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Pierre Buisseret - One of the best experts on this subject based on the ideXlab platform.
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Primary Trigeminal afferents to the vestibular nuclei in the rat: existence of a collateral projection to the vestibulo-cerebellum.
Neuroscience Letters, 1999Co-Authors: Gabrielle Pinganaud, Catherine Buisseret-delmas, Florence Bourcier, Pierre BuisseretAbstract:Projections from the Mesencephalic Trigeminal Nucleus to the vestibular nuclei were analyzed using retrograde and anterograde tracing methods. The results show that neurons in the caudal part of the Trigeminal Mesencephalic Nucleus project mainly to the medial, inferior and lateral vestibular nuclei and moderately to the peripheral part of the superior vestibular Nucleus. Using the double-labeling technique we demonstrate that individual neurons of the Mesencephalic Nucleus send collaterals to the vestibular nuclei and the vestibulo-cerebellum. These results suggest that these anatomical connections are involved in mechanisms of eye-head coordination.
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Projection from Trigeminal nuclei to neurons of the Mesencephalic Trigeminal Nucleus in rat.
Neuroscience letters, 1997Co-Authors: Catherine Buisseret-delmas, Gabrielle Pinganaud, Claude Compoint, Pierre BuisseretAbstract:The Mesencephalic Trigeminal Nucleus contains cell bodies of primary somatic sensory neurons that innervate the head region. The neurons resemble dorsal root ganglion cells but a striking difference is the presence of synaptic boutons in the Nucleus. The present report demonstrates with anterograde tracers, the existence of a direct Trigeminal projection from secondary sensory neurons of the principal and spinal nuclei to the Mesencephalic Nucleus. Our observations strongly suggest that synaptic contact may be established on the cell bodies as well as on the neurites of the Mesencephalic neurons. These pathways could play a modulatory role in the processing of sensory afferent information and in the control of orofacial and/or oculomotor functions.
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Cerebellar afferences from the Mesencephalic Trigeminal Nucleus in the rat.
Neuroreport, 1995Co-Authors: Isabelle Billig, Catherine Buisseret-delmas, Claude Compoint, Najiya Yatim, Pierre BuisseretAbstract:THE aim of the present study was to test for and characterize the organization of a direct projection from neurones of the Trigeminal Mesencephalic Nucleus (Vme) to the cerebellum. WGA-HRP was used as a retrograde tracer following injections in the cerebellar cortex. The extent of each injection site within the sagittal zones was determined according to corticonuclear and olivocortical connections. Retrogradely labelled neurones were observed in the caudal part of the ipsilateral Vme only following vermal injection. The Vme projections reached exclusively the ipsilateral sagittal zone X in the anterior lobe, lobule VI and lobule IX. This identification was confirmed by anterograde labelling of mossy fibre terminals following a biocytin injection restricted to the Vme.
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The vestibular nuclei of the cat receive a primary afferent projection from receptors in extraocular muscles.
Experimental brain research, 1990Co-Authors: C. Buisseret-delmas, M. Epelbaum, Pierre BuisseretAbstract:The vestibular nuclei of adult cat were injected with retrogradely transported tracers, WGA-HRP or fluorescent Diamidino-Yellow. 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. Double labelling experiments were carried out with Diamidino Yellow injected in vestibular nuclei and Fast Blue in extraocular muscles. 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. Therefore, this anatomical demonstration suggests a direct feed-back control between the extraocular muscle receptors and the vestibular nuclei.
J.d. Van Willigen - One of the best experts on this subject based on the ideXlab platform.
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Serotonin-immunoreactive terminals in the Mesencephalic Trigeminal Nucleus of the rat : an electron microscopic immunocytochemical study
Acta anatomica, 1993Co-Authors: Robert S.b. Liem, J.c.v.m. Copray, J.d. Van WilligenAbstract:The morphological characteristics and distribution of serotonin-immunoreactive terminals within the rat Mesencephalic Trigeminal Nucleus (Me5) were studied using immunocytochemical electron microscopy
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Projections of the parvocellular reticular formation to the contralateral Mesencephalic Trigeminal Nucleus in the rat.
