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The Neuroscientist : a Review Journal... Oct 2009Neurons in sensory ganglia are surrounded by satellite glial cells (SGCs) that perform similar functions to the glia found in the CNS. When primary sensory neurons are... (Review)
Review
Neurons in sensory ganglia are surrounded by satellite glial cells (SGCs) that perform similar functions to the glia found in the CNS. When primary sensory neurons are injured, the surrounding SGCs undergo characteristic changes. There is good evidence that the SGCs are not just bystanders to the injury but play an active role in the initiation and maintenance of neuronal changes that underlie neuropathic pain. In this article the authors review the literature on the relationship between SGCs and nociception and present evidence that changes in SGC potassium ion buffering capacity and glutamate recycling can lead to neuropathic pain-like behavior in animal models. The role that SGCs play in the immune responses to injury is also considered. We propose the term gliopathic pain to describe those conditions in which central or peripheral glia are thought to be the principal generators of principal pain generators.
Topics: Adenosine Triphosphate; Animals; Cell Communication; Cell Proliferation; Ganglia, Sensory; Glutamic Acid; Humans; Peripheral Nervous System Diseases; Potassium; Satellite Cells, Perineuronal; Sensory Receptor Cells
PubMed: 19826169
DOI: 10.1177/1073858409336094 -
Singapore Medical Journal Dec 2017Hand tumours are frequently encountered in clinical practice. A list of differential diagnoses of the most common hand tumours based on anatomical location would be...
INTRODUCTION
Hand tumours are frequently encountered in clinical practice. A list of differential diagnoses of the most common hand tumours based on anatomical location would be helpful for clinicians. We aimed to determine the anatomical distribution of hand tumours seen at a hand surgery practice in Singapore.
METHODS
The medical records of 50 men and 65 women (mean age 41.7 [range 17-74] years) who underwent excision of hand tumours between 1 June 2010 and 31 December 2012 were reviewed. The histological diagnoses and anatomical locations of the tumours were analysed. The locations were divided into three main groups: (a) distal to the metacarpophalangeal joints (MCPJs); (b) between the MCPJs and carpometacarpal joints (CMCJs); and (c) between the CMCJs and the radiocarpal joint (RCJ).
RESULTS
Overall, the most common tumours excised from the hand were ganglions (n = 66/116, 56.9%) and giant cell tumours of the tendon sheath (GCTTSs; n = 11/116, 9.5%). However, distal to the MCPJs, GCTTSs (n = 11/39, 28.2%) were more common than ganglions (n = 7/39, 17.9%). Most of the ganglions (n = 59/66, 89.4%) arose from between the CMCJs and RCJ.
CONCLUSION
Most hand tumours were benign. Ganglions were the most common tumours between the CMCJs and RCJ, while GCTTSs were the most common tumours distal to the MCPJs.
Topics: Adolescent; Adult; Aged; Carpal Joints; Carpometacarpal Joints; Diagnosis, Differential; Female; Ganglion Cysts; Giant Cell Tumors; Hand; Humans; Incidence; Male; Metacarpophalangeal Joint; Middle Aged; Radius; Retrospective Studies; Singapore; Young Adult
PubMed: 27570868
DOI: 10.11622/smedj.2016147 -
Journal of Visualized Experiments : JoVE Apr 2016Somatosensory nerves transduce thermal, mechanical, chemical, and noxious stimuli caused by both endogenous and environmental agents. The cell bodies of these afferent...
Somatosensory nerves transduce thermal, mechanical, chemical, and noxious stimuli caused by both endogenous and environmental agents. The cell bodies of these afferent neurons are located within the sensory ganglia. Sensory ganglia innervate a specific organ or portion of the body. For instance, the dorsal root ganglia (DRG) are located in the vertebral column and extend processes throughout the body and limbs. The trigeminal ganglia are located in the skull and innervate the face, and upper airways. Vagal afferents of the nodose ganglia extend throughout the gut, heart, and lungs. The nodose neurons control a diverse array of functions such as: respiratory rate, airway irritation, and cough reflexes. Thus, to understand and manipulate their function, it is critical to identify and isolate airway specific neuronal sub-populations. In the mouse, the airways are exposed to a fluorescent tracer dye, Fast Blue, for retrograde tracing of airway-specific nodose neurons. The nodose ganglia are dissociated and fluorescence activated cell (FAC) sorting is used to collect dye positive cells. Next, high quality ribonucleic acid (RNA) is extracted from dye positive cells for next generation sequencing. Using this method airway specific neuronal gene expression is determined.
Topics: Animals; Ganglia, Spinal; High-Throughput Nucleotide Sequencing; Mice; Neurons, Afferent; Nodose Ganglion; Sensory Receptor Cells; Vagus Nerve
PubMed: 27168016
DOI: 10.3791/53917 -
Journal of Anatomy Nov 2021Based on a previous study by others reporting that PIP5Kγ (phosphatidylinositol 4-phosphate 5-kinase γ) and its product, phosphatidylinositol 4,5 bisphosphate (PIP ),...
