Mesencephalic Trigeminal Nucleus


Heavy P2X(5) receptor immunostaining was observed in the mitral cells of the olfactory bulb; cerebral cortex; globus pallidum, anterior cortical amygdaloid nucleus, amygdalohippocampal area of subcortical telencephalon; anterior nuclei, anteroventral nucleus, ventrolateral nucleus of thalamus; supraoptic nucleus, ventromedial nucleus, arcuate nucleus of hypothalamus; substantia nigra of midbrain; pontine nuclei, mesencephalic trigeminal nucleus, motor trigeminal nucleus, ambiguous nucleus, inferior olive, hypoglossal nucleus, dorsal motor vagus nucleus, area postrema of hindbrain; Purkinje cells of cerebellum; and spinal cord.  

In the postnatal CNS, alpha-taxilin expression was almost confined to the neuronal lineage, with the highest levels of expression in motor neurons within the brainstem nuclei and spinal cord and in primary sensory neurons in mesencephalic trigeminal nucleus.  

The present study was undertaken to examine the distribution of HO-2 and NOS of the trigeminal primary afferent neurons of the rat, located in the trigeminal ganglion (TG) and mesencephalic trigeminal nucleus (MTN), using histochemistry and immunohistochemistry.  

Using bioluminescence imaging of brain tissue explants from transgenic mice containing the firefly luciferase gene luc controlled by the mPer1 promoter, we discovered elevated transgene expression throughout the mesencephalic trigeminal nucleus (Me5) of the brain stem.  

The mesencephalic trigeminal nucleus (MesV) contains the somata of primary afferent neurons that innervate muscle spindles in masticatory muscles and mechanoreceptors in the periodontal ligaments.  

Dynorphin-A-like immunoreactivity was investigated in the rat mesencephalic trigeminal nucleus (Mes 5) at the light and electron microscopic levels.  

In the other parts of the brainstem, vestibular terminals were detected in the termination areas of the mesencephalic trigeminal nucleus and of the Gasserian (Vth) ganglion and they were probably involved in polysynaptic connections.  

Primary sensory fibers innervating the head region derive from neurons of both the trigeminal ganglion (TG) and mesencephalic trigeminal nucleus (MTN).  

The mesencephalic trigeminal nucleus (Me5) innervates muscle spindles and is responsible for receiving and transmitting proprioception from the oro-facial region.  

The labeling in the individual nuclei was bilateral with an ipsilateral predominance to each injection site, with the exception of the mesencephalic trigeminal nucleus, where the labeling was ipsilateral to the injection site in the JC nucleus.  

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.  

Here we show a potential role of I(NaP) in spike initiation of primary sensory neurons in the mesencephalic trigeminal nucleus (MTN) that display a backpropagation of the spike initiated in the stem axon toward the soma in response to soma depolarization.  

The neuronal labeling was high in the neocortex, striatum, hippocampus, brain stem nuclei, deep cerebellar nuclei, catecholaminergic neurons, and reticular nuclei, and particularly high in neurons of the mesencephalic trigeminal nucleus and medial habenular nucleus.  

The CaM mRNA levels were low to moderate, without significant differences, in the mesencephalic trigeminal nucleus.  

Masseter muscle-spindle responses to ramp-and-hold jaw stretches were recorded from the mesencephalic trigeminal nucleus in 35 barbiturate-anesthetized female Wistar rats.  

Recently, we demonstrated that the mesencephalic trigeminal nucleus (Me5) is involved in the control of feeding and exploratory behavior in mice without modulating the emotional state [ Ishii, T., Furuoka, H., Itou, T., Kitamura, N., and Nishimura, M.  

Its increased stretching may induce involuntary contraction of the ipsilateral occipitofrontalis muscle via the mesencephalic trigeminal nucleus and the facial subnucleus as another stretch reflex.  

Double labelling of biotinylated dextran amine (BDA) tracing and cholera toxin B (CTB) transport demonstrated that labelled axons and terminals from the mesencephalic trigeminal nucleus (Vme) overlapped with XII premotor neurons in the alpha division and in PCRt, IRt, Vodm and Vidm.  

The perikarya of sensory neurons of the mesencephalic trigeminal nucleus (MTN) receive dense histaminergic hypothalamic innervation.  

The present investigation was undertaken to map the distribution pattern of the enzyme responsible for the synthesis of NO, nitric oxide synthase (NOS), and especially its neuronal isoform (nNOS) in the population of primary afferent neurons of the trigeminal ganglion (TG) and mesencephalic trigeminal nucleus (MTN) of the rabbit.  

Retrograde tract-tracing with FB also showed that the mesencephalic trigeminal nucleus sends neural pathways towards the ipsilateral PSTN, with outputs from cranial and caudal aspects of the brainstem.  

Among primary sensory neurons, those in the mesencephalic trigeminal nucleus (MTN) are exceptional in their ability to initiate soma spikes (S-spikes) in response to synaptic inputs, consequently displaying two kinds of S-spikes, one caused by invasion of an axonal spike arising from the sensory receptor and the other initiated by somatic inputs.  

To determine the relative importance of tyrosine kinase receptors on the survival of axotomized trigeminal nuclear neurons, we examined the temporal expression profile of tyrosine kinase A, tyrosine kinase B and tyrosine kinase C receptors in the mesencephalic trigeminal nucleus and the motor trigeminal nucleus following transection of the masseteric nerve in rats. We found increase in tyrosine kinase A-immunoreactive mesencephalic trigeminal nucleus neurons in the second week after axotomy but no change in the number of tyrosine kinase A-immunoreactive motor trigeminal nucleus neurons. There was no change in the number of tyrosine kinase B-immunoreactive mesencephalic trigeminal nucleus neurons but the significant increase of tyrosine kinase B-immunoreactive motor trigeminal nucleus neurons throughout the period of observation (3 weeks) peaked at approximately 1 week after axotomy. There was no alteration in the number of tyrosine kinase C-immunoreactive mesencephalic trigeminal nucleus neurons but significant increase in tyrosine kinase C-immunoreactive motor trigeminal nucleus neurons observable by 4 days post-axotomy was followed by decline to levels lower than the control in 2 weeks. Temporal changes in the expression of individual tyrosine kinase receptors in mesencephalic trigeminal nucleus and motor trigeminal nucleus neurons following transection of the masseteric nerve suggest differential contribution of tyrosine kinase-specific neurotrophins to the survival of these neurons after axotomy..  