Brain research, 1991Co-Authors: R.f. Minkels, P.j.w. Jüch, G.j. Ter Horst, J.d. Van WilligenAbstract:Projections of the parvocellular reticular Nucleus (PCRt) to the contralateral Mesencephalic Trigeminal Nucleus (Me5) were studied in the rat with neurophysiological and neuroanatomical techniques. Three types of responses (classified by latencies) were recorded extracellularly in the Me5 area after electrical stimulation of the PCRt: (1) R1 fast unitary reactions (latency 0.2-0.5 ms) found throughout the entire caudal Me5 area; (2) R2 slower unitary reactions (latency 0.7-1.2 ms) recorded ventral and lateral to the caudal Me5; and (3) R3 compound potentials (latency 1.0-2.5 ms) recorded within the ventrocaudal Me5. Relayed or synaptic fields were not observed. Intracellular recordings of identified cell bodies of periodontal afferents, muscle spindle afferents and interneurones revealed no short-term postsynaptic potentials following PCRt stimulation. In some experiments jaw muscle spindle afferent activity was increased by PCRt stimulation and jaw-opening and jaw-closing reflexes were facilitated in the contralateral musculature. Neuroanatomical experiments, using Phaseolus vulgaris leucoagglutinin as an anterograde tracer, showed direct projections with intensive collateralization of PCRt fibres into the Me5 area. Synaptic contacts of PCRt fibres with primary afferent cell bodies were observed in the ventrocaudal parts of the Me5 only. The electrophysiological results are discussed in relation to the neuroanatomical findings.
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Origin, distribution and morphology of serotonergic afferents to the Mesencephalic Trigeminal Nucleus of the rat.
Neuroscience letters, 1991Co-Authors: J C Copray, R S Liem, G J Ter Horst, J.d. Van WilligenAbstract: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. Me5 neurons were found to receive a serotonergic input that is part of a serotonergic fibre plexus extending over the neighbouring parabrachial Nucleus and locus coeruleus. These serotonergic afferents originate predominantly from serotonergic cells in the dorsal raphe Nucleus.
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Ultrastructure of the Rat Mesencephalic Trigeminal Nucleus
Acta anatomica, 1991Co-Authors: Robert S.b. Liem, J.c.v.m. Copray, J.d. Van WilligenAbstract:The subcellular morphology of the Mesencephalic Trigeminal (Me5) Nucleus in the rat was studied by transmission electron microscopy. Most neurons in the thin rostral as well as in the major caudal par
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Dopaminergic afferents to the Mesencephalic Trigeminal Nucleus of the rat a light and electron microscope immunocytochemistry study
Brain research, 1990Co-Authors: J.c.v.m. Copray, Robert S.b. Liem, G.j. Ter Horst, J.d. Van WilligenAbstract: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. Me5 neurons were found to receive a dopaminergic input that is part of a dopaminergic fibre plexus extending over the neighbouring Nucleus parabrachialis and locus coeruleus. These dopaminergic afferents originate from the substantia nigra, the ventral tegmental area and the medial hypothalamus.
Bo Zhang - One of the best experts on this subject based on the ideXlab platform.
