bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distribution of nitric oxide synthase‐immunoreactive interneurons in the spinal trigeminal nucleus
Authors: Dohrn C. S. , Mullett M. A. , Price R. H. , Beitz A. J. 
Published: January 2005

AbstractThe spinal trigeminal nucleus is involved in the transmission of orofacial sensory information. Neither the distribution of the neuromessenger, nitric oxide, within the trigeminal system nor the possible relationship of this simple gas with trigeminothalamic neurons has been carefully studied. Using immunocytochemical (against nitric oxide synthase) and histochemical (NADPH‐diaphorase staining) techniques, we have found that nitric oxide neurons and processes are more prominent in the nucleus caudalis and the dorsomedial aspect of the nucleus oralis than in other spinal trigeminal regions. To study the relationship of nitric oxide to trigeminothalamic neurons and intertrigeminal interneurons of the spinal trigeminal nucleus, spinal trigeminal neurons were retrogradely labeled with fluorogold by thalamic injections or by injections into the junction of the nucleus interpolaris and nucleus caudalis. Medullary sections were subsequently processed with NADPH‐diaphorase histochemistry. None of the diaphorase‐stained neurons in the spinal trigeminal nucleus was found to contain fluorogold; however, some diaphorase‐stained processes were found in close proximity to trigeminothalamic neurons. Following spinal trigeminal nucleus injections, many diaphorasestained neurons were found to contain fluorogold, especially in the nucleus caudalis, suggesting that nitric oxide‐containing neurons in the spinal trigeminal nucleus are intertrigeminal interneurons. Collectively, these data indicate that nitric oxide is most prominent in interneurons located in nucleus caudalis and that these interneurons give rise to processes that appose trigeminothalamic neurons, raising the possibility that they may indirectly influence orofacial nociceptive processing at the level of the spinal trigeminal nucleus via nitric oxide production. © 1994 Wiley‐Liss, Inc.
Effects of vagal afferent nerve stimulation on noxious heat‐evoked Fos‐like immunoreactivity in the rat lumbar spinal cord
Authors: Evans Angela R. , Jones Sharon L. , Blair Robert W. 
Published: January 2005

AbstractElectrophysiological and behavioral studies have described modulation of nociception by vagal afferent fibers. The objectives of this study were to (1) use Fos‐like immunoreactivity as a marker for neuronal activity to examine populations of neurons in the spinal cord that are activated by a noxious heat stimulus, (2) determine whether heat‐evoked Fos‐like immunoreactivity can be modulated by vagal afferent stimulation, and (3) determine whether vagallymediated effects on heat‐evoked Fos‐like immunoreactivity can be blocked by intrathecally administered serotoninergic receptor and α‐adrenergic receptor antagonists.Neurons demonstratiring Fos‐like immunoreactivity were located in the ipsilateral superficial and deep dorsal horn laminae extending from the caudal L3 through the rostral L6 region of the spinal cord. Stimulation of the right cervical vagus nerve attenuated significantly (42%) heat‐evoked Fos‐like immunoreactivity in the superficial laminae. The reduction in Fos‐like immunoreactivity by vagal stimulation was abolished by intrathecal administration of methysergide, a nonselective serotoninergic receptor antagonist, but not by phentolamine, a nonselective α‐adrenoceptdr antagonist. These results suggest that vagal afferent modulation of spinal nociceptive transmission is mediated, at least in part, by serotonin receptors. © 1994 Wiley‐Liss, Inc.
Compartmentation of NADPH‐diaphorase activity in the mouse cerebellar cortex
Authors: Hawkes Richard , Turner Ray W. 
Published: January 2005

