After ipsilateral injections of biotinylated dextran amine (BDA) into the PLH and CTb into the motor trigeminal nucleus (Vm), the prominent distribution of BDA-labeled axon terminals around CTb-labeled neurons was found in the RFp region just ventral to the nucleus of the solitary tract and medial to the spinal trigeminal nucleus ipsilateral to the injection sites. 
The retrograde tracer fluorogold was injected in the magnocellular part of the red nucleus, and the number of labeled neurons in the oral part of the spinal trigeminal nucleus (Sp5O) was counted.
In the present study, we describe GABAA receptor-mediated tonic inhibitory currents in the substantia gelatinosa (SG) region of rat spinal trigeminal nucleus pars caudalis (Vc).
Pain behavior testing together with immunostaining for markers of nerve injury in the spinal trigeminal nucleus show the suitability of this procedure as a model of orofacial pain..
To examine the central connections of MesV, biotinylated dextran amine (BDA) was injected into the spinal trigeminal nucleus (Vs).
Labeled terminals were identified throughout the rostrocaudal extent of the TBNC, including the principal nucleus (Pr5), pars oralis (Sp5O), pars interpolaris (Sp5I), and pars caudalis (Sp5C) of the spinal trigeminal nucleus.
A high density of PTH2R-immunoreactive fibers was found in brain regions of the medulla oblongata including the nucleus of the solitary tract, the spinal trigeminal nucleus, and the dorsal reticular nucleus of the medulla.
This would activate the brainstem-spinal descending 5HT systems and, in effect, suppress nociceptive signals from primary afferent neurons to the spinal trigeminal nucleus caudalis..
A high density of calcitonin gene-related peptide-immunoreactive perikarya was found in the superior colliculus, the dorsal nucleus of the raphe, the trochlear nucleus, the lateral division of the marginal nucleus of the brachium conjunctivum, the motor trigeminal nucleus, the facial nucleus, the pons reticular formation, the retrofacial nucleus, the rostral hypoglossal nucleus, and in the motor dorsal nucleus of the vagus, whereas a high density of fibers containing calcitonin gene-related peptide was observed in the lateral division of the marginal nucleus of the brachium conjunctivum, the parvocellular division of the alaminar spinal trigeminal nucleus, the external cuneate nucleus, the nucleus of the solitary tract, the laminar spinal trigeminal nucleus, and in the area postrema.
Pain-related behavior and neuronal activation in the spinal trigeminal nucleus were enhanced on both sides compared to those in non-inflammatory controls.
Labeled nerve terminations were found ipsilaterally in the lateral part of the spinal dorsal horn of segments C1-C3 and in the caudal and interpolar parts of the spinal trigeminal nucleus. These results indicate that sensory information from the MMA is transmitted through both trigeminal and cervical spinal nerve branches to a region in the central nervous system extending rostrally from the C3 dorsal horn to the interpolar part of the spinal trigeminal nucleus.
Relative levels of AEA and 2-AG varied from region to region, with the 2-AG:AEA ratio being high in the sensory spinal trigeminal nucleus (140:1), the spinal dorsal horn (136:1) and the lateral hypothalamus (98:1) and low in the nucleus accumbens (16:1) and the striatum (31:1).
Unilateral injection of 100 microl 1% lidocaine into the trigeminal Gasser ganglion of narcotized rats produced a long-term moderation of the discharge rate of neurons in the ipsilateral (relative to the side of injection) rostral area of the spinal trigeminal nucleus. Activity of neurons in the contralateral rostral area of the spinal trigeminal nucleus was not blocked. Functional state of neurons in the trigeminal ganglion determines discharge activity of ipsilateral neurons of the spinal trigeminal nucleus. Activity of neurons in the contralateral rostral area of spinal trigeminal nucleus was not inhibited. Functional state of the cells in the trigeminal ganglion determines the character of electrical activity of neurons in the ipsilateral rostral area of spinal trigeminal nucleus..
In the spinal trigeminal nucleus, CLR- and RAMP1-ir was localized to "glomerular structures," partly colocalized with CGRP-ir. In the spinal trigeminal nucleus, CGRP receptors are probably located on neuronal processes, including primary afferent endings, suggesting involvement in presynaptic regulation of nociceptive transmission.