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Action potential-triggered somatic exocytosis in Mesencephalic Trigeminal Nucleus neurons in rat brain slices
2012国际生理学学术大会, 2012Co-Authors: Xiaoyu Zhang, Bo Zhang, Pi-fu Luo, Wei Huang, Zuyin Chai, Fei-peng Zhu, Wei Guo, Zhuan ZhouAbstract:The neurons in the Mesencephalic Trigeminal Nucleus(MeV) play essential roles in proprioceptive sensation of the face and oral cavity.The somata of MeV neurons are generally assumed to carry out neuronal functions but not to play a direct role in synaptic transmission.Using whole-cell recording a...The neurons in the Mesencephalic Trigeminal Nucleus(MeV) play essential roles in proprioceptive sensation of the face and oral cavity.The somata of MeV neurons are generally assumed to carry out neuronal functions but not to play a direct role in synaptic transmission.Using whole-cell recording a...中国科学院上海生命科学研究院(Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences)、中国生理学会(Chinese Association for Physiolog1VOL.6
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Action Potential-Triggered Somatic Exocytosis in Mesencephalic Trigeminal Nucleus Neurons in Rat Brain Slices
Biophysical Journal, 2012Co-Authors: Bo Zhang, Xiaoyu Zhang, Wei Huang, Fei-peng Zhu, Liu Tao, Bin Liu, Xu-yao Guo, Zuyin ChaiAbstract:The neurons in the Mesencephalic Trigeminal Nucleus (MeV) play essential roles in proprioceptive sensation of the face and oral cavity. The somata of MeV neurons are generally assumed to carry out neuronal functions but not to play a direct role in synaptic transmission. Using whole-cell recording and membrane capacitance (Cm) measurements, we found that the somata of MeV neurons underwent robust exocytosis (Cm jumps) upon depolarization and with the normal firing of action potentials in brain slices. Both removing [Ca2+]o and buffering [Ca2+]i with BAPTA blocked this exocytosis, indicating that it was completely Ca2+-dependent. In addition, an electron microscopic study showed synaptic-like vesicles approximated to the plasma membrane in somata. There was a single Ca2+-dependent releasable vesicle pool with a peak release rate of 1912 fF/s. Importantly, following depolarization-induced somatic exocytosis, GABA-mediated postsynaptic currents were transiently reduced by 31%, suggesting that the somatic vesicular release had a retrograde effect on afferent GABAergic transmission. These results provide strong evidence that the somata of MeV neurons undergo robust somatic secretion and may play a crucial role in bidirectional communication between somata and their synaptic inputs in the central nervous system.
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Action potential-triggered somatic exocytosis in Mesencephalic Trigeminal Nucleus neurons in rat brain slices
journal of physiology london, 2012Co-Authors: Bo Zhang, Pi-fu Luo, Liu Tao, Zhang Xiao-yu, Huang Wei, Zhu Fei-peng, Wu Qi-hui, Lu Jin, Xiu YunAbstract:The neurons in the Mesencephalic Trigeminal Nucleus (MeV) play essential roles in proprioceptive sensation of the face and oral cavity. The somata of MeV neurons are generally assumed to carry out neuronal functions but not to play a direct role in synaptic transmission. Using whole-cell recording and membrane capacitance (C-m) measurements, we found that the somata of MeV neurons underwent robust exocytosis (C-m jumps) upon depolarization and with the normal firing of action potentials in brain slices. Both removing [Ca2+](o) and buffering [Ca2+](i) with BAPTA blocked this exocytosis, indicating that it was completely Ca2+ dependent. In addition, an electron microscopic study showed synaptic-like vesicles approximated to the plasma membrane in somata. There was a single Ca2+-dependent releasable vesicle pool with a peak release rate of 1912 fF s(-1). Importantly, following depolarization-induced somatic exocytosis, GABA-mediated postsynaptic currents were transiently reduced by 31%, suggesting that the somatic vesicular release had a retrograde effect on afferent GABAergic transmission. These results provide strong evidence that the somata of MeV neurons undergo robust somatic secretion and may play a crucial role in bidirectional communication between somata and their synaptic inputs in the central nervous system.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000300685900012&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701NeurosciencesPhysiologySCI(E)CPCI-S(ISTP)PubMed8ARTICLE4753-76259
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Action potential-triggered somatic exocytosis in Mesencephalic Trigeminal Nucleus neurons in rat brain slices.