Trigeminal proprioceptive muscle afferent neurons situated within the brainstem in the mesencephalic trigeminal nucleus did not express CGRP or SP prior to or following inflammation.  

They are not proprioceptors because they fail two other tests: ASIC3+ cells do not express parvalbumin and they are absent from the mesencephalic trigeminal nucleus.  

Tracer application into the cervical spinal cord, combined with CB immunohistochemistry, resulted in retrogradely labeled cells throughout the brain, five groups of which showed CB immunoreactivity: (1) the mesencephalic trigeminal nucleus, (2) the laterodorsal tegmental nucleus, (3) the raphe nucleus, (4) the middle reticular nucleus and (5) the inferior reticular nucleus.  

Double labeling of anterograde tracing combined to retrograde transport was performed by injection of biotinylated dextran amine into the mesencephalic trigeminal nucleus and cholera toxin B subunit or horseradish peroxidase into the vagus nerve and the recurrent laryngeal nerve. mesencephalic trigeminal nucleus neuronal terminals contacted with visceral and laryngeal muscle motoneurons in the ambiguus nucleus and the nearby intermediate reticular zone. By electron microscopic observation, we confirmed that mesencephalic trigeminal nucleus terminals made asymmetric axodendritic synapses with these motoneurons.  

In order to determine whether the mesencephalic trigeminal neurons may receive a direct hypothalamic orexinergic input, the distribution of orexin A immunoreactivity was examined in the rat mesencephalic trigeminal nucleus (MTN), using orexin A immunohistochemistry.  

Addicsin transcripts were also extremely abundant in trigeminal neurons such as the principal trigeminal nucleus, mesencephalic trigeminal nucleus and motor trigeminal nucleus.  

Co-expression of MIZIP and MCHR1 was observed, for example, in pyramidal neurons of the cerebral cortex and hippocampus, in neurons of the olivary nucleus, lateral hypothalamus, nucleus accumbens, caudate putamen, pontine, and mesencephalic trigeminal nucleus.  

The mesencephalic trigeminal nucleus (Me5), which receives input from oral proprioceptors and projects to higher brain regions, is involved in mastication-induced modulation of satiation.  

To identify the NOS-containing structures of rat trigeminal primary afferent neurons, located in the trigeminal ganglion (TrG) and mesencephalic trigeminal nucleus (MTN), histochemistry to its selective marker nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) was applied in this study.  

The mesencephalic trigeminal nucleus (MesV) contains the somata of primary afferent neurons innervating masticatory muscle spindles and the periodontal membrane.  

Labelled sensory first-order neurons were found in the ipsilateral trigeminal ganglion (TG) and in the ipsilateral mesencephalic trigeminal nucleus (MTN).  

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.  

In addition, strong hybridization signals were localized in various nuclei: main and accessory olfactory bulb, compact part of the substantia nigra, pontine gray matter, tegmental reticular nucleus, Edinger-Westphal nucleus, trigeminal motor nucleus, locus coeruleus, mesencephalic trigeminal nucleus, raphe nuclei, facial nucleus, ambiguus nucleus, dorsal motor vagal nucleus, and inferior olivary 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).  

Labeled cells were observed in the mesencephalic trigeminal nucleus and the trigeminal motor nucleus.  

Among neurons, the primary sensory neurons of the mesencephalic trigeminal nucleus appeared to be those that most strongly express SNAT2, but many other neurons, including cortical pyramidal cells and their dendrites were also intensely stained.  

In the mesencephalic trigeminal nucleus, Cx26, 32, and 43 expression was intense throughout development, with only Cx36 showing a developmental regulation.  

During development of the chick central nervous system, the trajectories of the descending medial and lateral longitudinal fascicles (MLF and LLF) are pioneered by axons originating from the interstitial nucleus of Cajal (INC) and the mesencephalic trigeminal nucleus (MTN), respectively.  

The normal development of the mesencephalic trigeminal nucleus (MesV) of the white Peking duck (Anas platyrhynchos) was studied from the 9th day of incubation until hatching and during adulthood.  

We identified eGFP-containing cells in specific areas of the brain, including cerebellum, hippocampus, dorsal motor nucleus of the vagus, inferior olivary nucleus, reticular formation, rostral ventrolateral medulla, central nucleus of the amygdala, lateral parabrachial nucleus, mesencephalic trigeminal nucleus, bed nucleus of stria terminalis, and subfornical organ.  

The p55TNFR gene was constitutively expressed in many neurons with high levels in brainstem motor nuclei and in neurons of the sensory mesencephalic trigeminal nucleus.  

NT-4 immunoreactivity was strong in large neurons of the red nucleus and pontine reticular nucleus as well as the locus coeruleus, and moderate in cells in the mesencephalic trigeminal nucleus and interstitial nucleus of the medial longitudinal fasciculus.  

The MMR was evoked by electrical stimulation of the mesencephalic trigeminal nucleus.  

Effective stretching of the mechanoreceptor in the proximal part of Müller's muscle by voluntary phasic contraction of the levator muscle for initial opening of the eye induces involuntary tonic contraction of the levator muscle as a stretch reflex via the mesencephalic trigeminal nucleus, to maintain an adequate visual field.  

The developing mesencephalic trigeminal nucleus (nucleus of the fifth cranial nerve; Mes5) is composed of four neuron populations: 1) the medial group, located at the tectal commissure; 2) the lateral group distributed along the optic tectum hemispheres; 3) a group outside the neural tube; and 4) a population located at the posterior commissure.  