The aim of the present study was to examine if ongoing activity of neurons in different subnuclei of the spinal trigeminal nucleus is driven from peripheral afferent input. Ongoing activity of single wide-dynamic range (WDR) neurons was recorded with carbon fiber glass microelectrodes in two subnuclei of the spinal trigeminal nucleus: oral (Sp5O) and caudal (Sp5C). We conclude that the ongoing activity of WDR neurons in the spinal trigeminal nucleus, which may be indicative for processes of sensitization, is driven remotely by ongoing afferent input..
As a model we used the rat spinal trigeminal nucleus, in which the subnucleus oralis (Sp5O) contains a pool of WDR neurons that receive their nociceptive C-input indirectly via interneurons located in the medullary dorsal horn (MDH).
Electrical stimulation of the pinna induced significant increases in the number of Fos-positive neurons in the DCN, spinal trigeminal nucleus (Sp5), dorsal raphe nucleus (DR) and locus coeruleus (LC).
The trigeminal and dorsal root ganglia relay afferent somatosensory information from the periphery to secondary sensory neurons in the brainstem, specifically, the spinal trigeminal nucleus and dorsal column nuclei, respectively.
The three brainstem regions examined included the mid-brain periaqueductal gray (PAG), the medullary nucleus raphe magnus (NRM), and the spinal trigeminal nucleus (STN).
spinal trigeminal nucleus (Vsp) consists of three subnuclei: oralis (Vo), interpolaris (Vi) and caudalis (Vc).
Gustatory neurons innervate taste buds and project centrally to the rostral nucleus of the solitary tract (NTS), whereas neurons providing general epithelial innervation to the oropharynx project to non-gustatory hindbrain regions, i.e., spinal trigeminal nucleus.
Furthermore, the spinal trigeminal nucleus, the lateral reticular nucleus (LRT) and the hypoglossal nucleus demonstrated intense EYFP expression whereas other regions of the medulla were devoid of neuronal EYFP labeling (e.g.
In the medulla oblongata, Phox2b-immunoreactive nuclei were present in the dorsal vagal complex, intermediate reticular nucleus, dorsomedial spinal trigeminal nucleus, nucleus ambiguus, catecholaminergic neurons, and retrotrapezoid nucleus (RTN). This marker identifies a subset of hindbrain neurons that control orofacial movements (dorsomedial spinal trigeminal nucleus, pontine peritrigeminal neurons), balance and auditory function (vestibulocochlear efferents), the eyes, and both divisions of the autonomic efferent system.
Mast cell-induced nociceptor interaction was also associated with downstream activation of the spinal trigeminal nucleus as indicated by an increase in c-fos expression.
Moreover, immunohistochemistry detected a reduction in LPS-induced Fos-like immunoreactivity expression in the subnucleus caudalis of spinal trigeminal nucleus and in the preoptic area of the hypothalamus (POA) in tolerant rats compared with non-tolerant animals, indicating that the endotoxin tolerance may be locally mediated in the periodontal protection tissues of rats..
Using fMRI we mapped changes in the spinal trigeminal nucleus (spV), and supraspinal brainstem nuclei following heat/capsaicin-induced primary and secondary dynamic mechanical allodynia in the human trigeminal system.
Injection of 200 nL 2% fluorogold into the red nucleus caused labeling in the mesencephalic trigeminal nucleus, the principal sensory nucleus and the oral, interpolar, and caudal subnuclei of the spinal trigeminal nucleus in both control and mdx mice. In the oral subnucleus of the spinal trigeminal nucleus this reduction was 50%.
Lower portions of the spinal cord downwards of the fourth thoracic segment appeared to be predominantly affected, whereas the spinal trigeminal nucleus was virtually intact.
RESULTS: FPCs in the spinal trigeminal nucleus, the parvocellular reticular nucleus, and the nucleus of the solitary tract were more frequent than the sham-operated rats.
Neurons located in the border region between the interpolaris and caudalis subdivisions of the spinal trigeminal nucleus (Vi/Vc) are second order neurons of the corneal reflex, receiving corneal afferents and projecting to the lid closing, orbicularis oculi (OO) motoneurons.
Projections of glutamatergic somatosensory and auditory fibers to the cochlear nucleus (CN) are mostly nonoverlapping: projections from the spinal trigeminal nucleus (Sp5) terminate primarily in the granule cell domains (GCD) of CN, whereas type I auditory nerve fibers (ANFs) project to the magnocellular areas of the VCN (VCNm) and deep layers of Dorsal CN (DCN).
It has been reported that the spinal trigeminal nucleus caudalis (Sp5C), which receives nociceptive information from the oro-facial regions, has four laminae.
