Erratum: Megat et al., “Differences between Dorsal Root and Trigeminal Ganglion Nociceptors in Mice Revealed by Translational Profiling”

Background A common characteristic of migraine-inducing substances is that they cause headache and no pain in other areas of the body. Few studies have compared pain mechanisms in the trigeminal and spinal systems and, so far, no major differences have been noted. We compared signalling molecules in the trigeminal and spinothalamic system after infusion of the migraine-provoking substance glyceryltrinitrate. Method A catheter was placed in the femoral vein of rats and one week later glyceryltrinitrate 4 µg/kg/min was infused for 20 min. Protein expression in the dura mater, trigeminal ganglion, nucleus caudalis, dorsal root ganglion and the dorsal horn of the thoracic spinal cord was analysed at different time points using western blotting and immunohistochemistry. Results Glyceryltrinitrate caused a threefold increase in expression of phosphorylated extracellular signal-regulated kinases at 30 min in the dura mater and nucleus caudalis ( P < 0.05) and at 2 h in the trigeminal ganglion with very few expressions in the dorsal root ganglion. In the nucleus caudalis, expression of phosphorylated extracellular signal-regulated kinases and Cam KII increased 2.6-fold and 3.2-fold, respectively, at 2 h after glycerytrinitrate infusion ( P < 0.01). p-CREB/ATF-1 upregulation was observed only at 30 min ( P < 0.05) in the nucleus caudalis. None of these markers showed increased expression in the regions of thoracic spinal cord dorsal horn. Conclusion The dura, trigeminal ganglion and nucleus caudalis are activated shortly after glycerytrinitrate infusion with long-lasting expression of phosphorylated extracellular signal-regulated kinases observed in the nucleus caudalis. These activations were not observed at the spinal level.

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Retrograde Tracing of Nerve Fibers to the Rat Middle Cerebral Artery with True Blue: Colocalization with Different Peptides

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1989.31 ◽

1989 ◽

Vol 9 (2) ◽

pp. 212-218 ◽

Cited By ~ 142

Author(s):

L. Edvinsson ◽

H. Hara ◽

R. Uddman

Keyword(s):

Dorsal Root Ganglion ◽

Middle Cerebral Artery ◽

Nerve Cell ◽

Trigeminal Ganglion ◽

Cerebral Artery ◽

Superior Cervical Ganglion ◽

Dorsal Root ◽

Nerve Fibers ◽

Retrograde Tracing ◽

Cervical Ganglion

The origin of nerve fibers to the rat middle cerebral artery was studied by retrograde tracing with the fluorescent tracer True Blue (TB) in combination with immunocytochemistry to known perivascular peptides. Application of TB to the middle cerebral artery labeled nerve cell bodies in the ipsilateral superior cervical ganglion, the otic ganglion, the sphenopalatine ganglion, the trigeminal ganglion, and the cervical dorsal root ganglion at level C2. A few labeled nerve cell bodies were seen in contralateral ganglia. Judging from the number and intensity of the labeling, the superior cervical ganglion and the trigeminal ganglion and dorsal root ganglion at level C2 contributed most to the innervation. A moderate number of nerve cell bodies were labeled in the sphenopalatine and otic ganglia. The TB-labeled nerve cell bodies were further examined for the presence of neuropeptides. For that purpose antibodies raised against neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP), substance P (SP) and calcitonin gene-related peptide (CGRP) were used. A considerable portion of the TB-labeled nerve cell bodies in the superior cervical ganglion contained NPY. About half of the labeled nerve cell bodies in the sphenopalatine and otic ganglia contained VIP. In the trigeminal ganglion and in the dorsal root ganglion at level C2, one-third of the TB-labeled nerve cell bodies were CGRP-immunoreactive, while only few nerve cell bodies contained SP. The study provides direct evidence for the origin of cerebrovascular peptidergic nerve fibers and demonstrates that not only ipsilateral but also contralateral ganglia contribute to the innervation of the cerebral circulation.

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Differences between Dorsal Root and Trigeminal Ganglion Nociceptors in Mice Revealed by Translational Profiling

Journal of Neuroscience ◽

10.1523/jneurosci.2663-18.2019 ◽

2019 ◽

Vol 39 (35) ◽

pp. 6829-6847 ◽

Cited By ~ 20

Author(s):

Salim Megat ◽

Pradipta R. Ray ◽

Diana Tavares-Ferreira ◽

Jamie K. Moy ◽

Ishwarya Sankaranarayanan ◽

...

Keyword(s):

Trigeminal Ganglion ◽

Dorsal Root

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TLR8 in the Trigeminal Ganglion Contributes to the Maintenance of Trigeminal Neuropathic Pain in Mice

Neuroscience Bulletin ◽

10.1007/s12264-020-00621-4 ◽

2020 ◽

Author(s):

Lin-Xia Zhao ◽

Ming Jiang ◽

Xue-Qiang Bai ◽

De-Li Cao ◽

Xiao-Bo Wu ◽

...