The responses of single MSAs to trapezoidal displacement of the mandible were recorded from the mesencephalic trigeminal nucleus.  

After application of the tracers to the trigeminal nerve, elicited dye-coupled neurons located mainly in the termination area of the descending limb of the mesencephalic trigeminal nucleus.  

During the prometamorphic period, spinal projections arise in the nucleus of the solitary tract, the lateral line nucleus, and the mesencephalic trigeminal nucleus.  

CONCLUSIONS: The Mueller muscle can be thought of as a large, serial kind of muscle spindle, so that stretching by voluntary phasic contraction of the levator muscle for initial eye opening may evoke an afferent impulse to the mesencephalic trigeminal nucleus.  

Most of their cell bodies are located in the trigeminal ganglion (TG) but part of them lie in the mesencephalic trigeminal nucleus (MTN).  

At E14.5, the optic tract and retina, nucleus tractus solitarius, mesencephalic trigeminal nucleus, and sensory nerves in both respiratory and digestive tract showed positive staining. P2X(3) immunoreactivity in the facial nucleus, spinal trigeminal tract, the mesencephalic trigeminal nucleus, and the vestibular nucleus were undetectable in postnatal day 16 rat brainstem.  

The cells of the mesencephalic trigeminal nucleus (MTN) are the proprioceptive sensory neurons that innervate the jaw muscles.  

Furthermore, the FMR preceding the force onset disappeared after making a lesion of the mesencephalic trigeminal nucleus (MesV) where the ganglion cells of the muscle spindle afferents from the jaw-closing muscles are located.  

We examined immunoreactivities for gamma-aminobutyric acidB-receptor (GABA(B)R) subtypes, GABA(B)R1 and GABA(B)R2, in the mesencephalic trigeminal nucleus neurons (MTN neurons) of the rat.  

A direct projection from rat mesencephalic trigeminal nucleus (Vme) neurons to the hypoglossal nucleus (XII) motoneurons was studied using a double labeling method of anterogradely biotinylated dextran amine (BDA) tracing combined with retrogradely horseradish peroxidase (HRP) transport at both light and electron microscopic levels.  

However, we could not detect KCC2 messenger RNA expression in the dorsal root ganglion and mesencephalic trigeminal nucleus, where primary sensory neurons show depolarizing responses to GABA, suggesting that the absence of KCC2 is necessary for this phenomenon.  

Two days later, 1-5 jaw-muscle spindle afferent axons located in the mesencephalic trigeminal nucleus were physiologically identified and intracellularly stained with biotinamide.  

In general, the immunoreactivity was observed both in the cytoplasm and cellular nucleus, although the immunoreactivity was not found in the cellular nucleus in some large neurons such as in the mesencephalic trigeminal nucleus, lateral vestibular nucleus or gigant cellular reticular formation.  

Moderate levels of Y1 immunoreactivity were found the in the main olfactory bulb, dorsomedial part of suprachiasmatic nucleus, paraventricular hypothalamic nucleus, ventral nucleus of lateral lemniscus, pontine nuclei, mesencephalic trigeminal nucleus, external cuneate nucleus, area postrema, and nucleus tractus solitarius.  

The purpose of the present study was to obtain reliable evidence for the presence of gamma-aminobutyric acid-ergic (GABAergic) synapses upon mesencephalic trigeminal nucleus (MTN) neurons in the rat.  

Staining was also observed in the gracile nucleus, the mesencephalic trigeminal nucleus, and the central pontine gray.  

In the brainstem, Y5 immunoreactivity was most intense in the Edinger-Westphal nucleus, locus coeruleus and the mesencephalic trigeminal nucleus.The present study provides neuroanatomical evidence for the possible sites of action of the neuropeptide Y/Y5 receptor system in the control of cortical/limbic function.  

Neurons of the mesencephalic trigeminal nucleus (MTN) are considered to be homologous to mechanosensitive neurons in the sensory ganglia.  

Although the staining intensity was relatively low compared to that of the forebrain, moderate alpha(1B)-IR was found in the dorsal cochlear nucleus and mesencephalic trigeminal nucleus.  

Giant reticular cells and large neurons in the mesencephalic trigeminal nucleus were immunoreactive for p75 and all trk receptors.  

In situ hybridization demonstrated that NB-3 mRNA was preferentially expressed in the accessory olfactory bulb, layers II/III and V of the cerebral cortex, piriform cortex, anterior thalamic nuclei, locus coeruleus of the pons and mesencephalic trigeminal nucleus, and in Purkinje cells of the cerebellum.  

By stage 13, RXR gamma transcripts accumulate to detectable levels along the midline of the posterior optic tectum, where the neural crest-derived sensory neurons of the mesencephalic trigeminal nucleus are located.  

Peripheral innervation patterns of proprioceptive afferents from dorsal root ganglia and the mesencephalic trigeminal nucleus were assessed in trkC-deficient mice using immunohistochemistry for protein gene product 9.5 and parvalbumin. In these same animals, however, proprioceptive afferents from mesencephalic trigeminal nucleus innervated masseter muscles and formed primary endings of muscle spindles.  

Simultaneous records were made of the discharges of muscle spindle units in the mesencephalic trigeminal nucleus, masseter and digastric muscle activity (electromyogram [ EMG]), and jaw-movement parameters during cortically induced rhythmic jaw movements.  

These results indicate that some orofacial proprioceptive feedback transmitted via the mesencephalic trigeminal nucleus reaches the cervical spinal cord directly and suggests that jaw-muscle spindle afferent feedback reaches the cervical spinal cord predominately via relays in the dorsomedial part of the spinal trigeminal subnucleus oralis and the parvicellular reticular formation.  

At postnatal day 0 (PND 0), neurotrophins expression was virtually absent from all auditory nuclei in the brainstem, even though some positive neurons were observed in the mesencephalic trigeminal nucleus at this age.  

Phosphorylase kinase immunoreactivity could not be detected in neurons, with the exception of a group of large neurons in the brain stem, most likely belonging to the mesencephalic trigeminal nucleus.  