Localization of PIP5Kγ selectively in proprioceptive peripheral fields and also in sensory ganglionic satellite cells as well as neuronal cell membranes and their central terminals.
Based on a previous study by others reporting that PIP5Kγ (phosphatidylinositol 4-phosphate 5-kinase γ) and its product, phosphatidylinositol 4,5 bisphosphate (PIP ), are involved in the regulation of nociception, the present immunohistochemical study examined the localization of PIP5Kγ-immunoreactivity in dorsal root ganglia (DRG) and their peripheral and central terminal fields. PIP5Kγ-immunoreactivity was localized for the first time in the muscle spindles, in which it was found in I-bands of polar regions of intrafusal muscle fibers and also in sensory nerve terminals abutting on equatorial regions of the muscle fibers. This finding indicates the involvement of PIP5Kγ in the proprioception and suggests somehow complicated mechanisms of its involvement because of its heterogeneous localization in intra-I-band structures. In DRG, on the other hand, PIP5Kγ-immunoreactivity was shown to be localized heterogeneously, but not evenly, over apposed plasma membranes of both neurons and ganglionic satellite cells in immune electron microscopy. In addition, no peripheral nerve terminals of DRG showing its distinct immunoreactivity were found in most peripheral fields of nociception and any other sensory perception except for the proprioception through muscle spindles. In contrast, numerous central terminals of DRG in the spinal posterior horn were immunoreactive for it. This finding leads us to consider the possibility that the regulation by PIP5Kγ of nociception is dominantly exerted in DRG and sensory neural tracts central, rather than peripheral, to DRG.
Topics: Cell Membrane; Ganglia, Spinal; Muscle Spindles; Proprioception; Sensory Receptor Cells
PubMed: 34151437
DOI: 10.1111/joa.13491 -
Stem Cell Research & Therapy Oct 2022In enteric neural stem cell (ENSC) therapy for enteric neuropathy, the gut is ostensibly accessible via laparotomy, laparoscopy or endoscopy, whereas its elongated...
BACKGROUND
In enteric neural stem cell (ENSC) therapy for enteric neuropathy, the gut is ostensibly accessible via laparotomy, laparoscopy or endoscopy, whereas its elongated configuration and multilayered structures substantially complicate the targeting of ENSC delivery. This study aimed to evaluate the feasibility of ENSC delivery via trans-anal rectal submucosal injection.
METHODS
ENSC transplantation was conducted in an immunologically compatible model of FVB/NCrl-Tg(Pgk1-EGFP)01Narl into FVB/N murine strain combination. Enteric neurospheres were mass-produced by the cultivation of dispersed enterocytes harvested from gestational day 14 FVB/NCrl-Tg(Pgk1-EGFP)01Narl murine fetuses. Dissociated neurosphere cells were injected into rectal submucosa of adult FVB/N mice after artificial prolapse of rectal mucosa. Ganglion reconstitution in recipients' colon was examined by immunohistochemcal and immunofluorescence staining.
RESULTS
Cell spreading and ganglion assembly in recipients' colorectum were examined one week after transplantation. Donor ENSCs migrated rostrally within the colonic wall to intermuscularly repopulate the neighboring colorectum and assemble myenteric ganglia. It contributed to a chimeric state of myenteric plexuses with donor-origin ganglia of 41.2-67.5%. Two months later, transplanted ENSCs had undergone long-distance caudorostral migration almost up to the cecum to reconstitute myenteric and submucosal ganglia along the entire length of the colon.
CONCLUSION
This proof-of-principle study provided a viable justification for minimally invasive rectal ENSC transplantation to create long-term and long-range reconstitution of enteric ganglia. It opens up the new approach to ENSC delivery in laboratory animals and casts light on the feasibility of replacing damaged or replenishing missing enteric neurons by trans-anal rectal ENSC transplantation.