AbstractThe mammalian cerebellum is built around an array of parasagittal bands of Purkinje cells that can be demonstrated by immunocytochemical staining for the differentiation antigen zebrin II. Climbing and Mossy fiber afferents also terminate in bands, and the afferent terminal fields and the Purkinje cell bands are aligned. The convergence of mossy and climbing fiber pathways onto the Purkinje cells, which are the sole output of the cerebellar cortex, is a characteristic feature of cerebellar circuitry. Previous studies showed that when both afferent pathways are activated synchronously there develops a long‐term depression of synaptic efficacy at the parallel fiber‐Purkinje cell synapse. Two second messenger pathways mediate long‐term depression: one involves diacylglyceroland protein kinase C, and the other involves nitric oxide that is generated by a nitric oxide synthase. We have studied the distribution of nitric oxide synthase in the adult Mouse cerebellum by using nicatinamide adenine dinucleotide phosphate (NADPH)‐diaphorase histochemistry. NADPH‐diaphorase activity is found mainly in the granule and basket cells. Within the granular layer NADPH‐diaphorase activity is expressed nonuniformly patches of granule cells and synaptic glomeruli. The patches are yseen in all lobules, are reproducible from individual to individual, and are topographically ordered with respect to the Purkinje cell compartments as revealed by using anti‐zebrin II immunocytochemistry. These data imply that nitric oxide‐dependent, long‐term depression may only involve a subset of mossy fiber/granule cell projections, and that one role for nitric oxide may be to refine cerebellar receptive fields. © 1994 Wiley‐Liss, Inc.
Development of the retinofugal projections in the embryonic and larval zebrafish (Brachydanio rerio)
Authors: Burrill John D. , Easter Stephen S. 
Published: January 2005

AbstractStudies of the projection from the vertebrate retina have contributed significantly to current concepts of neural development. The zebrafish has recently become a favored system for the study of development in general and neural development in particular. Although the development of both the optic nerve and the retinotectal projection of the zebrafish has been described, the retinofugal projection in its entirety has not. This paper describes it and also addresses the issue of projectional exuberance: i. e., transient projections to targets that are not innervated in the adult.The retinofugal projection of embryonic and larval zebrafish (32 hours to 7 days post‐fertilization) was labeled by intraocular injection of DiI (1,1′‐dioctadecyl‐3,3,3′,3′, tetramethylindocarbocyanine perchlorate) and then studied in wholemounts and sections.The first optic axons crossed the chiasm at 32 hours post‐fertilization and projected in a straight line to reach the tectum at about 44 hours. At 48 hours, a few optic axons deviated along either the tract of the posterior commissure or the tract of the postoptic commissure. By 72 hours (about the time of hatching) optic axons arborized in ten distinct regions, termed arborization fields. At 6–7 days post‐fertilization, the same ten arborization fields (nine contralateral, one bilater) were evident. Most of the arborization fields were located in the superficial neuropil and were not associated with morphologically identifiable clusters of somata. On the basis of various landmarks, the ten arborization fields are identified as precursors of retinorecipient nuclei previously described in other adult cypriniform fishes.The development was characterized by the nearly complete absence of any transient projections. Thus, the idea that axonal outgrowth is initially exuberant and trimmed back later is not supported by these results. © 1994 Wiley‐Liss, Inc.
Distribution of motoneurons supplying dorsal and ventral suboccipital muscles in the feline neck
Authors: Kitamura S. , Richmond F. J. R. 
Published: January 2005