The primary sensory trigeminal system in birds comprises the mesencephalic trigeminal nucleus and the trigeminal ganglion with projections to the principal sensory nucleus (PrV) and the descending tract with its subnuclei.  

To explore the response characteristics of muscle spindle units in the masticatory muscles in the rabbit, the responses of muscle spindle units were recorded from the mesencephalic trigeminal nucleus (MesV) under halothane anesthesia during ramp-and-hold stretches.  

Projections from the mesencephalic trigeminal nucleus to the vestibular nuclei were analyzed using retrograde and anterograde tracing methods.  

Somatodendritic labelling was particularly obvious in the olfactory bulb, cerebral cortex, hippocampal formation, mesencephalic trigeminal nucleus and cerebellum, as well as in cranial and spinal motor areas.  

An extensive expression pattern was observed, including: olfactory bulb, cerebral cortex, hippocampus, habenula, thalamic and subthalamic nuclei, caudate putamen, posteromedial amygdalo-hippocampal and amygdalo-cortical nuclei, substantia nigra pars compacta, ventromedial and arcuate hypothalamic nuclei, supraoptic nucleus, tuberomammillary nucleus, mesencephalic trigeminal nucleus, dorsal raphe, locus coeruleus, medial parabrachial nucleus, tegmental areas, pontine nuclei, red nucleus, lateral superior olive, cochlear nuclei, spinal trigeminal nuclei, cranial motor nuclei, ventrolateral medulla, area postrema, nucleus of solitary tract, and cerebellar cortex.  

The mesencephalic trigeminal nucleus is composed of large (35-50 microns) pseudo-unipolar neurons. This study demonstrates that the pseudo-unipolar neurons of the mesencephalic trigeminal nucleus express AMPA glutamate receptor subunits, which indicates that these neurons receive glutamatergic input. With GluR1 antibody only the smallest multipolar neurons were recognized as immunopositive within the mesencephalic trigeminal nucleus. In addition the former antibody stained small multipolar neurons within the mesencephalic trigeminal nucleus, though with somewhat larger dimensions than those immunoreactive for GluR1. Furthermore, a considerable number of microglial cells within and surrounding the mesencephalic trigeminal nucleus displayed very intense immunoreactivity for GluR4.  

The trigeminal ganglion (TrG) and mesencephalic trigeminal nucleus (MTN) neurons are involved in the transmission of orofacial sensory information.  

However, both beta-gal activity as identified by X-gal, and HAGT mRNA as detected by in situ hybridization, were also found in neurons in restricted areas of the brain, including the mesencephalic trigeminal nucleus (meV), subfornical organ (SFO) and the external lateral parabrachial nucleus (elPB).  

When PHA-L was injected to dorsomedial part of the subnucleus oralis of the spinal trigeminal nucleus (Vodm), anterogradely labeled varicosities and boutons were observed in the mesencephalic trigeminal nucleus (Vme).  

In addition, the amplitude of the masseteric monosynaptic reflex elicited by electrical stimulation of the mesencephalic trigeminal nucleus showed no significant change in association with the altered respiratory mode.  

In addition, neurons in the sensory nuclei, such as the mesencephalic trigeminal nucleus and the nucleus ambiguus, and many cortical neurons are TBP-1 mRNA positive.  

The most prominent expression in rat was observed in neurons of the mitral cell layer of the olfactory bulb, red nucleus, mesencephalic trigeminal nucleus, motor trigeminal nucleus, facial nucleus, reticular nucleus and Purkinje cell layer.  

Additional novel localizations of putative cholinergic terminals to the subependymal zone surrounding the lateral ventricles, and putative cholinergic cell bodies in the sensory mesencephalic trigeminal nucleus, a primary sensory afferent ganglion located in the brainstem, are documented here. The cholinergic phenotype of neurons of the sensory mesencephalic trigeminal nucleus was confirmed by choline acetyltransferase immunohistochemistry.  

Pons: label was detected in the neuropil of the periventricular gray, concentrated in the dorsal- and external-lateral subnuclei of lateral parabrachial nucleus, and present intracellularly in the mesencephalic trigeminal nucleus.  

While 5-HT1B receptor messenger RNA was abundant throughout the brain (with highest levels in the striatum, nucleus accumbens, olfactory tubercle, cortex, hypothalamus, hippocampal formation, amygdala, thalamus, dorsal raphe and cerebellum), 5-HT1D receptor messenger RNA exhibited a more restricted pattern; it was found mainly in the olfactory tubercle, entorhinal cortex, dorsal raphe, cerebellum, mesencephalic trigeminal nucleus and in the trigeminal ganglion.  

In addition, the Purkinje cells of the cerebellar cortex, the nerve cells in the mesencephalic trigeminal nucleus, and the magnocellular neurons of the supraoptic and paraventricular hypothalamic nuclei showed weak immunoreactivity.  

The rat mesencephalic trigeminal nucleus (MTN) receives a dopaminergic innervation.  

BACKGROUND: The present study deals with the possibility that the mesencephalic trigeminal nucleus (MeV) neurons that innervate the muscle spindles of the jaw closing muscles may also have collaterals projecting to the cervical spinal cord.  

The mesencephalic trigeminal nucleus contains cell bodies of primary somatic sensory neurons that innervate the head region.  

The ontogenetic development and cell differentiation of the mesencephalic trigeminal nucleus (Ntm) is lightmicroscopically examined in 58 bovine embryos and fetuses ranging from 2.4 to 80 cm Crown-Rump-Length (CRL).  

Microelectrodes filled with either horseradish peroxidase (HRP) or biotinamide (Neurobiotin) were advanced into the mesencephalic trigeminal nucleus (Vme) in anesthetized rats.  

In the present study, PACAP expression in the mesencephalic trigeminal nucleus of the rat was examined after transsection of the main trunk of the masseteric nerve.  