Topics: Animals; Colon; Enteric Nervous System; Ganglia; Mice; Neural Stem Cells; Neurons
PubMed: 36210457
DOI: 10.1186/s13287-022-03187-2 -
Journal of Neurophysiology Nov 1999We have used multiple-labeling immunohistochemistry, intracellular dye-filling, and intracellular microelectrode recordings to characterize the morphological and... (Comparative Study)
Comparative Study
We have used multiple-labeling immunohistochemistry, intracellular dye-filling, and intracellular microelectrode recordings to characterize the morphological and electrical properties of sympathetic neurons in the superior cervical, thoracic, and celiac ganglia of mice. Neurochemical and morphological characteristics of neurons varied between ganglia. Thoracic sympathetic ganglia contained three main populations of neurons based on differential patterns of expression of immunoreactivity to tyrosine hydroxylase, neuropeptide Y (NPY) and vasoactive intestinal peptide (VIP). In the celiac ganglion, nearly all neurons contained immunoreactivity to both tyrosine hydroxylase and NPY. Both the overall size of the dendritic tree and the number of primary dendrites were greater in neurons from the thoracic and celiac ganglia compared with those from the superior cervical ganglion. The electrophysiological properties of sympathetic neurons depended more on their ganglion of origin rather than their probable targets. All neurons in the superior cervical ganglion had phasic firing properties and large afterhyperpolarizations (AHPs). In addition, 34% of these neurons displayed an afterdepolarization preceding the AHP. Superior cervical ganglion neurons had prominent I(M), I(A), and I(H) currents and a linear current-voltage relationship between -60 and -110 mV. Neurons from the thoracic ganglia had significantly smaller action potentials, AHPs, and apparent cell capacitance compared with superior cervical ganglion neurons, and only 18% showed an afterdepolarization. All neurons in superior cervical ganglia and most neurons in celiac ganglia received at least one strong preganglionic input. Nearly one-half the neurons in the celiac ganglion had tonic firing properties, and another 15% had firing properties intermediate between those of tonic and phasic neurons. Most celiac neurons showed significant inward rectification below -90 mV. They also expressed I(A), but with slower inactivation kinetics than that of superior cervical or thoracic neurons. Both phasic and tonic celiac ganglion neurons received synaptic inputs via the celiac nerves in addition to strong inputs via the splanchnic nerves. Multivariate statistical analysis revealed that the properties of the action potential, the AHP, and the apparent cell capacitance together were sufficient to correctly classify 80% of neurons according to their ganglion of origin. These results indicate that there is considerable heterogeneity in the morphological, neurochemical, and electrical properties of sympathetic neurons in mice. Although the morphological and neurochemical characteristics of the neurons are likely to be related to their peripheral projections, the expression of particular electrophysiological traits seems to be more closely related to the ganglia within which the neurons occur.
Topics: Action Potentials; Animals; Dendrites; Female; Ganglia, Sympathetic; Immunohistochemistry; Male; Membrane Potentials; Mice; Mice, Inbred BALB C; Neurons; Neuropeptide Y; Organ Specificity; Patch-Clamp Techniques; Superior Cervical Ganglion; Tyrosine 3-Monooxygenase; Vasoactive Intestinal Peptide
PubMed: 10561442
DOI: 10.1152/jn.1999.82.5.2747 -
Cells Jul 2022The purinergic system plays an important role in pain transmission. Recent studies have suggested that activation of P2-purinergic receptors (P2Rs) may be involved in...
The purinergic system plays an important role in pain transmission. Recent studies have suggested that activation of P2-purinergic receptors (P2Rs) may be involved in neuron-satellite glial cell (SGC) interactions in the dorsal root ganglia (DRG), but the details remain unclear. In DRG, P2X7R is selectively expressed in SGCs, which closely surround neurons, and is highly sensitive to 3'-O-(4-Benzoyl) benzoyl-ATP (BzATP). Using calcium imaging in intact mice to survey a large number of DRG neurons and SGCs, we examined how intra-ganglionic purinergic signaling initiated by BzATP affects neuronal activities in vivo. We developed -GCaMP6s and -GCaMP6s mice to express the genetically encoded calcium indicator GGCaM6s in SGCs and DRG neurons, respectively. The application of BzATP to the ganglion induced concentration-dependent activation of SGCs in -GCaMP6s mice. In -GCaMP6s mice, BzATP initially activated more large-size neurons than small-size ones. Both glial and neuronal responses to BzATP were blocked by A438079, a P2X7R-selective antagonist. Moreover, blockers to pannexin1 channels (probenecid) and P2X3R (A317491) also reduced the actions of BzATP, suggesting that P2X7R stimulation may induce the opening of pannexin1 channels, leading to paracrine ATP release, which could further excite neurons by acting on P2X3Rs. Importantly, BzATP increased the responses of small-size DRG neurons and wide-dynamic range spinal neurons to subsequent peripheral stimuli. Our findings suggest that intra-ganglionic purinergic signaling initiated by P2X7R activation could trigger SGC-neuron interaction in vivo and increase DRG neuron excitability.
Topics: Adenosine Triphosphate; Animals; Calcium; Ganglia, Spinal; Mice; Neuroglia; Neurons
PubMed: 35892578
DOI: 10.3390/cells11152280 -
Genesis (New York, N.Y. : 2000) Jan 2019The cranial trigeminal ganglia play a vital role in the peripheral nervous system through their relay of sensory information from the vertebrate head to the brain. These...
