basal processes.Tanycytes are unevenly distributed in the brain. There is a rough rostrocaudal gradient of cell density: tanycytes are sparse in the telencephalon and dense in the isthmus and medulla, although cell density is low in the spinal cord. Not all ventricular linings contain tanycytes: cell density is low in the medial ventricle of the telencephalon and in the infundibular recess, and high along the fourth ventricle.The function of tanycytes in the sunfish is not known. The association of tanycytes with both the ventricles and blood vessels raises the possibility that they play some role in sampling the biochemical constituents of both compartments and communicating the information to neural elements. It is proposed that tanycytes react to the biochemical composition in the ventrile and plasma by increasing or decreasing nitric oxide synthesis and release, which in turn influence neuronal activity or cerebral blood flow. © 1993 Wiley‐Liss, Inc.
Neurophysin‐containing pathway from the paraventricular nucleus of the hypothalamus to a sexually dimorphic motor nucleus in lumbar spinal cord
Authors: Wagner Christine K. , Clemens Lynwood G. 
Published: January 2005

AbstractA model that has been widely used in the study of steroid sensitive neurons, the spinal nucleus of the bulbocavernosus (SNB) is a sexually dimorphic motor nucleus in the lower lumbar spinal cord that innervates the striated bulbocavernosus (BC) muscle. The BC is responsible for penile reflexes in the male rat, which are important in ensuring pregnancy in females. The characterization of afferents to the SNB aids in the understanding of the neural circuitry involved in reproductive behavior. We have recently identified the paraventricular nucleus (PVN) as a possible source of afferents to the SNB. Because the PVN is the major source of oxytocin/vasopressin within the central nervous system (CNS), the purpose of the present study was to examine and characterize a neurophysin (NP)‐containing pathway from the PVN to the SNB. The results demonstrate that neurons of the lateral parvicellular subnucleus of PVN, which project to levels of spinal cord containing SNB motoneurons, contain NP, the coproduct of oxytocin and vasopressin. NP‐containing fibers and putative terminals were found in the region of the SNB and appear to contact the soma and proximal dendrites of SNB motoneurons which were retrogradely identified as BC‐innervating. Electrolytic lesions, which destroy the lateral parvicellular subnucleus of PVN, abolish NP‐containing fibers in the region of the SNB, suggesting that the PVN is the source of these NP fibers. The results of this study indicate a NP‐containing projection from the hypothalamus directly to SNB motoneurons. It is suggested that this pathway may play a role in the integration of penile reflexes with other aspects of male copulatory behavior that are under hypothalamic control. © 1993 Wiley‐Liss, Inc.
NGF Augmentation rescues trigeminal ganglion and principalis neurons, but not brainstem or cortical whisker patterns, after infraorbital nerve injury at birth
Authors: Henderson Theodore A. , Rhoades Robert W. , Bennett‐Clarke Carol A. , Osborne Pat A. , Johnson Eugene M. , Jacquin Mark F. 
Published: January 2005

AbstractPrior studies indicate that neonatal nerve injury kills many trigeminal (V) first‐ and second‐order cells, and interrupts pattern formation in the brainstem and cerebral cortex. Yet it is not known whether effects upon cell survival and pattern formation are causally related. To determine whether axotomized V ganglion cells can be rescued by an exogenous trophic agent, rats received 5 mg/kg of nerve growth factor (NGF) prior to, and every day after, infraorbital nerve section on the day of birth until sacrifice on postnatal day (PND) 1, 3, 5, 7, or 14. Other animals received identical lesions without NGF. Ganglion cell numbers were significantly reduced by PNDl in pups not given NGF, while NGF‐treated rats displayed no significant cell loss through PND7. However, NGF did not permanently rescue V neurons because ganglion cell numbers were reliably reduced by PND14.Cell numbers in V nucleus principalis were reduced by PNDl in pups not given NGF, while NGF‐treated animals displayed no cell loss through PND14. NGF's rescue of second‐order cells is probably an indirect effect of NGF actions upon V ganglion cells because, in other newborns, NGF failed to maintain principalis cells after direct lesion of the left V ganglion.To determine whether preventing cell death permits whisker‐related pattern formation, other rats also received NGF prior to and after infraorbital nerve section at birth. After 3–14 days, patterns were assessed in the brainstem and cortex with cytochrome oxidase histochemistry and serotonin immunocytochemistry. Whisker‐related patterns failed to develop as in cases not given NGF.These data indicate that communication with the periphery is necessary for the maintenance of central whisker‐related patterns. They also suggest that V ganglion cells can be rescued, albeit temporarily, from rapid injury‐induced death by NGF, thereby delaying injury‐induced cell death in nucleus principalis. However, the mechanism(s) responsible for injury‐induced pattern alterations in the developing V system remains to be elucidated. © 1993 Wiley‐Liss, Inc.
Origins of cerebellar mossy and climbing fibers immunoreactive for corticotropin‐releasing factor in the rabbit
Authors: Errico P. , Barmack N. H. 
Published: January 2005