Discharges of jaw muscle spindles were recorded during chewing carrot from mesencephalic trigeminal nucleus (Mes V) in the awake rabbit to evaluate contribution of the muscle spindles to the development of complete sequences of masticatory movements.  

A transient spinal projection from an unknown group of neurons located immediately lateral to and partly intermingled with the mesencephalic trigeminal nucleus arrived in the lumbosacral spinal cord at E18 and had disappeared at P1. This cell group, called Gr?, closely resembled the mesencephalic trigeminal nucleus (Me5).  

Smaller mercury deposits were found in the brain stem (in the mesencephalic trigeminal nucleus, noradrenergic neurons, and in neurons for extraocular muscles), the cerebellum (in the dentate nucleus) and in lateral motor neurons in the C2/3 spinal cord.  

Evidence is presented, based on immunoblotting, immunohistochemistry and double immunolabelling procedures, for the existence of hyaluronan receptor immunoreactivity in discrete nerve cell populations of the rat brain, present within the zona compacta and the zona reticulata of the substantia nigra, the ventral tegmental area the locus coeruleus, the mesencephalic trigeminal nucleus, the nucleus of the trapezoid body, the motor trigeminal nucleus and the lateral cerebellar nucleus. In all the nerve cells, the immunoreactivity had the appearance of punctate bodies mainly located in the cytoplasm of the perikarya of the above nerve cell populations as also shown by confocal laser microscopy in the mesencephalic trigeminal nucleus.  

Combined retrograde neuronal tracing with FluoroGold (FG) and a double immunofluorescence method was performed to examine the effects of peripheral nerve injury of the masseteric nerve (MassN) on the levels of two calcium binding proteins (CaBPs), parvalbumin (PV) and calbindin D28k (CB), and neuropeptide Y (NPY) in the mesencephalic trigeminal nucleus (MesV) in the rat.  

After injection of the fluorescent retrograde tracer, tetramethylrhodamine dextran amine (TRDA), into the Vm unilaterally, neurons labeled with TRDA were seen ipsilaterally in the mesencephalic trigeminal nucleus, and bilaterally in the parabrachial region, the supratrigeminal and intertrigeminal regions, the reticular formation just medial to the Vm, the principal sensory and spinal trigeminal nuclei, the pontine and medullary reticular formation, especially the parvicellular part of the medullary reticular formation, the alpha part of the gigantocellular reticular nucleus, and the medullary raphe nuclei.  

Finally, the mesencephalic trigeminal nucleus and tract labeled in some cases and may have local glutamatergic connections..  

The mesencephalic trigeminal nucleus (Vme) neurons are primary sensory neurons transmitting orofacial proprioceptive sensation.  

Several of the glycogen-positive cell groups such as the mesencephalic trigeminal nucleus and the brainstem somatic and special visceral efferent nuclei have been previously detected in the developing brain of small, common laboratory mammals.  

Electron-dense granular reaction product of peroxidase activity was observed in astrocytes of all brain regions examined (cerebral cortex, striatum, cerebellar cortex, hippocampal formation, corpus callosum, mesencephalic trigeminal nucleus). Neurons (with the exception of neurons of the mesencephalic trigeminal nucleus), their processes, and their synaptic endings were free of reaction product.  

In studies using immunocytochemicalretrograde tracing techniques, some classical neurotramsitters mediating the afferent modulation of the mesencephalic trigeminal nucleus (MTN) have been investigated.  

At postnatal day 0, TrkB and TrkC staining was virtually absent from auditory nuclei, although immunopositive neurons were present in the mesencephalic trigeminal nucleus.  

mesencephalic trigeminal nucleus (Me5) neurons are unique in that they are derived from the neural crest like other neurons in the peripheral nervous system, but enter secondarily into the central nervous system.  

Spindle afferent boutons closely apposed another 10 mesencephalic trigeminal nucleus (Vme) perikarya labeled from the jaw muscles.  

The first S-100 beta containing neurons were seen in the mesencephalic trigeminal nucleus at postnatal day 1 (P1), and in the motor trigeminal nucleus at P3.  

The ultrastructure and synaptic organization of the mesencephalic trigeminal nucleus (MTN) were studied in adult cats by transmission electron microscopy and more precisely quantified with an automated image analysis system.  

With the use of postembedding electron-microscopic immunogold cytochemistry, the vesicular distribution of serotonin within serotonergic synaptic terminals in the mesencephalic trigeminal nucleus was determined in order to obtain further insight into the mechanisms and functional significance of serotonin release to these jaw muscle spindle afferent neurons.  

Projections from the pars caudalis (Vc) of Vsp and the mesencephalic trigeminal nucleus (Vmes) are absent.  

mesencephalic trigeminal nucleus), or in axonal projections (e.g.  

Similarly PMO-II only develops around PN5, first in the dorsal and caudal linear raphe and later on (at PN7) also in the pontine nucleus and in the median raphe; at PN10 PMO-II gradually had vanished from these areas and strongly developed in the dorsal raphe and in the mesencephalic trigeminal nucleus.  

Finally PMO-VI is mainly present in the oriens layer and in the stratum radiatum of the hippocampus formation, in the supraoptic and lateral magnocellular nucleus of the hypothalamus, in the mesencephalic trigeminal nucleus, in the ventral auditory nucleus and in the facial nucleus of the brain stem as well as in red nucleus of the reticular formation and in the Purkinje layer of the cerebellar cortex.  

Histamine neurons in the mesencephalic trigeminal nucleus (Me5) regulated masticatory functions, particularly eating speed, and those in the VMH controlled intake volume at meals.  

Histamine neurons in the mesencephalic trigeminal nucleus (Me5) were involved in regulation of masticatory functions, particularly eating speed, while histamine-containing neurons in the VMH controlled intake volume of meals.  

(3) Mastication activated afferent signal transmission from proprioceptors in the oral cavity to the mesencephalic trigeminal nucleus(Me5).  