The cranial trigeminal ganglia play a vital role in the peripheral nervous system through their relay of sensory information from the vertebrate head to the brain. These ganglia are generated from the intermixing and coalescence of two distinct cell populations: cranial neural crest cells and placodal neurons. Trigeminal ganglion assembly requires the formation of cadherin-based adherens junctions within the neural crest cell and placodal neuron populations; however, the molecular composition of these adherens junctions is still unknown. Herein, we aimed to define the spatio-temporal expression pattern and function of Cadherin-7 during early chick trigeminal ganglion formation. Our data reveal that Cadherin-7 is expressed exclusively in migratory cranial neural crest cells and is absent from trigeminal neurons. Using molecular perturbation experiments, we demonstrate that modulation of Cadherin-7 in neural crest cells influences trigeminal ganglion assembly, including the organization of neural crest cells and placodal neurons within the ganglionic anlage. Moreover, alterations in Cadherin-7 levels lead to changes in the morphology of trigeminal neurons. Taken together, these findings provide additional insight into the role of cadherin-based adhesion in trigeminal ganglion formation, and, more broadly, the molecular mechanisms that orchestrate the cellular interactions essential for cranial gangliogenesis.
Topics: Adherens Junctions; Animals; Avian Proteins; Cadherins; Chick Embryo; Neural Crest; Neurogenesis; Neurons; Trigeminal Ganglion
PubMed: 30461190
DOI: 10.1002/dvg.23264 -
The Journal of Biological Chemistry Oct 1998gamma-Aminobutyric acid type B (GABAB) receptors mediate the transmission of slow and prolonged inhibitory signals in the central nervous system. Two splice variants of...
gamma-Aminobutyric acid type B (GABAB) receptors mediate the transmission of slow and prolonged inhibitory signals in the central nervous system. Two splice variants of GABAB receptors, GABABR1a and GABABR1b, were recently cloned from a mouse cortical and cerebellar cDNA library. As predicted, these receptors belong to the G protein-coupled receptor superfamily. We have used epitope-tagged versions of GABABR1a receptors to study the cellular distribution of these proteins in a variety of non-neuronal and neuronal cell types. Here we report that recombinant GABAB receptors fail to reach the cell surface when expressed in heterologous systems and are retained in the endoplasmic reticulum when introduced into COS cells. In addition, we prove that recombinant GABAB receptors are excluded from the cell surface when overexpressed in ganglion neurons and we further demonstrate that they fail to activate in superior cervical ganglion neurons. Together our observations suggest that recombinant GABAB receptors require additional information for functional targeting to the plasma membrane.
Topics: Animals; Base Sequence; COS Cells; Cell Membrane; Cricetinae; DNA Primers; Endoplasmic Reticulum; Ganglia; Humans; Mice; Mutagenesis, Site-Directed; Neurons; Receptors, GABA-B; Recombinant Proteins
PubMed: 9756866
DOI: 10.1074/jbc.273.41.26361 -
Proceedings of the National Academy of... Aug 2017Children with Rett syndrome show abnormal cutaneous sensitivity. The precise nature of sensory abnormalities and underlying molecular mechanisms remain largely unknown....
Children with Rett syndrome show abnormal cutaneous sensitivity. The precise nature of sensory abnormalities and underlying molecular mechanisms remain largely unknown. Rats with methyl-CpG binding protein 2 (MeCP2) mutation, characteristic of Rett syndrome, show hypersensitivity to pressure and cold, but hyposensitivity to heat. They also show cutaneous hyperinnervation by nonpeptidergic sensory axons, which include subpopulations encoding noxious mechanical and cold stimuli, whereas peptidergic thermosensory innervation is reduced. MeCP2 knockdown confined to dorsal root ganglion sensory neurons replicated this phenotype in vivo, and cultured MeCP2-deficient ganglion neurons showed augmented axonogenesis. Transcriptome analysis revealed dysregulation of genes associated with cytoskeletal dynamics, particularly those controlling actin polymerization and focal-adhesion formation necessary for axon growth and mechanosensory transduction. Down-regulation of these genes by topoisomerase inhibition prevented abnormal axon sprouting. We identified eight key affected genes controlling actin signaling and adhesion formation, including members of the Arhgap, Tiam, and cadherin families. Simultaneous virally mediated knockdown of these genes in Rett rats prevented sensory hyperinnervation and reversed mechanical hypersensitivity, indicating a causal role in abnormal outgrowth and sensitivity. Thus, MeCP2 regulates ganglion neuronal genes controlling cytoskeletal dynamics, which in turn determines axon outgrowth and mechanosensory function and may contribute to altered pain sensitivity in Rett syndrome.
Topics: Animals; Axons; Cytoskeletal Proteins; Cytoskeleton; Down-Regulation; Ganglion Cysts; Humans; Methyl-CpG-Binding Protein 2; Mutation; Rats; Rats, Mutant Strains; Rett Syndrome
PubMed: 28760966
DOI: 10.1073/pnas.1618210114