In addition, we found that a subpopulation of the interpolar subnucleus of the spinal trigeminal nucleus, which projects the axons to the cerebellum, was one of the PCNs derived from the LRL.
Using transmission electron microscopy, our study also shows that BDNF-immunoreactivity is present in dense core vesicles of unmyelinated axons and axon terminals in the subnucleus caudalis of the spinal trigeminal nucleus, the primary central target of trigeminal nociceptors.
Activation in the spinal trigeminal nucleus was constant in location for all pain stimuli.
Our study describes for the first time distribution of Pax-5 in adult brain tissue, including periaqueductal gray matter of the midbrain, area postrema of the medulla oblongata, and occasional cells of the spinal trigeminal nucleus (caudal nucleus).
Lamina I and II of the spinal trigeminal nucleus also project to the external lateral and the extreme lateral subnuclei of the parabrachial nucleus.
BACKGROUND: Based largely on data from animal models, migraine is hypothesized to involve changes in neural function in brain areas that mediate nociception--specifically, the trigeminal nerve, spinal trigeminal nucleus, and thalamus.
Moreover, immunohistochemistry detected c-fos expression in the subnucleus caudalis of spinal trigeminal nucleus and in the preoptic area of the hypothalamus 2 and 3 h after LPS injection, further confirming the role of trigeminal nerve signaling brain in acute periodontitis..
For the medullary dorsal horn (caudal subnucleus of spinal trigeminal nucleus: Vc), however, the existence of such neurons has not been reported.
Electrostimulation of the masseter nerve evoked short-latency responses (5.86 +/- 2.59 ms) in hypoglossal premotor pools including the parvocellular (PCRt) and intermediate (IRt) reticular nuclei and the dorsomedial part of the spinal trigeminal nucleus oralis (Vodm) and interpolaris (Vidm).
Following selective injections of Fluoro-Gold in the Am, retrogradely labeled neurons were observed in parasubthalamic nucleus, peripeduncular nucleus, periaqueductal gray, dopaminergic nuclear complex (substantia nigra pars lateralis and pars compacta, paranigral, parabrachial pigmented and interfascicular nuclei, rostral and caudal linear nuclei, retrorubral area), deep mesencephalic nucleus, serotoninergic structures (dorsal, median and pontine raphe nuclei), laterodorsal and pedunculopontine tegmental nuclei (Ch6 and Ch5 groups), parabrachial nuclear complex, locus coeruleus, nucleus incertus, ventrolateral pontine tegmentum (A5 group), dorsomedial medulla (nucleus of the solitary tract, A2 group), ventrolateral medulla (A1/C1 group), and pars caudalis of the spinal trigeminal nucleus.
Neuroanatomical experiments showed evidence for reciprocal neuronal pathways connecting the locus coeruleus (LC) to trigeminal sensory nuclei and linking monoaminergic nuclei of the pain inhibitory system to spinal trigeminal nucleus (STN).
The cochlear nucleus (CN) receives innervation from trigeminal sensory structures: the ophthalmic division of the trigeminal ganglion and the caudal and interpolar regions of the spinal trigeminal nucleus (Sp5I and Sp5C).
HCN1-IR neurons in the brainstem included neurons in sensory pathways such as the dorsal column nuclei, the area postrema, the spinal trigeminal nucleus as well as identified motor neurons in motor nuclei.
We have evidence that there is a high intensity of Gamma-aminobutyric acid transporters in the trigeminal sensory nuclei, and that Gamma-aminobutyric transporters expression was increased in the spinal trigeminal nucleus of rats after facial carrageenan injections. These are correlated with increased Gamma-aminobutyric acid uptake in the synaptosomal preparation from the spinal trigeminal nucleus of rats that received the injections and can be antagonised with glial uptake inhibitors.
The phosphorylated Extracellular Signal-regulated Kinase (pERK) and Fos expression and masticatory muscle activity were analyzed in rats with capsaicin-induced acute inflammation of the tooth pulp in order to clarify the role of the spinal trigeminal nucleus and upper cervical spinal cord in tooth pulp pain. The present findings suggest that tooth-pulp-driven neurons in the spinal trigeminal nucleus are involved in tooth pulp pain through activation of the intracellular signal transduction pathway that involves earlier ERK phosphorylation and subsequent Fos expression..