It is expressed in: (1) motor nuclei such as the oculomotor nucleus, trochlear nucleus, motor trigeminal nucleus, abducens nucleus, facial nucleus, ambiguus nucleus, dorsal motor nucleus of vagus and hypoglossal nucleus; (2) several sensory-related nuclei like the mesencephalic trigeminal nucleus, ventral nucleus of the lateral lemniscus, lateral and spinal vestibular nuclei, ventral and dorsal cochlear nuclei and nucleus of the trapezoid body; and (3) other regions such as the red nucleus, dorsal raphe nucleus, pontine nuclei, three cerebellar nuclei (medial, interposed and lateral), Purkinje cells, cells in the granular layer of the cerebellum, locus coeruleus, several areas of the reticular nucleus and area postrema..  

Intracellular recordings in the mesencephalic trigeminal nucleus (Vme) were identified as spindle afferent responses by their increased firing during stretching of the jaw-elevator muscles.  

Labeled neuronal perikarya in the CNS are uncommon and localized to the mesencephalic trigeminal nucleus.  

It was found that the premotor neurons distributed in the mesencephalic trigeminal nucleus, medial part of the parabrachial region, supratrigeminal region, and dorsal parts of the principal sensory, oral spinal and interpolar spinal trigeminal nuclei project preferentially to the dorsolateral division of the trigeminal motor nucleus, whereas those in the lateral part of the parabrachial region, intermediate parts of the principal sensory, oral spinal and interpolar spinal trigeminal nuclei, and alpha part of the gigantocellular reticular nucleus project preferentially to the ventromedial division of the trigeminal motor nucleus.  

BACKGROUND: Recent studies conducted on the rat have demonstrated that the mesencephalic trigeminal nucleus (MTN) neurons, involved in the proprioceptive transmission, contain some neuroactive substances, including classical and amino acid neurotransmitters.  

The distribution of calcitonin gene-related peptide (CGRP)- and neuropeptide Y (NPY)-like immunoreactivity (LI) in the cat trigeminal ganglion (TrG) and mesencephalic trigeminal nucleus (MTN) was studied by the indirect immunofluorescent technique and unlabelled peroxidase-antiperoxidase method.  

The intracellular responses of periodontal afferents in the mesencephalic trigeminal nucleus, Su5 interneurones and jaw-closing motor neurones were studied in response to graded, single-shock stimulation of the ipsilateral inferior alveolar nerve.  

Among 11 different neuron types, nearly a two-fold range of histochemical staining intensities was observed, with the darkest staining in neurons of the mesencephalic trigeminal nucleus.  

Control injections of cholera-toxin B were made in areas surrounding the locus coeruleus, including (1) Barrington's nucleus, (2) the mesencephalic trigeminal nucleus, (3) a previously undefined area immediately rostral to the locus coeruleus and medial to the mesencephalic trigeminal nucleus that we named the peri-mesencephalic trigeminal nucleus, and (4) the medial vestibular nucleus lateral to the caudal tip of the locus coeruleus.  

Axon collaterals and boutons from jaw-muscle spindle afferents were found in Vmo; Vsup; the dorsomedial part of the trigeminal principal sensory nucleus (Vpdm); the dorsomedial part of the spinal trigeminal subnuclei oralis, interpolaris (Vidm) and caudalis; the parvicellular reticular formation (PCRt); and the mesencephalic trigeminal nucleus.  

Confocal microscopy of rat brain sections double-labelled with anti-mu opioid receptor and anti-GIRK1 antibodies revealed colocalization of GIRK1 and mu opioid receptor immunoreactivities in somata of subpopulations of neurons in the cerebral cortex, anterior olfactory nucleus, nucleus accumbens, globus pallidus, substantia nigra, peripeduncular nucleus, hippocampal formation, diagonal band, thalamus, locus coeruleus, dorsal raphe, red nucleus, nucleus of the trapezoid body, reticular nucleus, vestibular nucleus, inferior colliculus and the mesencephalic trigeminal nucleus.  

BACKGROUND: It is well known that the mesencephalic trigeminal nucleus (MTN) neurons transmit somatosensory information from proprioceptors in the oral-facial region.  

No immunoreactivity was observed in the subnucleus interpolaris, subnucleus oralis spinal trigeminal nucleus complex (STNC), principal trigeminal nucleus and mesencephalic trigeminal nucleus of the experimental rats and all the trigeminal nuclei of control animals.  

Immunoreactivity was only present in the somatic neurons of the mesencephalic trigeminal nucleus in the brain stem and in dorsal root ganglia (DRG), but not in the autonomic neurons of the superior cervical ganglia or in the sensory nuclei of the spinal cord.  

IRS-1 immunostaining was very weak or totally absent in neurons of the olfactory bulb, the supraoptic and paraventricular nuclei, the mesencephalic trigeminal nucleus, and the granule cell layer of the cerebellum, despite the fact that these areas were immunolabeled with antibodies against insulin or IGF-I receptors and/or PI-3 kinase.  

IL-1R1 mRNA was expressed in several brain regions including the anterior olfactory nucleus, medial thalamic nucleus, posterior thalamic nucleus, basolateral amygdaloid nucleus, ventromedial hypothalamic nucleus, arcuate nucleus, median eminence, mesencephalic trigeminal nucleus, motor trigeminal nucleus, facial nucleus and Purkinje cells of the cerebellum.  

The animals were perfused at 0, 1, 2, 4, 8, 12 and 24 h thereafter, and the brains containing the mesencephalic trigeminal nucleus and the spinal trigeminal nucleus complex were then removed. The subnucleus interporalis and the subnucleus oralis of the spinal trigeminal nucleus complex, the principal trigeminal nucleus and the mesencephalic trigeminal nucleus of the experimental animals and all the trigeminal nuclei of the control animals contained no immunopositive cells.  

The cobalt tracing technique was used to study synaptic relations of trigeminal motoneurons and the axon terminals of the mesencephalic trigeminal nucleus (Vmes) in a frog (Rana esculenta).  

