Bartha strain of pseudorabies virus[PRV-Ba] was utilized as a tracer to identify the neuronal axis of rat tongue muscles ; intrinsic muscles and extrinsic muscles, styloglossus, genioglossus, and hyoglossus muscle. After injection of 10 microliter of PRV-Ba into tongue muscles and 48-96 hours survivals, rats were perfused with 4% paraformaldehyde lysine periodate and brains were removed. PRV-Ba were localized in neural circuits by immunohistochemistry employing rabbit anti PRV-Ba as a primary antibody and ABC method. Injection of PRV-Ba into the tongue muscles resulted in uptake and retrograde transport of PRV-Ba in the rat brain. The result showed a circuit specific connection of many nerve cell groups along the time sequence : PRV-Ba immunoreactive cells appeared in hypoglossal nucleus and motor trigeminal nucleus ipsilaterally as seen with conventional tracers. Raphe nucleus, prepositus hypoglossal nucleus, spinal trigeminal nucleus, Al, A5 and facial nucleus of rhombencephalon showed immunoreactivity bilaterally. There were positive neurons in parabrachial nucleus, locus ceruleus, mesencephalic trigeminal nucleus, periaqueductal gray and A7 of mesencephalon and paraventricular nucleus, suprachiasmatic nucleus, organum vasculosum of lamina terminalis of diencephalon. Also positive reactions were showed in amygdala, insular cortex, frontal cortex and subfornical organ in telencephalon. Early immunoreactivity was appeared in hypoglossal nucleus and motor trigeminal nucleus, and there were positive neurons in the nuclei of the medulla oblongate, midbrain, pons, hypothalamus, cerebellum and medial preoptic area at middle stage. Subsequently the viral antigens were found in forebrain cell groups, paraventricular nuclei, suprachiasmatic nucleus, lateral hypothalamic area and primary motor cortex in frontal lobe bilaterally at 80-90hrs postinjection. These data demonstrate that the PRV-Ba can across synapses in the central nervous system with projection specific pattern, and this virus defines many elements of the neural network governing tongue. Therefore PRV-Ba are proved as a excellent neurotracer in the tract-tracing researches.
Amygdala ; Animals ; Antigens, Viral ; Axis, Cervical Vertebra ; Brain ; Central Nervous System ; Cerebellum ; Diencephalon ; Frontal Lobe ; Hypothalamic Area, Lateral ; Hypothalamus ; Immunohistochemistry ; Locus Coeruleus ; Lysine ; Mesencephalon ; Motor Cortex ; Muscles ; Neural Pathways* ; Neurons ; Paraventricular Hypothalamic Nucleus ; Periaqueductal Gray ; Pons ; Preoptic Area ; Prosencephalon ; Pseudorabies ; Raphe Nuclei ; Rats* ; Rhombencephalon ; Subfornical Organ ; Suprachiasmatic Nucleus ; Synapses ; Telencephalon ; Tongue* ; Trigeminal Nuclei ; Trigeminal Nucleus, Spinal

Acute peripheral facial palsy usually manifests Bell's palsy of unknown cause, and rarely lacunar infarct which located in facial nucleus can mimic peripheral facial palsy. A 73 year-old man with isolated facial asymmetry diagnosed with lacunar infarction which selectively involve the facial fascicles which lie in inferolateral aspect of pons. Clinicians should take into account the possibility of central lesion and brain stem infarction, even when patients present with isolated peripheral type facial palsy.
Bell Palsy ; Brain Stem Infarctions ; Facial Asymmetry ; Facial Nucleus ; Facial Paralysis* ; Humans ; Pons ; Stroke, Lacunar

BACKGROUND AND OBJECTIVES: The transsynaptic transfer of neurotropic viruses is an effective tool for tracing chains of connected neurons, because replication of virus in the recipient neurons after the transfer amplifies the "tracer signal". The aim of this study is to identify the central neural pathways projecting to the facial nerve using the Bartha strain of the Pseudorabies virus (PRV-Ba )as a transsynaptic tracer. MATERIALS AND METHODS: PRV-Ba was injected into the facial nerve in the stylomastoid foramen of a rat, and was localized in the rat brain with light microscopic immunohistochemistry using primary antibodies against the PRV-Ba. Sequential tracing was carried out on the retrogradely labeled neurons were done. RESULTS: The shapes of upper motor neurons of facial nerve were mostly ovoid or polygonal. The positive immunoreactive cells observed in the brainstem nuclei included raphe obscurus nucleus, facial nucleus, parvocellular reticular nucleus, spinal trigeminal nucleus, ventral parabrachial nucleus, central gray, and dorsal raphe nucleus. Other positive cells stained in the diencephalon were found in periventricular hypothalamic nucleus, dorsal hypothalamic area, orbital gyri, and infralimbic cortex in the frontal lobe. CONCLUSIONS: These results show the central neural pathways of facial nerve using PRV-Ba.
Animals ; Antibodies ; Brain ; Brain Stem ; Diencephalon ; Facial Nerve ; Frontal Lobe ; Herpesvirus 1, Suid ; Immunohistochemistry ; Motor Neurons ; Neural Pathways* ; Neurons ; Orbit ; Raphe Nuclei ; Rats ; Trigeminal Nucleus, Spinal