To elucidate the extent of interaction between auditory and somatosensory representations at the level of IC, we explored the dual projections from the cochlear nucleus (CN) and the spinal trigeminal nucleus (Sp5) to the inferior colliculus (IC) in the guinea pig, using both retrograde and anterograde tracing techniques.
Dual immunohistochemistry revealed that some Kv3.3-IR neurones in the ventral medullary reticular nucleus, spinal trigeminal nucleus, dorsal horn, ventral horn and central canal region were also immunoreactive for the Kv3.1b subunit.
MRIs were evaluated blindly to clinical features to determine extension of the infarct to presumed topographies of the ventral trigeminothalamic (VTT), lateral spinothalamic, spinal trigeminal tracts and spinal trigeminal nucleus.
In the guinea pig, both the spinal trigeminal nucleus (TN) and the cochlear nucleus converge in the ventrolateral region of ICx.
In diabetic rats, B(2) receptor densities were significantly increased in lamina l of the dorsal horn (+35% at 7 and 21 days), spinal trigeminal nucleus (+70% at 7 and 21 days) and nucleus tractus solitarius (+100% at 2 and 7 days).
Using immunocytochemical methods, we find that activity changes in spinal trigeminal nucleus neurons could underlie at least part of the VNS-induced analgesia..
In the present study, we used Fos expression as an index of nociceptive input to the spinal trigeminal nucleus after exposure of the coronal pulp tissue of maxillary right first molars and examined the effects of pretreatment with an opioid, a nonsteroidal anti-inflammatory drug or a local anesthetic before pulp exposure.
BACKGROUND: The majority of migraineurs seeking secondary or tertiary medical care develop cutaneous allodynia during the course of migraine, a sensory abnormality mediated by sensitization of central trigeminovascular neurons in the spinal trigeminal nucleus.
Three experiments were conducted in order to investigate the possible involvement of the reactive oxygen species in the nociception within the subnucleus caudalis of the spinal trigeminal nucleus (Vc).
Here, we took advantage of the fact that lesions of the spinal trigeminal nucleus interpolaris (SpVi) significantly reduce the receptive field size of neurons in the ventroposterior thalamus.
CGRP may be involved in the control of neuronal activity in the spinal trigeminal nucleus (STN), which integrates nociceptive afferent inputs from trigeminal tissues, including intracranial afferents.
GIR mRNA showed widespread distribution in forebrain limbic and thalamic structures, and a more restricted distribution in hindbrain areas such as the spinal trigeminal nucleus and the median raphe nucleus.
They mainly project to the ventral and dorsal parts of the spinal trigeminal nucleus but not to the principal nucleus. Additional neurons located in the middle NTS were found to project exclusively to the spinal trigeminal nucleus pars caudalis.
In urethane-anesthetized rats, the jaw opening reflex (JOR) was produced by suprathreshold stimulation of the tooth pulp and measured as electromyographic response in the digastric muscle, with simultaneous recording of noxious responses in single unit neurons of the spinal trigeminal nucleus pars caudalis (Sp5c).
Inputs to the granule cell domain (GCD) of the cochlear nucleus have been shown to arise from somatosensory brain stem structures, but the nature of the projection from the spinal trigeminal nucleus is unknown. In a second set of experiments, we injected the anterograde tracer biotinylated dextran amine into the spinal trigeminal nucleus and studied the resulting anterograde projections with light and electron microscopy.
Recent evidence has been accumulated that not only spinal trigeminal nucleus caudalis (Sp5C) neurons but also spinal trigeminal nucleus oralis (Sp5O) neurons respond to noxious stimuli.
Subcortical moderate to weak projections reach the PAG from the central and medial amygdala, nucleus of the stria terminalis, septum, nucleus accumbens, lateral preoptic region, lateral and posterior hypothalamus, globus pallidus, pretectal area, deep layers of the superior colliculus, the pericentral inferior colliculus, mesencephalic trigeminal nucleus, locus coeruleus, substantia nigra pars compacta, dorsal and ventral raphe, vestibular nuclei, spinal trigeminal nucleus, solitary tract nucleus, and nucleus gracilis.
Sparser projections were found ipsilaterally in the pressor and depressor areas of the medulla and the spinal trigeminal nucleus and contralaterally in the CPA.
Both DOR and MOR-like immunoreactive processes were observed in other brainstem areas such as the spinal trigeminal nucleus.
KCC2 mRNA was expressed in the motor trigeminal nucleus (Mo5), the principal trigeminal nucleus (Pr5), and the spinal trigeminal nucleus (Sp5), but not in the trigeminal ganglion (TG) and the mesencephalic trigeminal nucleus (Me5).