AbstractA combination of retrograde tracers was used to compare the relative distributions of motoneurons supplying the ventral and lateral suboccipital muscles, rectus capitis anterior (RCA), and rectus capitis lateralis (RCL), with those supplying dorsal muscles, including rectus capitis posterior muscles (RCP), complexus (CM), and the medial head of obliquus capitis superior (OCS). Three of the tracers, horseradish peroxidase, fluororuby, and fluoresceinconjugated dextran, were applied to cut nerve ends. Fast blue was applied by intramuscular injection, and fluorogold was delivered both by injection and by cut nerve exposure. Motoneurons supplying RCA and RCL were clustered on the medial wall of the ventral horn in a restricted region defined previously as the commissural nucleus. Labelled cells supplying RCL were confined to the C1 segment, but those supplying RCA were distributed from C1 to rostral C4. Motoneurons supplying RCA tended to lie more dorsomedially than those supplying RCL, but there was substantial overlap between the two populations. Motoneurons supplying dorsal muscles had a separate, more ventral distribution. RCP motoneurons were located primarily in the ventromedial nucleus, but a small proportion of cells was found in the white matter of the ventral funiculus or the gray matter surrounding the central canal. Motoneurons supplying CM and OCS were located dorsomedially to the RCP cell population. These results suggest that neck motoneurons are arranged according to a “musculotopic” pattern in which dorsal muscles have the most ventral locations, and progressively more lateral and then ventral muscles are layered dorsomedially along the medial wall of the ventral horn. © 1994 Wiley‐Liss, Inc.
Differential expression of five N‐methyl‐D‐aspartate receptor subunit mRNAs in the cerebellum of developing and adult rats
Authors: Akazawa Chihiro , Shigemoto Ryuichi , Bessho Yasumasa , Nakanishi Shigetada , Mizuno Noboru 
Published: January 2005

AbstractFive N‐methyl‐D‐aspartate (NMDA) receptor subunits have been identified thus far: NR1, NR2A, NR2B, NR2C, and NR2D. Here, we have analyzed the expression patterns of mRNAs for the NMDA receptor subunits in the developing and adult rats by in situ hybridization. The developmental changes of the expression patterns were most salient in the cerebellum.In the external granular layer, hybridization signals of mRNAs, for NR1, NR2A, NR2B, and NR2C appeared by postnatal day 3, but no NR2D mRNA was expressed at any developmental stage examined. The NR1 mRNA was expressed in all cerebellar neurons at all developmental stages examined. The signals for the NR2A mRNA appeared in Purkinje cells and granule cells during the second postnatal week. The signals for the NR2B mRNA in granule cells were seen transiently during the first 2 weeks after birth. The signals for NR2C mRNA appeared in granule cells and glial cells during the second postnatal week. The signals for NR2D mRNA appeared transiently in Purkinje cells during the first 8 postnatal days; in adult rats, these were seen in stellate and Golgi cells. In the cerebellar nuclei, mRNAs for NR1, NR2A, NR2B, and NR2D were more or less expressed on postnatal day 0, while expression signals for the NR2C mRNA were first detected in postnatal day 14. Thus, the most conspicuous changes of expression patterns were observed in the cerebellar cortex during the first 2 weeks after birth, when development and maturation of the cerebellum proceed most rapidly. © 1994 Wiley‐Liss, Inc.
Cloning and in situ hybridization analysis of estrogen receptor, progesterone and androgen receptor expression in the brain of whiptail lizards (Cnemidophorus uniparens and C. inornatus)
Authors: Young Larry J. , Lopreato Gregory F. , Horan Karen , Crews David 
Published: January 2005

AbstractGonadal steroid hormones act upon specific areas of the vertebrate brain to affect the reproductive physiology and behavior of the animal. Steroid receptors are members of a superfamily of ligand‐dependent transcription factors that mediate the effects of steroid hormones by modulating gene expression in the cells containing the receptors. The neuroanatomical distributions of steroid receptor‐containihg cells have been described for several species by using steroid autoradiography, immunocytochemistry, and more recently in situ hybridization. We have used the polymerase chain reaction to amplify and clone fragments of the estrogen receptor, progesterone receptor, and androgen receptor of whiptail lizards (genus Cnemidophorus). These clones were used to produce probes for use in in situ hybridization assays and to map the neuroanatomical distribution of all three sex steroid hormone receptors in the forebrains of unisexual (C. uniparens) and sexual (C. inornatus) species of whiptail lizards. The distribution of receptor‐expressing cells reported here is in general agreement with previous reports in other species with receptor‐containing cells concentrated in septal, amygdaloid, cortical, preoptic, and hypothalamic nuclei. © 1994 Wiley‐Liss, Inc.
Response properties of nociceptive and low‐threshold neurons in rat trigeminal pars caudalis
Authors: McHaffie John G. , Larson Michelle A. , Stein Barry E. 
Published: January 2005