AbstractCorticotropin‐releasing factor (CRF) has been implicated by both anatomical and physiological techniques as a potential cerebellar transmitter or modulator. In the present experiment, with the aid of immunohistochemistry, we have described specific cerebellar afferent pathways in the rabbit in which CRF is located. CRF‐immunoreactive climbing fibers were present in the molecular layer throughout the cerebellum, but especially in lobules 8–9a. All inferior olivary neurons were CRF‐immunoreactive.In lobules 8–9a, CRF‐immunoreactive mossy fibers were organized in sagittal bands. The highest density of CRF‐immunoreactive mossy fiber terminals was observed in the granule cell layer of lobules 8–9a and the flocculus. No CRF‐immunoreactive perikarya were located in rabbit cerebellum. The brainstem origin of CRF‐immunoreactive mossy fiber terminals was suggested by numerous CRF‐immunoreactive perikarya located in the medial, lateral and descending vestibular nuclei, nucleus prepositus hypoglossi, nucleus x, paramedian reticular nucleus, gigantocellular reticular nucleus, lateral reticular nucleus, and raphe nuclei.Using double label experiments, we investigated the specific CRF afferent projection to the flocculus and posterior vermis. Horseradish peroxidase (HRP) injections into the posterior vermis double labeled CRF‐immunoreactive neurons in the caudal medial and descending vestibular nuclei and nucleus prepositus hypoglossi. HRP injections into the flocculus double labeled more CRF‐immunoreactive neurons in the nucleus prepositus hypoglossi than in the vestibular nuclei. HRP injections into either the posterior vermis or flocculus double labeled CRF‐immunoreactive neurons in the paramedian reticular nucleus, nucleus reticularis gigantocellularis, and raphe nuclei. These data suggest that CRF may play an important role in vestibularly related functions of the cerebellum. © 1993 Wiley‐Liss, Inc.
Parvalbumin‐containing neurons in the cerebral cortex of the lizard Podarcis hispanica: Morphology, ultrastructure, and coexistence with GABA, somatostatin, and neuropeptide Y
Authors: Martínez‐Guijarro F. J. , Soriano E. , Del Río J. A. , Blasco‐Ibáñez J. M. , López‐Garcia C. 
Published: January 2005

AbstractThe morphology, fine structure, and degree of colocalization with GABA, somatostatin, and neuropeptide Y of parvalbumin‐containing cells were studied with immunocytochemistry in the cerebral cortex of the lizard Podarcis hispanica. Parvalbumin‐containing cells make up a morphologically heterogeneous population of spine‐free neurons, displaying the morphological features of nonprincipal cells previously described in Golgi studies. Electron microscopically, parvalbumin‐immunoreactive cell bodies are similar in all cortical areas and layers. The perisomatic input is moderate in number, and boutons with either round clear vesicles or flattened vesicles were observed making asymmetric or symmetric synaptic contacts, respectively. Parvalbumin‐immunoreactive dendrites are smooth and almost completely covered with synaptic boutons of different types, most of which establish asymmetric contacts. Parvalbumin‐immunoreactive boutons are concentrated around cell bodies of principal cells. They are large, containing abundant mitochondria and small pleomorphic vesicles, and establishing symmetric synaptic contacts with somata, proximal dendritic shafts, and axon initial segments of principal cells. Colocalization studies revealed that all the parvalbumin‐containing cells are GABA‐immunoreactive, representing only a fraction of the GABA‐immunopositive cell population, and that parvalbumin‐ and peptide‐ (somatostatin and neuropeptide Y) containing cells show a negligible overlap.These results demonstrate that in the cerebral cortex of the lizard Podarcis hispanica, parvalbumin‐containing cells represent a subset of nonprincipal GABAergic neurons largely involved in perisomatic inhibition, which are different from the peptide‐containing cells, and suggest that they may include both axosomatic and axoaxonic cells. © 1993 Wiley‐Liss, Inc.
Immunocytochemical localization of neuropeptide FF (FMRF amide‐like peptide) in the hypothalamo‐neurohypophyseal system of Wistar and Brattleboro rats by light and electron microscopy
Authors: Boersma C. J. C. , Sonnemans M. A. F. , van Leeuwen F. W. 
Published: January 2005