By in situ hybridization and immunohistochemistry, we examined the expression of neuropeptides such as neuropeptide Y (NPY), galanin (Gal), substance P (SP), vasoactive intestinal polypeptide (VIP) and their mRNAs in the rat mesencephalic trigeminal nucleus (Mes5) following masseteric nerve transection.  

Within the trigeminal ganglion of normal subjects, numerous fibers and most of the neuronal cell bodies showed NGFr(p75)-IR that varied in intensity, while cells and fibers with NGFr(p75)-IR were less numerous within the mesencephalic trigeminal nucleus.  

Further caudally, neurons with different staining intensities were found in the lateral hypothalamic area, lateral mammillary nucleus, periventricular organ, ventral tegmental area, medial spiriform nucleus, optic tectum, isthmooptic nucleus, mesencephalic trigeminal nucleus, interpeduncular nucleus, and central gray of the mesencephalon.  

Trigger pulses were derived from spindle afferent cell bodies of the jaw-closer muscles recorded in the mesencephalic trigeminal nucleus, and characterized by the effect of SCh on their responses to ramp-and-hold stretches.  

Muscle spindle afferents recorded in the mesencephalic trigeminal nucleus were categorised as primary or secondary by their responses to succinylcholine during sinusoidal or ramp-and-hold stretches.  

The mesencephalic trigeminal nucleus (MesV) of Rana ridibunda is formed by a population of 100 to 125 unipolar or multipolar cells that are scattered on both sides of the rostral mesencephalic tectum.  

Apart from loss of dorsal root ganglion cells, severe loss of secondary sensory neurons was observed, including the nucleus dorsalis in the spinal cord, the spinal and principal trigeminal nuclei and, in particular, the mesencephalic trigeminal nucleus in the brain stem.  

The morphological characteristics and distribution of serotonin-immunoreactive terminals within the rat mesencephalic trigeminal nucleus (Me5) were studied using immunocytochemical electron microscopy.  

Although almost all of the neuronal perikarya were immunoreactive for prostaglandin E2, intense immunoreactivity was observed in the mitral cell layer of the olfactory bulb, layer V of the cerebral neocortex, anterodorsal and reticular nuclei of the thalamus, supraoptic, paraventricular, accessory neurosecretory and lateral mammaillary nuclei of the hypothalamus, mesencephalic trigeminal nucleus, nucleus of the trapezoid body and deep cerebellar nuclei.  

In addition, an intravenous injection of chlorpromazine (8 mg/kg) was found to increase the amplitude of monosynaptic masseteric reflex EMG activity evoked by stimulations of the mesencephalic trigeminal nucleus.  

After fluorescent tracers were applied to the inferior alveolar nerve and the masseter nerve on the same side of the rat, double-labeled neurons were observed in the caudal part of the mesencephalic trigeminal nucleus (Vme), reflecting simultaneous innervation of both the periodontal ligaments and masseter muscle spindles by collaterals of peripheral processes of single Vme neurons..  

Labeled neurons in the amygdala, colliculus superior and mesencephalic trigeminal nucleus were only found following cervical injections; all other mentioned areas and the posterior commissure complex projected to, at least, midthoracic level..  

The mesencephalic trigeminal nucleus (Mes V) of Protopterus and Neoceratodus contains about 540-590 neurons on each side.  

Also, the conditioning stimulation influenced neither the evoked potentials induced by the tooth pulp stimulation at the main sensory and rostral nuclei nor the jaw-closing reflex induced by the stimulation of the mesencephalic trigeminal nucleus (Mes V).  

First, some neurons contain high levels of LNGF-R mRNA from postnatal time points into adulthood, as exemplified by neurons of the cholinergic basal forebrain and mesencephalic trigeminal nucleus.  

Major calretinin-immunoreactive neurons were found in the lateral and medial geniculate nuclei, substantia nigra, ventral tegmental area, interpeduncular nucleus, periaqueductal gray, mesencephalic trigeminal nucleus, superior and inferior colliculi, pontine nuclei, parabrachial nucleus, dorsal and laterodorsal tegmental nuclei, cochlear nuclei, vestibular nuclei, medullary reticular nuclei, nucleus of the solitary tract, area postrema, substantia gelatinosa of the spinal trigeminal nucleus, and cerebellum.  

A small number of neuronal populations with embryonic expression of NGFR remain strongly NGFR-positive in the posthatch animal:habenular nuclei (labeled after E5), nucleus subrotundus (after E9), mesencephalic trigeminal nucleus (after E5), caudal parts of locus ceruleus and nucleus subceruleus (after E7), medullar reticular nuclei (after E11), and motor nuclei IX, X, and XII (after E9).  

Somata and fibers show NGFr-IR within the trigeminal ganglion and the mesencephalic trigeminal nucleus.  

Retrograde labeling in the brain was observed in only the mesencephalic trigeminal nucleus in these cases.  

Projections of the parvocellular reticular nucleus (PCRt) to the contralateral mesencephalic trigeminal nucleus (Me5) were studied in the rat with neurophysiological and neuroanatomical techniques.  

Several areas had a higher concentration of cells that express connexin43, such as layer IA of the piriform cortex, supraoptic and paraventricular nuclei of the hypothalamus, anterior cortical amygdaloid nucleus, the reticular part of the substantia nigra, lateral habenula, mesencephalic trigeminal nucleus.  

We have studied the localization, the morphology and sources of serotonergic input on the primary afferent neurons in the mesencephalic trigeminal nucleus (Me5) of the rat with light and electronmicroscopy immunocytochemistry and with anterograde and retrograde neuroanatomical tract tracing methods.  

Dense innervations from the rostral parvocellular reticular formation were found in the mesencephalic trigeminal nucleus, the supratrigeminal area, the motor trigeminal nucleus, the motor trigeminal nucleus, the facial, hypoglossal and parabrachial nuclei and specific parts of the caudal parvocellular reticular formation, including nucleus linearis and the dorsal reticular nucleus of the medulla.  