AbstractThere is little doubt that trigeminal nociceptive neurons play a critical role in signaling the presence of harmful, or potentially harmful, orofacial stimuli. Unfortunately, there is only a limited understanding of how these neurons code such stimuli and whether this code is maintained in those structures responsible for generating overt reactions. The present series of experiments were designed to quantitatively document the response properties of nociceptive neurons in the rat trigeminal pars caudalis using the same electrical and innocuous and/or noxious mechanical and thermal stimuli employed in the characterization of nociceptive neurons with orofacial receptive fields in the rat superior colliculus. Neurons were classified as either low‐threshold mechanoreceptive, wide‐dynamic‐range, or nociceptive‐specific (type I, II) depending on their responsiveness to these stimuli. Nociceptive pars caudalis neurons (92/135, 68%) had receptive field organizations and input fibers (as indicated by latencies to electrical stimuli) quite different from those of low‐threshold neurons (43/135, 32%). Nociceptive stimulus‐response relationships for the population of wide‐dynamic‐range and nociceptive‐specific type I neurons to contact heat stimuli were positively accelerating power functions with exponents of 3.9 and 4.4, respectively. This contrasted sharply with the low‐threshold component of wide‐dynamic‐range neurons which was a negatively accelerating power function with an exponent of 0.7. All categories of nociceptive neuron also responded vigorously to cold stimuli. The thresholds of both hot and cold stimuli were often below psychophysical estimates of thermal pain, suggesting that “nociceptive” neurons process far more information than that required, to signal potentially harmful stimuli. The fundamental similarities in nociceptive properties in pars caudalis and other structures of the central nervous system suggest that there is little transformation of the information encoded at successive levels of the neuraxis. This is consistent with the idea that the functional role of nociceptive neurons is refiected more in which circuits they are integrated and less in differences in their physiological properties. © 1994 Wiley‐Liss, Inc.
Octopamine‐like immunoreactivity in the brain and subesophageal ganglion of the honeybee
Authors: Kreissl Sabine , Eichmüller Stefan , Bicker Gerd , Rapus Jürgen , Eckert Manfred 
Published: January 2005

AbstractThe organization of putative octopaminergic pathways in the brain and subesophageal ganglion of the honeybee was investigated with a well‐defined polyclonal antiserum against octopamine. Five prominent groups of just over 100 immunoreactive (IR) somata were found in the cerebral ganglion: Neurosecretory cells in the pars intercerebralis innervating the corpora cardiaca via NCC I, one cluster mediodorsal to the antennal lobe, one scattered on both sides of the midline of the protocerebrum, one between the lateral protocerebral lobes and the dorsal lobes, and a single soma on either side of the central body. With the exception of the pedunculi and β‐lobes of the mushroom bodies, varicose immunoreactive fibers penetrate all parts of the cerebral ganglion. Strong labelling was found in the central complex and the protocerebral bridge. Fine networks of labelled processes invade the antennal lobes, the calyces and a small part of the α‐lobes of the mushroom bodies, the protocerebrum, and all three optic ganglia.In the subesophageal ganglion, one labelled cell body was found in the lateral soma layer of the mandibular segment. Each of the three neuromeres contains a group of six to ten somata in the ventral median parts. Most of the ventral median cells send their neurites dorsally through the midline tracts, whereas the neurites of a few cells follow the ventral cell body neurite tracts.Octopamine‐IR was demonstrated in all neuropils that contain pathways for proboscis extension learning in honeybees. Because octopaminergic mechanisms seem to be involved in the behavioral plasticity of the proboscis extension reflex, our study provides anatomical data on the neurochemical organization of an appetitive learning paradigm. © 1994 Wiley‐Liss, Inc.
Abdominal surgery induces Fos immunoreactivity in the rat brain
Authors: Bonaz Bruno , Plourde Victor , Taché Yvette 
Published: January 2005