FLI was also observed in the gigantocellular tegmental field (FTG -- medial nuclei of reticular formation), the spinal trigeminal nucleus, in the medullar raphe nuclei (ncl.
Within the medulla oblongata, labeled cells were detected in the facial, ambiguus, prepositus, lateral paragigantocellular and lateral reticular nuclei, and spinal trigeminal nucleus.
In addition to olfactory neurons, the nasal cavity is innervated by the maxillary division of the trigeminal nerve that projects to the spinal trigeminal nucleus. Mn concentrations in the trigeminal ganglia and spinal trigeminal nucleus were measured 2 h (0-day), 7-, 14-, or 30-days post-exposure using proton induced X-ray emission (PIXE). We also found a small but significant elevation of Mn in the spinal trigeminal nucleus of mice 7-days post-exposure and in rats 0- and 7-days post-exposure.
In the brainstem, labeled terminations were mainly found in the caudal and interpolar parts of the spinal trigeminal nucleus. These results indicate that the sensory information from the SSS is transmitted through both trigeminal and cervical spinal nerve branches to a primary sensory nervous center that extends from the C3 dorsal horn until to the interpolar part of the spinal trigeminal nucleus..
We continue this line of study by investigating the projection from the spinal trigeminal nucleus to CN in guinea pig. The anterograde tracers Fluoro-Ruby or BDA were stereotaxically injected into the spinal trigeminal nucleus.
The caudal part (nucleus caudalis) of the spinal trigeminal nucleus is considered to be the site of the second order neurons of the nociceptive pathways of the face. The marginal and interstitial plexuses can represent the framework for modulation and vertical signal transmission within the spinal trigeminal nucleus, while the magnocellular layers seem to be mainly responsible for contralateral projection. It seems that the outer laminae of the spinal trigeminal nucleus may represent the receiver and the inner laminae the transmitter of the signal on the trigeminal pathway at brainstem level..
The highest density of immunoreactive fibers containing methionine-enkephalin-Arg(6)-Gly(7)-Leu(8) was found in the spinal trigeminal nucleus, the central gray and the reticular formation of the medulla oblongata, pons and mesencephalon, the solitary nucleus, the spinal vestibular nucleus, the dorsal accessory olivary nucleus, the raphe obscurus, the substantia nigra and in the interpeduncular nucleus.
It is now possible to use functional magnetic resonance imaging (fMRI) to measure CNS activation in the trigeminal ganglion, spinal trigeminal nucleus, the thalamus, and the somatosensory cortex in healthy volunteers, in a surrogate model of hyperalgesia, and in patients with trigeminal pain.
This study examined the cellular actions of the anti-migraine drug sumatriptan, on neurons in the substantia gelatinosa of the spinal trigeminal nucleus pars caudalis.
The late R2-like component of abducens nerve responses is mediated by the spinal trigeminal nucleus in the medulla.
The organization of the efferent projections from the spinal trigeminal nucleus oralis (Sp5O) to the diencephalon was studied in the rat using the anterograde tracer Phaseolus vulgaris leucoagglutinin.
The aim of this experiment was to investigate the role of the gamma-aminobutyric acid (GABA)-ergic transmission in the nociception within the spinal trigeminal nucleus.
Increasing the frequency of stimulation induced c-Fos expression in further nuclei such as the parabrachial nucleus (PBN), the inferior olive subnuclei (IOn), the oral part of spinal trigeminal nucleus (Sp5O) and locus coeruleus (LC).
The prominent overlapping distribution of these labeled axons and neurons was found in the RFp region just ventral to the nucleus of the solitary tract and medial to the spinal trigeminal nucleus throughout the caudalmost part of the pons and the rostral half of the medulla oblongata.
The present experiments were undertaken to separate the contribution of the principal trigeminal nucleus (PrV) from that of the spinal trigeminal nucleus (SpV) to whisker evoked responses in the ventral posterior medial (VPM) nucleus in the adult rat thalamus.
Histological damage was found in CB and the spinal trigeminal nucleus (located in the pontomedullar brainstem).
In awake rats, startle responses evoked by either acoustic or spinal trigeminal nucleus stimulation were inhibited by kynurenate, but not saline, infusions, with the most effective placements nearest PnC.
An access to the medullary brain stem allowed extracellular action potentials to be recorded from neurons in the spinal trigeminal nucleus that received afferent input from the exposed dura.