The ratio of masseter primary afferent neurons in the mesencephalic trigeminal nucleus (Vme) to that in the trigeminal ganglion (TG) was found to be 7.7-8.5:1 following injection of HRP into the masseter nerve.  

Fluoro-Gold-accumulating neurons were present in the following regions or cell groups of the central nervous system: diagonal band of Broca; medial preoptic area; organum vasculosum of the lamina terminalis; subfornical organ; anterior periventricular area; paraventricular nucleus; arcuate nucleus; accessory magnocellular nuclei of the hypothalamus; motor neurons of cranial nerves III-VII, and IX-XII in the brainstem and spinal cord; autonomic ganglionic cells of cranial nerve III (Westphal-Edinger nucleus) in the mesencephalon and the intermediolateral column of the spinal cord; sensory ganglia of the cranial nerve V (mesencephalic trigeminal nucleus); and the C1-C2 and A2 adrenergic cell groups in the medulla.  

Distal dendrites extended to the mesencephalic trigeminal nucleus, the supratrigeminal nucleus, the lateral lemniscus and the reticular formation. Unipolar cell bodies of muscle spindle afferents were found in the mesencephalic trigeminal nucleus after intra-axonal injection of horseradish peroxidase.  

After CT injections in the TMN, retrogradely labeled neurons were most frequently seen bilaterally in the nuclei reticularis parvicellularis and dorsalis of the medulla oblongata, the alaminar spinal trigeminal nucleus (magnocellular division), and the adjacent pontine juxtatrigeminal region and in the ipsilateral mesencephalic trigeminal nucleus.  

Anatomical development of the human mesencephalic trigeminal nucleus was assessed quantitatively and qualitatively, using serial sections of brains, with the help of a computer-assisted image-analyser. Morphometric analyses of the mesencephalic trigeminal nucleus revealed that orocaudal columnar length and neuronal areas gradually increased with gestational age.  

The localization and sources of dopaminergic projections on the primary afferent neurons in the mesencephalic trigeminal nucleus (Me5) of the rat were studied using light and electron microscopic immunocytochemical staining techniques combined with anterograde and retrograde neuroanatomical tract tracing methods.  

In addition to motoneurons, labelled cells corresponding to the sensory receptors were found in both the Gasser ganglion and the mesencephalic trigeminal nucleus.  

By contrast, in the central nervous system, neurons of the mesencephalic trigeminal nucleus extend toward the rhombencephalon independently, ignoring preexisting fibers.  

The enzymatic activities of aspartate aminotransferase, GABA-transaminase and acetylcholinesterase were studied by means of histochemical methods in the mesencephalic trigeminal nucleus (MTN) neural complex of the turtle Mauremys caspica.  

The masseteric reflex was elicited by electrical stimulation of the mesencephalic trigeminal nucleus, and the response was recorded via electrodes permanently implanted in the masseter muscle.  

The masseteric reflex was elicited in behaving cats by electrical stimulation of the mesencephalic trigeminal nucleus (MesV) and the response recorded via electrodes permanently placed in the masseter muscle.  

The arrangement between astrocytes and the primary afferent neurons of the mesencephalic trigeminal nucleus (Me5) was analyzed in a light and electron microscopy immunocytochemistry study using anti-GFAP antibodies.  

In order to determine which neurotransmitters and neuropeptides are utilized by the neurons of the mesencephalic trigeminal nucleus and by the fibres making synaptic contact with these primary sensory cells, we have set up an immunohistochemical study using antibodies against 17 major neurotransmitters and neuropeptides in the rat.  

Labelled cells were found in the caudal half of the ipsilateral mesencephalic trigeminal nucleus, in the area where ganglionic cells of the sensory receptors in the extraocular muscles have previously been described. Some cells in the mesencephalic trigeminal nucleus were found to contain both tracers, providing evidence that vestibular neurons do receive direct afferent signals from extraocular muscles.  

Previously unreported projections to the paraoculomotor central gray area and the mesencephalic trigeminal nucleus were observed following dorsomedial PFC injections.  

In addition to basal forebrain magnocellular neurons, NGF-R is widely expressed within the CNS, including neurons of the caudate/putamen, ventral premamillary nucleus, mesencephalic trigeminal nucleus, prepositus hypoglossal nucleus, raphe nucleus, nucleus ambiguous, and Purkinje cells of the cerebellum.  

In all prednisolone-treated cats, labeled neurons were found in both the mesencephalic trigeminal nucleus and trigeminal ganglion, ipsilaterally.  

A light microscopic study in adult cats provided evidence suggesting that neuronal cell bodies of mesencephalic trigeminal nucleus neurons were often in direct contact with axonal varicosities showing enkephalin-, substance P- or serotonin-like immunoreactivity..  

In the trigeminal system, B30 labels the surface of neurons, including their axons and their transient dendrites, in 2 groups of cells: the centrally located mesencephalic trigeminal nucleus and the peripheral trigeminal ganglion.  

The possible relationship of this nucleus with the mesencephalic trigeminal nucleus of jawed vertebrates is discussed..  

Labeled cell bodies were observed both in the trigeminal ganglion and in the mesencephalic trigeminal nucleus.  

Lesioning of the mesencephalic trigeminal nucleus (Mes V) where the primary ganglion cells of muscle spindle afferents from jaw-closing muscles and some periodontal afferents are located, also reduced the facilitative effects.  

In the medulla only axonal degeneration was observed and was confined to three fiber systems: the dorsal column pathway, the sensory trigeminal fibers (both from the trigeminal ganglion and from the mesencephalic trigeminal nucleus), and the spinocerebellar fibers entering the cerebellum through the inferior and superior cerebellar peduncles.  

Cells of the mesencephalic trigeminal nucleus were retrogradely labeled following HRP application to the ophthalmic, maxillary, and mandibular branches of the trigeminal nerve.  

Intracellular recordings were performed in a midpontine slice preparation of the rat brain containing the mesencephalic trigeminal nucleus (MTN).  


-
[ View All ]