AbstractPrevious neuropharmacological studies indicate that brain peptides are involved in mediating gastric stasis induced by abdominal surgery. Central pathways activated by abdominal surgery were investigated in the rat by using Fos protein as a marker of neuronal activation. Abdominal surgery (laparotomy alone or combined with cecal manipulation) was performed under brief enflurance anesthesia (7–8 minutes), and 1 hour later rats were killed and brains processed for Fos immunoreactivity. Double labeling with Fos and arginine vasopressin, oxytocin, or tyrosine hydroxylase antibodies was also performed. Abdominal surgery induced Fos staining in the nucleus tractus solitarii, paraventricular and supraoptic nuclei of the hypothalamus, locus coeruleus, and ventrolateral medulla. After abdominal surgery, 18–25% of vasopressin and 18–33% of oxytocin‐labeled cells were found to be Fos positive in the paraventricular nucleus and 15% of activated cells in the nucleus tractus solitarii were positive for tyrosine hydroxylase immunoreactivity. Enflurane alone induced c‐fos expression in the same brain area; however, the number of Fos‐positive cells and double‐labeled cells were decreased two‐to fivefold and three‐ to eightfold, respectively, compared with the abdominal surgery groups. These data show that abdominal surgery induced activation of specific hypothalamic, pontine, and medullary neurons. These findings may have implications for the understanding of central mechanisms involved in mediating gastric ileus following abdominal surgery. © 1994 Wiley‐Liss, Inc.
Morphological analysis of external urethral and external anal sphincter motoneurones of cat
Authors: Sasaki Mitsuyoshi 
Published: January 2005

AbstractA previous electrophysiological study suggested that there is a common correlation among axonal conduction velocity, input resistance, and size of motoneurones regardless of the muscle type innervated by a motoneurone and that the dendritic arborization is less developed in sphincter than in hindlimb motoneurones. To verify the previous suggestions, cell bodies, axons, and dendrites of external urethral sphincter (EUS) and external anal sphincter (EAS) motoneurones were studied after intracellular labelling with horseradish peroxidase in cats anaesthetised with pentobarbitone. All the cell bodies were located in Onuf's nucleus. The soma diameter (19.7–50.0 μm) was positively correlated with the axonal conduction velocity, and the plots of these two variables were extrapolations from similar plots obtained for hindlimb α‐motoneurones, supporting the suggestion of the preceding report. Half of motoneurones had recurrent axon collaterals, which terminated within Onuf's nucleus and the ventral border of lamina VIII. The diameter of the cell body with collaterals was significantly larger than that without collaterals. Dendrites extended in five directions: dorsal, medial, lateral, rostral, and caudal. Dorsally directed dendrites of both EUS and EAS motoneurones coursed in lamina VII toward the intermediolateral nucleus, and dendrites of EAS motoneurones further extended toward the intermediomedial nucleus. Long dendrites directed rostrally or caudally within Onuf's nucleus, more prominently in EUS motoneurones. EAS motoneurones had longer end branches and relatively larger number of end branches and summed length and surface area of a dendrite compared with EUS. Among relations, the dendritic surface area and the dendritic volume were tightly correlated with the diameter of the first‐order dendrite. The latter relation was almost identical between EUS, EAS, and hindlimb α‐ and γ‐motoneurones. The large values for the dendritic‐to‐soma surface area ratio (31 in EUS, 50 in EAS) indicated the well‐developed dendritic arborization comparable to hindlimb motoneurones. The ratio of sum Σ(daughter diameter)3/2 to the 3/2 power of the parent diameter was 0.99 in EUS and 1.08 in EAS motoneurones, indicating that the 3/2 power constraint at branching points is well satisfied, and Rall's equivalent‐cylinder model is applicable to sphincter motoneurones. © 1994 Wiley‐Liss, Inc.