This protocol allowed us to demonstrate that dense p55-immunoreactivity (p55-ir) is constitutively present on central (but not peripheral) vagal afferents in the solitary tract (ST) and nucleus; p55-ir is also present on afferents entering the spinal trigeminal nucleus.
In anaesthetized rats, extracellular recordings were made from neurones of the spinal trigeminal nucleus, involved in the processing of nociceptive input from the dura.
In addition to the cerebellum, strong to medium ROR alpha immunoreactivity was found in the thalamus, cerebral cortex (mainly in the layer IV), dorsal cochlear nucleus (DCN), suprachiasmatic nucleus (SCN), superior colliculus, spinal trigeminal nucleus, and retina.
Somatic sensory influences from the dorsal column nuclei and spinal trigeminal nucleus are the primary ascending sensory input to the external cortex; ascending auditory input to layer 2 is sparse.
In recent years, we have accumulated data showing that the spinal trigeminal nucleus oralis (Sp5O) contributes to the processing of somatosensory inputs from the orofacial region.
In the present study, the cannabinoid CB1/CB2 receptor agonist, WIN 55,212-2 (WIN), was bath applied to the brainstem while activity of spinal trigeminal nucleus caudalis (Vc) neurons evoked by transcutaneous electrical stimulation was recorded in isoflurane anesthetized rats.
Sema3A expression was up-regulated in the contralateral cerebral cortex and in the ipsilateral spinal trigeminal nucleus 1-3 days after spinal cord hemisection.
CB(1) receptors have been found localized on fibers in the spinal trigeminal tract and spinal trigeminal nucleus caudalis.
High concentrations were also detected in other hypothamamic nuclei, the inferior colliculus, the ventral central gray matter, the pontine tegmentum, the amygdala, the reticular formation and the spinal trigeminal nucleus.
The VLMlat, the reticular formation located between the spinal trigeminal nucleus and the lateral reticular nucleus (LRt), appears to play a major role in that antinociceptive action.
Presumptive type Abeta afferents from the cornea terminated most prominently at the junction of the first cervical segment and the spinal trigeminal nucleus, pars caudalis. There was a second concentration of corneal terminations at the junction of pars caudalis and pars interpolaris of the spinal trigeminal nucleus. Sparse projections to the spinal trigeminal nucleus, pars oralis and the principal trigeminal nucleus were also detected. Presumptive type Abeta afferents from the eyelids terminated throughout the rostrocaudal extent of the spinal trigeminal nucleus with a heavy concentration within laminae III and IV of the first cervical segment. Central terminations from the frontal nerve were present in the principal trigeminal nucleus and throughout the spinal trigeminal nucleus, but were most prominent within the dorsal horn of the first cervical segment.
Specific binding of [ 125I Tyr0]BK was localized in the medulla oblongata to the regions of the nucleus of the solitary tract (NTS), area postrema (AP), dorsal motor nucleus of the vagus (X), and caudal subnucleus of the spinal trigeminal nucleus in both strains of rat.
the spinal trigeminal nucleus, (4). Furthermore, in the reticular formation and the spinal trigeminal nucleus, GAG67+ neurons tended to be distributed in the area where GLYT2+ neurons were sparse, and vice versa.
CONCLUSION: These findings suggest that cranial parasympathetic outflow contributes to migraine pain by activating or sensitizing (or both) intracranial nociceptors, and that these events induce parasympathetically independent allodynia by sensitizing the central nociceptive neurons in the spinal trigeminal nucleus..
Ineffective lesions involved A1 area, the nucleus gigantocellularis ventralis (NGCv), the spinal trigeminal nucleus and nucleus reticularis parvocellularis, the A5 area of the ventrolateral pons, the central gray and lateral mesencephalic tegmentum.
In situ hybridization using an NPFF2 riboprobe, and immunohistochemistry using a novel NPFF2 antibody, demonstrated strong NPFF2 expression in the superficial layer of the dorsal horn, and in the spinal trigeminal nucleus of the brainstem of the African green monkey (AGM).
On- and off-cells of the rostral ventromedial medulla and sensory neurons of the spinal trigeminal nucleus are extracellularly recorded by tungsten electrodes.
Of particular interest were UCN-immunoreactive inputs to the medial preoptic area, the paraventricular nucleus of the hypothalamus, the oral part of the spinal trigeminal nucleus, the flocculus of the cerebellum, and the spinal cord laminae VII and X.