The Journal of physiology, 2011Co-Authors: Bo Zhang, Xiaoyu Zhang, Pi-fu Luo, Wei Huang, Fei-peng Zhu, Liu Tao, Yun XiuAbstract:Non-technical summary Ca2+-regulated axon terminal exocytosis is essential for neuronal communication in the CNS. Besides, the somata may also undergo Ca2+-dependent exocytosis in some neurons in the brain. In the present work we recorded activity/Ca2+-dependent secretion in somata of the Mesencephalic Trigeminal Nucleus (MeV). Following nerve activity, somatic secretion signals are recorded as changes in membrane surface area, as measured by the membrane capacitance. The depolarization-induced somatic exocytosis correlates with transient reduction in the GABA-mediated postsynaptic currents. These results implicated that the somatic secretion may play a role in bidirectional communication between pre- and post-connected neurons in the sensory MeV brain slice neurons.
N. Lazarov - One of the best experts on this subject based on the ideXlab platform.
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Localization of orexin-A-immunoreactive fibers in the Mesencephalic Trigeminal Nucleus of the rat.
Brain research, 2005Co-Authors: Irina I. Stoyanova, N. LazarovAbstract:Abstract Orexin A is a neuropeptide located exclusively in neurons in the hypothalamic nuclei involved in the central regulation of many brain functions, related to motor activity and state-dependent processes. Orexins modulate behavioral state via actions across multiple terminal fields. 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. Orexin-A-immunostained nerve fibers and terminals were found in a close apposition to the perikarya of primary afferent neurons in the MTN with a marked rostrocaudal gradient in their density. In the caudal pontine MTN, only scattered orexin-A-immunoreactive fibers were found, while more rostrally in the pons, and in the midbrain–pontine junction part of the Nucleus, orexin-A-immunopositive varicosities were relatively more abundant, located in close proximity to or often surrounding the neuronal profiles. At the level of the inferior or superior colliculi, a large number of orexin-A-containing neuronal processes and terminal arborizations were observed traveling toward and contacting Mesencephalic Trigeminal neurons, some of which were multipolar. The results of this study show that MTN neurons receive orexin A hypothalamic innervation with a somatotopic arrangement of the projections in the Nucleus. The central orexinergic system may exert direct influence upon jaw movements at the level of the MTN and thus to participate in the control of feeding behavior.
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comparative analysis of the chemical neuroanatomy of the mammalian Trigeminal ganglion and Mesencephalic Trigeminal Nucleus
Progress in Neurobiology, 2002Co-Authors: N. LazarovAbstract:A characteristic peculiarity of the Trigeminal sensory system is the presence of two distinct populations of primary afferent neurons. Most of their cell bodies are located in the Trigeminal ganglion (TG) but part of them lie in the Mesencephalic Trigeminal Nucleus (MTN). This review compares the neurochemical content of central versus peripheral Trigeminal primary afferent neurons. In the TG, two subpopulations of primary sensory neurons, containing immunoreactive (IR) material, are identified: a number of glutamate (Glu)-, substance P (SP)-, neurokinin A (NKA)-, calcitonin gene-related peptide (CGRP)-, cholecystokinin (CCK)-, somatostatin (SOM)-, vasoactive intestinal polypeptide (VIP)- and galanin (GAL)-IR ganglion cells with small and medium-sized somata, and relatively less numerous larger-sized neuropeptide Y (NPY)- and peptide 19 (PEP 19)-IR Trigeminal neurons. In addition, many nitric oxide synthase (NOS)- and parvalbumin (PV)-IR cells of all sizes as well as fewer, mostly large, calbindin D-28k (CB)-containing neurons are seen. The majority of the large ganglion cells are surrounded by SP-, CGRP-, SOM-, CCK-, VIP-, NOS- and serotonin (SER)-IR perisomatic networks. In the MTN, the main subpopulation of large-sized neurons display Glu-immunoreactivity. Additionally, numerous large MTN neurons exhibit PV- and CB-immunostaining. On the other hand, certain small MTN neurons, most likely interneurons, are found to be GABAergic. Furthermore, NOS-containing neurons can be detected in the caudal and the Mesencephalic-pontine junction portions of the Nucleus. Conversely, no immunoreactivity to any of the examined neuropeptides is observed in the cell bodies of MTN neurons but these are encircled by peptidergic, catecholaminergic, serotonergic and nitrergic perineuronal arborizations in a basket-like manner. Such a discrepancy in the neurochemical features suggests that the differently fated embryonic migration, synaptogenesis, and peripheral and central target field innervation can possibly affect the individual neurochemical phenotypes of Trigeminal primary afferent neurons.