Keyword(s):

Neuropathic Pain ◽

Inflammatory Cytokines ◽

Trigeminal Ganglion ◽

Dorsal Root ◽

Mechanical Allodynia ◽

Infraorbital Nerve ◽

Trigeminal Neuropathic Pain ◽

Intracellular Ca ◽

Significant Health ◽

Pro Inflammatory Cytokines

AbstractTrigeminal neuropathic pain (TNP) is a significant health problem but the involved mechanism has not been completely elucidated. Toll-like receptors (TLRs) have recently been demonstrated to be expressed in the dorsal root ganglion and involved in chronic pain. Here, we show that TLR8 was persistently increased in the trigeminal ganglion (TG) neurons in model of TNP induced by partial infraorbital nerve ligation (pIONL). In addition, deletion or knockdown of Tlr8 in the TG attenuated pIONL-induced mechanical allodynia, reduced the activation of ERK and p38-MAPK, and decreased the expression of pro-inflammatory cytokines in the TG. Furthermore, intra-TG injection of the TLR8 agonist VTX-2337 induced pain hypersensitivity. VTX-2337 also increased the intracellular Ca2+ concentration, induced the activation of ERK and p38, and increased the expression of pro-inflammatory cytokines in the TG. These data indicate that TLR8 contributes to the maintenance of TNP through increasing MAPK-mediated neuroinflammation. Targeting TLR8 signaling may be effective for the treatment of TNP.

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Prion type 2 selection in sporadic Creutzfeldt–Jakob disease affecting peripheral ganglia

Acta Neuropathologica Communications ◽

10.1186/s40478-021-01286-4 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Anna Hofmann ◽

Arne Wrede ◽

Wiebke M. Jürgens-Wemheuer ◽

Walter J. Schulz-Schaeffer

Keyword(s):

Central Nervous System ◽

Prion Protein ◽

Trigeminal Ganglion ◽

Dorsal Root ◽

Pathological Changes ◽

Jakob Disease ◽

The Central Nervous System ◽

Dependent Property

AbstractIn sporadic Creutzfeldt–Jakob disease (sCJD), the pathological changes appear to be restricted to the central nervous system. Only involvement of the trigeminal ganglion is widely accepted. The present study systematically examined the involvement of peripheral ganglia in sCJD utilizing the currently most sensitive technique for detecting prions in tissue morphologically. The trigeminal, nodose, stellate, and celiac ganglia, as well as ganglia of the cervical, thoracic and lumbar sympathetic trunk of 40 patients were analyzed with the paraffin-embedded tissue (PET)-blot method. Apart from the trigeminal ganglion, which contained protein aggregates in five of 19 prion type 1 patients, evidence of prion protein aggregation was only found in patients associated with type 2 prions. With the PET-blot, aggregates of prion protein type 2 were found in all trigeminal (17/17), in some nodose (5 of 7) and thoracic (3 of 6) ganglia, as well as in a few celiac (4 of 19) and lumbar (1 of 5) ganglia of sCJD patients. Whereas aggregates of both prion types may spread to dorsal root ganglia, more CNS-distant ganglia seem to be only involved in patients accumulating prion type 2. Whether the prion type association is due to selection by prion type-dependent replication, or due to a prion type-dependent property of axonal spread remains to be resolved in further studies.

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Membrane-associated microtubular areays induced in proximal myelinated processes of dorsal root ganglia by large doses of vitamin B6

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143468 ◽

1986 ◽

Vol 44 ◽

pp. 368-369

Author(s):

V.J. Montpetit ◽

S. Dancea ◽

L. Tryphonas ◽

D.F. Clapin

Keyword(s):

Animal Model ◽

Endoplasmic Reticulum ◽

Dorsal Root Ganglia ◽

Rough Endoplasmic Reticulum ◽

Dorsal Root ◽

Vitamin B6 ◽

Morphological Changes ◽

Model System ◽

Sensory Nerves ◽

Peripheral Sensory

Very large doses of pyridoxine (vitamin B6) are neurotoxic in humans, selectively affecting the peripheral sensory nerves. We have undertaken a study of the morphological and biochemical aspects of pyridoxine neurotoxicity in an animal model system. Early morphological changes in dorsal root ganglia (DRG) associated with pyridoxine megadoses include proliferation of neurofilaments, ribosomes, rough endoplasmic reticulum, and Golgi complexes. We present in this report evidence of the formation of unique aggregates of microtubules and membranes in the proximal processes of DRG which are induced by high levels of pyridoxine.

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