Extracellular recordings were made from neurons in the subnucleus interpolaris and caudalis of the spinal trigeminal nucleus.
Survival intervals of 3 days were ideal for staining of hypoglossal neurons, whereas an interval of 4 days produced the strongest staining of synapses within the spinal trigeminal nucleus.
The highest densities were observed in lateral septal nucleus, median preoptic nucleus, dentate gyrus, amygdala, spinal trigeminal nucleus, mediovestibular nucleus, inferior cerebellar peduncles, and in most of cortical regions (0.81-1.4 fmol/mg tissue).
Noxious cutaneous mechanical stimulation significantly increased the proportions of neurons double-labelled for Fos and GABA(B) receptors in several brainstem regions, namely, the reticular formation of the caudal ventrolateral medulla (VLMlat and VLMrf), lateral reticular nucleus, spinal trigeminal nucleus, pars caudalis (Sp5C), nucleus of the solitary tract, dorsal reticular nucleus, ventral reticular nucleus, raphe obscurus nucleus and dorsal parabrachial nucleus (DPB).
In the medulla oblongata, immunoreactive cell bodies were observed in the laminar spinal trigeminal nucleus and in the lateral tegmental field; the dorsal motor nucleus of the vagus; the prepositus hypoglossal nucleus; the medial nucleus of the solitary tract; the rostral division of the cuneate nucleus, and close to the parvocellular division of the alaminar spinal trigeminal nucleus. The highest (moderate) density of immunoreactive fibres was observed in the periaqueductal grey; the parvocellular and magnocellular divisions of the alaminar spinal trigeminal nucleus; the laminar spinal trigeminal nucleus; the rostral division of the cuneate nucleus; the dorsal motor nucleus of the vagus; the lateral nucleus of the solitary tract, and in the midline between the central divisions of the reticulotegmental pontine nucleus.
In this anatomical tracing study we found that the vasodepressor part of the caudal midline medulla (CMM) receives inputs arising from spinal cord, spinal trigeminal nucleus (SpV) and nucleus of the solitary tract (NTS).
Sparse labelling was also found in the interpolar and caudal parts of the spinal trigeminal nucleus. The caudal parts of the spinal trigeminal nucleus, which has been demonstrated as a center of pain and temperature sensations of the head and face, transmits limited information from the STA to higher nervous centers..
In addition to the nuclei mentioned above, the highest densities of such immunoreactive fibers were located in the spinal trigeminal nucleus, the lateral reticular nucleus, the nucleus of the solitary tract, the superior colliculus, the substantia nigra, the nucleus ambiguus, the gracile nucleus, the cuneate nucleus, the motor hypoglossal nucleus, the medial and superior vestibular nuclei, the nucleus prepositus hypoglossi and the interpeduncular nucleus.
Nitric oxide is thought to control transmitter release and neuronal activity in the spinal dorsal horn and the spinal trigeminal nucleus, where nociceptive information from extra- and intracranial tissues is processed. Extracellular impulse activity was recorded from neurons in the rat spinal trigeminal nucleus with afferent input from the cranial dura mater. It is concluded that nitric oxide production contributes to the ongoing activity of sensitized neurons in the spinal trigeminal nucleus.
Immunofluorescence histochemical double-staining for preproenkephalin (PPE) and calbindin-D28k (CB), calretinin (CR) or parvalbumin (PV) were performed in the spinal trigeminal nucleus caudalis (Vc) of the rat.
We compared (in both magnitude and in their sensitivity to hexamethonium, 10 mg/kg, i.v.) the LBF responses evoked by electrical stimulation of various sites within the reflex arc (lingual nerve, trigeminal ganglion, spinal trigeminal nucleus (Vsp)) in type A and type B animals to examine where the suppressive effect of ear-bar insertion might be exerted (using artificially ventilated, cervically vago-sympathectomized cats deeply anesthetized with alpha-chloralose and urethane).
The range in latency differences suggests that some adjacent whisker responses arise within PrV itself, whereas others have a longer, multi-synaptic origin, possibly via the spinal trigeminal nucleus.
CONCLUSIONS: Based on current anatomofunctional knowledge and on the most recent pathogenetic findings, we believe that changes in hypothalamic activity posteroinferiorly may lead to activation of the caudal part of the spinal trigeminal nucleus by way of the hypothalamus, midbrain, and trigeminal nerve fibers and consequently to activation of the trigeminovascular system with a different location in the two syndromes.