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Calcium-binding proteins in the Mesencephalic Trigeminal Nucleus of the cat.
Archives of physiology and biochemistry, 1998Co-Authors: N. Lazarov, A. Dandov, I. Stoyanova, C. ChouchkovAbstract:The presence and distribution of two calcium-binding proteins (CaBPs), parvalbumin (PV) and calbindin D-28k (CB) were immunohistochemically examined in the Mesencephalic Trigeminal Nucleus (MTN) of normal untreated cats and after peripheral nerve injury to the masseteric nerve. Under normal conditions, many PV-immunoreactive (IR) neurons were distributed throughout the whole rostrocaudal extent of MTN, although those in its pontine part were predominant. All immunopositive cells were medium-to-large in size and round-to-oval in appearance. A large number of CB-IR neurons was also found in the intact MTN. Following unilateral peripheral axotomy of the masseteric nerve, the distribution of both CaBPs in the MTN contralaterally to the transection side was very similar to that in untreated animals. However, by combining retrograde labeling of axotomized neurons with immunohistochemistry, a pattern of CaBPs-like immunoreactivity (LI) that changed with time was established. For example, on the side ipsilateral ...
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Neurochemistry of the cat Mesencephalic Trigeminal Nucleus
Biomedical Reviews, 1997Co-Authors: N. Lazarov, C. ChouchkovAbstract:This review is a summary of our current knowledge of the localization of the neurotransmitters excitatory and inhibitory amino acids, monoamines, neuropeptides and nitric oxide in the Mesencephalic Trigeminal Nucleus (MTN) of the cat. Particular emphasis is given to identifying the possible physiological involvement of MTN inputs in the transmission of proprioceptive information at the first synaptic relay. It is shown that the large MTN neuron population contains only glutamate that is a strong candidate for a major neurotransmitter in this brain region. However, certain small MTN neurons, most likely interneurons, are found to be gamma-aminobutyric acid (GABA)-ergic. Furthermore, nitric oxide synthase immunoreactivity can be detected in the caudal as well as the Mesencephalic-pontine junction parts of the MTN and this suggests a mediatory role for nitric oxide in some aspects of synaptic transmission in the MTN. No immunoreactivity to any of the neuropeptides examined is observed in the cell bodies of MTN neurons and only fibers and their terminals show peptide-immunolabelling. Most of the labeled peptidergic fibers have immunopositive varicosities that form pericellular basket-like arborizations around unlabelled MTN perikarya. Together with earlier studies from other laboratories, the present results give strong evidence for the occurrence of both excitatory (glutamatergic) and inhibitory (GABAergic) transmission in the cat MTN. In addition, MTN receives synaptic inputs from peptidergic fibers and these will play a significant role in the Trigeminal proprioceptive afferent transmission. Potential factors and mechanisms regulating neurochemical events in the MTN neurons are discussed. Biomedical Reviews 1997; 8: 1-20.