A pontine hemorrhage can evoke several neurological symptoms because the pons contains various nuclei and nerve fibers. Hearing loss can develop as a result of a pontine hemorrhage because there is an auditory conduction pathway in the cochlear nucleus of the pons. However, very few cases of hearing loss caused by pontine lesions have been reported, and there have been no reports of auditory neuropathy that developed following a pontine hemorrhage. Recently we had a patient who experienced a nontraumatic pontine hemorrhage who was diagnosed with auditory neuropathy. The 34-year-old male patient was admitted to the emergency department with sudden alteration of mental status. His brain computed tomographic imaging revealed a hemorrhage in the central pons. He complained of hearing difficulties after his mental status recovered through conservative treatment, but a pure-tone audiogram showed very mild hearing loss in both ears. Further hearing tests using otoacoustic emissions, which showed normal responses, and auditory brainstem responses, which showed no waveforms at maximum stimulus intensity, revealed that his hearing difficulties were caused by auditory neuropathy. This case implies that the threshold of sound detection can be preserved in patients with pontine hemorrhage who complain of hearing difficulties. Auditory neuropathy should be considered as a possible cause of hearing difficulties in these patients and appropriate hearing tests should be performed.
Adult* ; Brain ; Cochlear Nucleus ; Ear ; Emergency Service, Hospital ; Evoked Potentials, Auditory, Brain Stem ; Hearing ; Hearing Loss ; Hearing Loss, Central ; Hearing Tests ; Hemorrhage* ; Humans ; Male ; Nerve Fibers ; Pons

It is well known that trigeminal nerve injury causes hyperexcitability in trigeminal ganglion neurons, which become sensitized. Long after trigeminal nerve damage, trigeminal spinal subnucleus caudalis and upper cervical spinal cord (C1/C2) nociceptive neurons become hyperactive and are sensitized, resulting in persistent orofacial pain. Communication between neurons and non-neuronal cells is believed to be involved in these mechanisms. In this article, the authors highlight several lines of evidence that neuron-glial cell and neuron macrophage communication have essential roles in persistent orofacial pain mechanisms associated with trigeminal nerve injury and/or orofacial inflammation.
Cell Communication ; Cervical Cord ; Facial Pain ; Inflammation ; Macrophages ; Neurons ; Nociceptors ; Trigeminal Ganglion ; Trigeminal Nerve ; Trigeminal Nerve Injuries ; Trigeminal Nucleus, Spinal

No abstract available.
Hemorrhage ; Hypotension, Orthostatic ; Pons

In the present study, we performed immunohistochemical studies to investigate the detailed distribution of insulin-like growth factor binding protein 7 (IGFBP7) in the central nervous system of adult rats. Twelve adult (4~6 month old) Sprague-Dawley rats were examined in this study. Immunohistochemistry using specific antibodies against IGFBP7 was performed in accordance with the free-floating method. In the present study, IGFBP7 immunoreactivity was observed in the cerebral cortex, hippocampus, brainstem, cerebellum and spinal cord. In the cerebral cortex, heavily stained neurons were seen in layers II-VI. In the hippocampus, pyramidal cells in CA1-3 region were strongly immunoreactive for IGFBP7. Strong immunoreactive neurons were also found in the supraoptic nucleus, paraventricular nucleus, periaqueductal gray and oculomotor nucleus. In the cerebellum, IGFBP7 immunoreactivity was prominent in the Purkinje cells and cerebellar output neurons. IGFBP7-immunoreactive neurons were prominent in the superior vestibular nucleus, cochlear nucleus, trigeminal motor nucleus, nucleus of the trapezoid, and facial nucleus. IGFBP7-immunoreactive neurons were also observed mainly in the anterior horn of the spinal cord. The first demonstration of IGFBP7 localization in the whole brain may provide useful data for the future investigations on the structural and functional properties of IGFBP7.
Adult ; Animals ; Antibodies ; Brain ; Brain Stem ; Carrier Proteins ; Central Nervous System ; Cerebellum ; Cerebral Cortex ; Cochlear Nucleus ; Hippocampus ; Horns ; Humans ; Immunohistochemistry ; Neurons ; Paraventricular Hypothalamic Nucleus ; Periaqueductal Gray ; Purkinje Cells ; Pyramidal Cells ; Rats ; Rats, Sprague-Dawley ; Spinal Cord ; Supraoptic Nucleus ; Trigeminal Nuclei