Neither dose had any effects on the increases in CBF evoked by vibrissal stimulation in the principal sensory trigeminal nucleus and barrel cortex, but the higher dose statistically significantly enhanced the percent increases in CBF due to the sensory stimulation in the spinal trigeminal nucleus and VPM thalamic nucleus.
Glibenclamide tended to lower baseline CBF in almost all regions examined, statistically significantly (P<0.05) in the cerebellar lobules with all doses, in the cerebellar cortex with 10 micromol/l, in the pontine nuclei with 2 and 10 micromol/l, and in the spinal trigeminal nucleus of the unstimulated side with all doses. Vibrissal stimulation increased CBF unilaterally in all the stations of the pathway, but the percent increases were not statistically significantly affected by the glibenclamide treatment, except in the spinal trigeminal nucleus where it was reduced statistically significantly (P<0.05) only by 2 micromol/l glibenclamide.
These include the spinal trigeminal nucleus, area postrema, habenula, amygdala, and the cerebral cortex.
Significant activation was observed in the ipsilateral spinal trigeminal nucleus within the medulla and lower pons in response to at least one of the three facial stimuli in all applicable data sets.
In our results, NOS positive neurones and processes were seen in the spinal trigeminal nucleus, gracile nucleus, nucleus of the solitary tract, nucleus ambiguus, reticular nuclei and lateral to the pyramidal tract of the medulla.
In the mesencephalon, the periaqueductal grey, red nucleus and deep mesencephalic nucleus were strongly labelled, whereas, in the brainstem, the parabrachial nuclei, rostroventromedial medulla, nucleus tractus solitarius, spinal trigeminal nucleus, and the parvocellular, dorsal, lateral and ventral reticular nuclei were the most densely labelled regions.
A similar arrangement is found in the caudal spinal trigeminal nucleus.
This could influence the transmission of nociceptive input from primary afferents to secondary neurons in the spinal trigeminal nucleus and could be a contributing factor in the development of hyperalgesia after carrageenan injections or other chronic inflammatory conditions..
K41498 was subsequently radio-iodinated, and in autoradiographic studies, specific (sensitive to rat urocortin, astressin and aSvg30, but insensitive to antalarmin) binding of (125)I-K41498 (100 pM) was detected in the heart and in selected brain regions including the nucleus tractus solitarius (NTS), spinal trigeminal nucleus, lateral septum and around the anterior and middle cerebral arteries.
nitric oxide, is thus able to differentially influence afferent fibres in the superficial laminae of rat spinal trigeminal nucleus caudalis.
Calbindin-D28k (CB), calretinin (CR) and parvalbumin (PV) are the most commonly expressed calcium-binding proteins and are located abundantly in the medullary dorsal horn (also called the caudal subnucleus of the spinal trigeminal nucleus).
The results revealed that (1) a complicated relation existed between the nitrergic axon terminals and dendrites in the caudal part of the spinal trigeminal nucleus (cSTN); (2) the nitrergic neuronal cells bodies were not projection neurons, but rather, local circuit neurons; (3) although the thalamus projecting neurons in the cSTN did not synthesize NO, they could be modulated by NO diffused from nitrergic neurons; (4) c-fos positive neurons in the superficial laminae of the cSTN, detected following subcutaneous injection of 0.5 ml of 4% formalin into the left lateral face of the rats, respond to the release of glutamate through activation of N-methyl-D-aspartate (NMDA), alpha-amine-3-hydroxy-5-methyl-4-isoxazole-propionate (AMPA) and metabotropic glutamate (mGlu) receptors expressed by these c-fos neurons; and (5) NO might play a seemingly less important role than glutamate in neural transmission..
Data showed specific binding sites for B2 receptor (0.4-1.5 fmol/mg tissue) in 11 medullary nuclei from 4 control specimens (paratrigeminal > ambiguus > cuneate, gelatinous layer of the caudal spinal trigeminal nucleus > caudal and interpolar spinal trigeminal, external cuneate, solitary tract > hypoglossal > gracile > inferior olivary nuclei).
Nucleus tractus solitarius, C3 catecholamine region, rostral ventrolateral medulla and spinal trigeminal nucleus provide indirect inputs.We propose that the SCN receives feedback primarily from interoceptive systems such as the circumventricular, autonomic, and neuroendocrine systems that are important in the central regulation of glucose metabolism (e.g., insulin and glucocorticoids)..
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