AbstractNeuropeptide FF (F8Famide, FMRFamide‐like, or morphine modulating peptide) immunoreactivity was localized by light and electron microscopy in the hypothalamo‐neurohypophyseal system of Wistar and Brattleboro rats. In Wistar rats neuropeptide FF was present in part of the magnocellular neurones of the paraventricular and supraoptic nuclei in which it was coexpressed with vasopressin. Neuropeptide FF containing fibers were present in the paraventricular and the supraoptic nuclei, and in the central part of the neural lobe. At the electron microscopic level, neuropeptide FF containing nerve terminals in the neural lobe formed synaptoid contacts exclusively with pituicytes. No neuropeptide FF containing neurovascular contacts or contacts with other neuronal structures were observed.In contrast with Wistar rats, neuropeptide FF was almost completely absent in cell bodies of the paraventricular and supraoptic nuclei, and in fibres of the neural lobe in Brattleboro rats. Only a few solitary cells could be observed in these structures. The present results demonstrate that neuropeptide FF coexists with vasopressin within the hypothalamo‐neurohypophyseal system. As we did not observe neuropeptide FF containing neurovascular contacts, neuropeptide FF containing nerve terminals probably have a local function within the neural lobe. Neuropeptide FF may be involved in the modulation ofoxytocin and vasopressin release, with the pituicyte as an intermediate cell. © 1993 Wiley‐Liss, Inc.
Three‐dimensional analysis of the dendritic domains of on‐ and off‐cells in the rostral ventromedial medulla
Authors: Potrebic S. B. , Mason P. 
Published: January 2005

AbstractThe rostral ventromedial medulla contains two classes of physiologically defined neurons, on‐cells and off‐cells, that are implicated in nociceptive modulation. In a continuing effort to detail the neural circuitry that underlies the activity of these two distinct neuronal types, the three‐dimensional somatodendritic morphology of on‐ and off‐cells was studied in the cat and the rat.Following physiological characterization with intracellular recording, on‐ and off‐cells were injected with horseradish peroxidase and sectioned in the coronal plane. Their somatodendritic arborizations were reconstructed with the aid of a computerized three‐dimensional reconstruction program.There were no differences between on‐ and off‐cells in any somatodendritic feature analyzed. On‐ and off‐cells possess dendritic arbors that are elongated in the mediolateral axis relative to the dorsoventral and rostrocaudal axes. In the rat, the average dendritic extent was more than 1,400 μm mediolaterally but only about 800 μm in either the dorsoventral or rostrocaudal axis. All somatic and dendritic measures were greater for both cat cells than for any rat neuron. Dendrites and their tips were located predominantly in regions lateral to the soma. The center of total dendritic length was usally located within 150 μm of the soma, most frequently ventral and lateral to the soma.The present results demonstrate that the dendritic domains of neurons in the nuclei raphe magnus and reticularis paragigantocellularis pars alpha are not contained within cytoarchitechtonic boundaries. On‐ and off‐cell dendrites are interdigitated throughtout the mediolateral extent of the rostral ventromedial medulla. Since on‐ and off‐cell dendritic domains occupy a restricted rostrocaudal plane, afferents to the rostral ventromedial medulla that are confined to a single coronal plane and those that collateralize at several levels are likely to play different roles in the control of on‐and off‐cell activity. © 1993 Wiley‐Liss,Inc.
Prelunate, occipitotemporal, and parahippocampal projections to the basis pontis in rhesus monkey
Authors: Schmahmann Jeremy D. , Pandya Deepak N. 
Published: January 2005

AbstractWe used tritiated amino acids to study projections to the basilar pons from prestriate cortices in 18 rhesus monkeys to determine how connectional and functional heterogeneity of these regions are reflected in corticopontine circuitry. Fibers travelled with those from other parasensory associative cortices before terminating in the pontine nuclei. Prelunate projections were derived from area 19 (OA) at the medial convexity (including areas V3 and PO) and from the lateral convexity dorsal to the caudal tip of the Sylvian fissure (including areas DP and the dorsal part of area V4d). Pontine projections also arose from area 19 (OA), and areas TF, TL, and TH in the posterior aspect of the parahippocampal gyrus. No pontine projections arose from the prelunate convexity ventral to the caudal tip of the Sylvian fissure (ventral part of area V4d and area V4v), area TEO, the inferior temporal gyrus, or the lateral ventral temporal region. Terminations in the pons were distributed in the dorsolateral and lateral nuclei, and the lateral part of the peripeduncular nucleus. Medial convexity injections produced more extensive rostrocaudal pontine labeling, as well as terminations in the extreme dorsolateral nucleus and the nucleus reticularis tegmenti pontis. Dorsal prelunate injections had additional terminations in the ventral pontine nucleus. Posterior parahippocampal gyrus injections resulted in discrete label in the lateral and dorsolateral nuclei.Corticopontine projections destined for the cerebellum appear to be derived from extrastriate areas concerned mainly with visual spatial parameters, visual motion, and the peripheral field of vision, but not from areas subserving visual object identification and the central field of vision. Pontine afferents from the posterior parahippocampal gyrus may facilitate a cerebellar contribution to visual spatial memory, particularly when invested with motivational valence. © 1993 Wiley‐Liss,Inc.