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Peptidergic innervation of the Mesencephalic Trigeminal Nucleus in the cat
The Anatomical record, 1996Co-Authors: N. Lazarov, C. ChouchkovAbstract:of the peptidergic innervation of the cat MTN. Methods: The distribution of immunoreactive substances was studied using specific antisera against 11 major neuropeptides. Light and electron microscopic peroxidase-antiperoxidase immunocytochemical staining techniques in colchicine-treated animals were used to clarify the distribution of peptide-identified fibers related to the MTN. Results: Immunoreactivity to any of the tested neuropeptides could not be detected in the MTN cell bodies. Numerous fibers containing various peptides such as substance P, bombesin, enkephalins, cholecystokinin, vasoactive intestinal polypeptide, vasopressin, and neuropeptide Y were present in the Nucleus, however. These thin positive fibers covered the neuronal surface of the MTN cell bodies and some of the immunoreactive varicosities appeared to be in close proximity to profiles of MTN neurons. Electron microscopic observations revealed that perisomatic fibers were in direct apposition to perikarya of unstained large cells and some of them made synaptic contacts with their cell bodies and dendrites. Conclusions: The present results demonstrate that the MTN neurons receive dense basket-like innervation from peptidergic neurons on somata and processes and have supported earlier evidence that the MTN of the cat is under influence of peptidergic input. Results of this study provide further evidence that the neuropeptides examined may play an important role in the integration and transmission of Trigeminal proprioceptive information. Most likely they may co-exist with a classical but hitherto unknown neurotransmitter(s), that is unique for this region and whose release can be modulated by peptides.
Kojiro Kurisu - One of the best experts on this subject based on the ideXlab platform.
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The effects of peripheral nerve injury of the masseteric nerve on the levels of calcium binding proteins and neuropeptide Y, and their correlation in the Mesencephalic Trigeminal Nucleus of the rat.
Brain research, 1996Co-Authors: Satoshi Wakisaka, S.h. Youn, Y. Miyawaki, Kojiro KurisuAbstract:Abstract 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. In the normal MesV, many medium- to large-sized unipolar PV-like immunoreactive (-IR) cells were detected through the entire rostrocaudal extent, but CB-IR cells were rarely observed. No NPY-IR cells were observed in the normal MesV. The distributions of these three neurochemical markers in the MesV contralateral to the transection of Mass were almost identical to those observed in the normal MesV. Four days following transection and application of FG to the MassN, approximately 52% (572/1104) and 38% (414/1104) of FG-labeled cells (FG cells) in the MesV displayed PV-like immunoreactivity (-LI) and NPY-LI, respectively; Approximately 24% (265/1104) of FG cells showed both PV-LI and NPY-LI. Approximately 47% (265/572) of FG cells with PV-LI showed NPY-LI or 64% (265/414) of FG cells with NPY-LI displayed PV-LI. Fourteen days following transection and application of FG, the percentage of FG cells with PV-LI significantly decreased to 36% (365/1024) compared to that observed 4 days post-injury; approximately 44% (448/1024) of FG cells displayed NPY-LI; approximately 38% (141/365) of FG cells with PV-LI showed NPY-LI and approximately 31% (141/448) of FG cells with NPY-LI displayed PV-LI. In contrast, FG cells showing CB-LI were very rare on 4 days (1%; or 14 days (1%; 16/1085) following MassN transection. The present results indicate that the levels of PV in the MesV decreased 14 days following the MassN injury compared to those observed 4 days post-injury and rapid induction of NPY in the injured MesV neurons, and that the correlation between CaBP and NPY in the MesV following the MassN transection is different from that observed in the Trigeminal ganglion, which is equivalent to the MesV, following peripheral nerve injury of the inferior alveolar nerve.
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Induction of Fos protein in the rat Trigeminal Nucleus complex during an experimental tooth movement.
Archives of oral biology, 1994Co-Authors: J. Kato, Satoshi Wakisaka, Makoto J. Tabata, Y. Sasaki, Kojiro KurisuAbstract:The induction and temporal changes of Fos protein in the rat spinal Trigeminal Nucleus complex during experimental tooth movement were studied immunohistochemically. Separating elastics were unilaterally inserted between the upper molars. 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. Cells showing Fos immunoreactivity were observed in the superficial layers of the subNucleus caudalis on the ipsilateral side except at 0 and 24 h. The numbers of the immunoreactive cells peaked 2 and 4 h after the insertion. On the contralateral side, only a few immunoreactive cells were observed in the subNucleus caudalis of the 1-, 2- and 4-h groups. 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. Thus experimental tooth movement induced a Fos protein in the superficial layers of the subNucleus caudalis of the spinal Trigeminal Nucleus complex. The subNucleus caudalis may modulate pain induced by tooth movement.