BACKGROUND: There is a little information about the effect of selective vestibular stimulation on the expression of activity-dependent metabolic markers in the vestibular nuclei. The purpose of this study was to evaluate effect of afferent excitation of the horizontal semicircular canal on expression of phosphorylated ERK1/2 (pERK1/2) and cFos proteins in the vestibular nuclei. METHODS: The horizontal semicircular canal of Sprague-Dawley rats was selectively stimulated by using the sinusoidal horizontal stimulator with 10-minute duration of stimulation. Conventional immunohistochemical method was used to visualize pERK1/2 or cFos immunoreactive neurons in the vestibular nuclei following rotation. RESULTS: Five minutes after stimulation of the horizontal semicircular canal there was a high expression of pERK1/2 protein in the medial vestibular nucleus among 4 major subnuclei of the central vestibular nuclear complex. On the contrary, immunoreactivity of cFos protein was observed in the medial and inferior vestibular nucleus 2 hours after horizontal sinusoidal rotation. The lateral vestibular nucleus was free from the expression of pERK1/2 and cFos proteins in response to excitation of the horizontal semicircular canal. However, in the vestibular nuclei of unilaterally labyrinthectomized rats expression of pERK and cFos proteins was markedly suppressed in ipsi-lesional side as well as contra-lesional side following stimulation of the horizontal semicircular canal. Furthermore no expression of pERK1/2 and cFos protein in the bilateral vestibular nuclei of bilaterally labyrinthectomized rats was noted after stimulation of the horizontal semicircular canal. CONCLUSIONS: Therefore these results of present study suggest that excitatory afferent signals from the peripheral vestibular receptors are essential for protein translation for pERK1/2 and cFos in response to stimulation of the semicircular canal.
Animals ; Neurons ; Protein Biosynthesis ; Rats ; Rats, Sprague-Dawley ; Semicircular Canals* ; Vestibular Nuclei* ; Vestibular Nucleus, Lateral

The generally accepted taste pathway in an animal projects ipsilaterally from the solitary nucleus. However, the path-way of gustatory fibers in the human brainstem has not been sufficiently clarified. A 57-year-old hypertensive man was admitted with sudden dizziness and hemiageusia. A neurological examination revealed also a diminution of taste on the left half of his tongue. A MRI showed a high signal intensity in the right lower pontine area. This case suggests that the unilateral lesion of the pons may lead to contralateral taste disturbances.
Ageusia ; Animals ; Brain Stem ; Cerebral Infarction ; Dizziness ; Facial Nerve ; Humans ; Infarction* ; Magnetic Resonance Imaging ; Middle Aged ; Neurologic Examination ; Pons ; Solitary Nucleus ; Tongue

The calbindin D-28k (CB)-containing neurons in the interstitial nucleus of the spinal trigeminal tract (INV) that receive visceral and orofacial somatic nociceptive information and emanate projections to the parabrachial nuclei (PB) were investigated by the triple-labeled methods of fluorogold (FG) retrograde tracing combined with Fos and CB proteins immunofluorescence histochemistry in the rat. The results showed (1) in the perioral stimulation group, a large number of FG-retrograde labeled and Fos-immunoreactive neurons were found in the paratrigeminal nucleus (PaV) and the dorsal paramarginal nucleus (PaMd) of the INV ipsilateral to FG and formalin injection made to the PB and lips, respectively, while a lot of CB-immunoreactive neurons were distributed in the INV bilaterally; (2) a majority of the FG-retrograde labeled neurons (77.3%) were double-labeled with CB, and 40.7% of them were double-labeled with Fos; about 38.5% of FG/CB double-labeled neurons were FG/CB/Fos triple-labeled in the INV; and (3) in the upper alimentary tract stimulation group, the distribution and the numbers of FG-retrograde labeled, CB-immunoreactive neurons and FG/CB double-labeled neurons in the INV were similar to those of the perioral stimulation group as described above, except that the Fos immunoreactive neurons were distributed in the INV bilaterally, approximately 41.9% of the FG-retrograde labeled neurons were FG/Fos double-labeled, and over half (52.0%) of those double-labeled neurons were FG/CB/Fos triple-labeled. The results indicate that a part of CB-containing neurons in the INV receive orofacial somatic and visceral nociceptive information and that these neurons sent projections directly to the PB. The CB-containing neurons might play an important role in the transmission of the peripheral nociceptive information from INV to PB.
Animals ; Calbindins ; Face ; innervation ; Male ; Medulla Oblongata ; physiology ; Nerve Tissue Proteins ; metabolism ; Neural Pathways ; physiology ; Neurons ; metabolism ; physiology ; Nociceptors ; physiology ; Pain ; metabolism ; physiopathology ; Pons ; physiology ; Rats ; Rats, Sprague-Dawley ; S100 Calcium Binding Protein G ; metabolism ; Trigeminal Nucleus, Spinal ; physiology ; Viscera ; innervation