The ultrastructural parameters related to synaptic release of endings which are presynaptic to tooth pulp afferent terminals (p-endings) were analyzed to understand the underlying mechanism for presynaptic modulation of tooth pulp afferents. Tooth pulp afferents were labelled by applying wheat-germ agglutinin conjugated horseradish peroxidase to the rat right lower incisor, whereafter electron microscopic morphometric analysis with serial section and reconstruction of p-endings in the trigeminal oral nucleus was performed. The results obtained from 15 p-endings presynaptic to 11 labeled tooth pulp afferent terminals were as follows. P-endings contained pleomorphic vesicles and made symmetrical synaptic contacts with labeled terminals. The p-endings showed small synaptic release-related ultrastructural parameters: volume, 0.82 ± 0.45 µm³ (mean ± SD); surface area, 4.50 ± 1.76 µm²; mitochondrial volume, 0.15 ± 0.07 µm³; total apposed surface area, 0.69 ± 0.24 µm²; active zone area, 0.10 ± 0.04 µm²; total vesicle number, 1045 ± 668.86; and vesicle density, 1677 ± 684/µm². The volume of the p-endings showed strong positive correlation with the following parameters: surface area (r=0.97, P<0.01), mitochondrial volume (r=0.56, P<0.05), and total vesicle number (r=0.73, P<0.05). However, the volume of p-endings did not positively correlate or was very weakly correlated with the apposed surface area (r=-0.12, P=0.675) and active zone area (r=0.46, P=0.084). These results show that some synaptic release-related ultrastructural parameters of p-endings on the tooth pulp afferent terminals follow the "size principle" of Pierce and Mendell (1993) in the trigeminal nucleus oralis, but other parameters do not. Our findings may demonstrate a characteristic feature of synaptic release associated with p-endings.
Animals ; Horseradish Peroxidase ; Incisor ; Mitochondrial Size ; Rats ; Tooth* ; Trigeminal Nuclei

We used cholera toxin B subunit (CTB) as a neural tracer to localize motor neuronal cell bodies innervating the digastric muscle. After CTB injection into the left anterior belly, CTB-labelled motor neuronal cell bodies were found in caudal half of the left and right trigeminal nucleus, the left and right facial nucleus, the accessory facial nucleus and the accessory trigeminal nucleus in pons. The total number of CTB-labelled motor neuronal cell bodies were 1,179+/-119.5 in the left pons and 246+/-61.8 in the right pons after CTB injections into the left anterior belly of digastric muscle. After CTB injection into left posterior belly, CTB-labelled motor neuronal cell bodies were found only in the left ventral part of accessory facial nucleus in caudal pons and the total number of CTB-labelled motor neuronal cell bodies were 270+/-29.3.
Animals ; Cholera Toxin* ; Cholera* ; Motor Neurons* ; Pons ; Rats* ; Trigeminal Nuclei

The present study was aimed to investigate the ultrastructure of the primary afferent terminals and whether glutamate may be a transmitter in these terminals within the trigeminal nucleus principalis and oralis of the rat. Labeling of primary afferent terminals was performed by the injection of the CTB-HRP into the trigeminal ganglion. Ultrastructural analysis and assessment of the glutamate like immunoreactivity by the immunogold technique was performed with the 66 peroxidased labeled boutons in the nucleus principalis and 62 in the nucleus oralis. Labeled boutons were presynaptic to dendritic shafts of the secondary neurons and postsynaptic to the pleomorphic vesicles containing endings (p-endings). Most of the labeled boutons made synaptic contact with the dendritic shafts. A little labeled boutons in the nucleus oralis but no in the nucleus principalis was observed to make synaptic contact with the soma or proximal dendrite. Most of the labeled boutons made synaptic contact with one to three neurofiles, but labeled boutons showing complex synaptic connections, such as those with five or more neurofiles, were more in principalis than in oralis. The average diameter of p-endings were smaller than that of labeled boutons (p<0.05). The diameter of the postsynaptic dendritic shafts were smaller in nucleus principalis than in nucleus oralis, thus indicated that the labeled boutons made synaptic contact with more distal portion of the postsynaptic dendrite in the nucleus principalis than in the nucleus oralis. The gold particle density over the labeled boutons were significantly higher than that over the p-endings and average tissue particle density. They were ranged from 110 to 430% of the average tissue particle density. These findings indicate that synaptic connection of the primary afferent terminals is organized in different manner in nucleus principalis and oralis, and suggest that glutamate is involved as neuroactive substance in the primary afferent terminals of the trigeminal system.
Animals ; Carisoprodol ; Dendrites ; Glutamic Acid* ; Immunohistochemistry ; Neurons ; Neurotransmitter Agents ; Rats* ; Trigeminal Ganglion ; Trigeminal Nuclei*

SUNCT syndrome is a headache syndrome characterized by short-lasting(usually 15-120 sec), unilateral head paroxysms localized in the peri-ocular area, accompanied by conjunctival injection, lacrimation, nasal stuffiness, rhinorrhea, and subclinical forehead sweating, all on the symptomatic side. We experienced a new SUNCT syndrome case. 57-year-old patient had been suffering from right orbital pain attacks since he was 54. The pain, of an ""electrical"" or ""burning"" character, was moderate to severe in intensity. Single attacks lasted for 30-60 seconds each and were accompanied by prominent ipsilateral conjunctival injection and tearing as well as slight rhinorrhea. His symptoms were relieved by carbamazepine. Carbamazepine treatment seemingly brought about marked decrease in the frequency and severity of attacks. This case may be the first reported SUNCT syndrome case in Korea. Furthermore this case may shed light on the nosologic point view of SUNCT syndrome. The suspected pathophysiology of trigeminal neuralgia is expansion of the low threshold portions of the receptive fields owing to loss of surround inhibition. Carbamazepine facilitate afferent inhibition and depress excitatory transmission in the trigeminal nucleus. So the effectiveness to carbamazepine has been considered as one of diagnostic criteria of trigeminal neuralgia. Through the survey of previous reported cases including our case, it is suspected that SUNCT syndrome be closer to trigeminal neuralgia rather than cluster headache. We discussed several viewpoints for the nosologic aspect of SUNCT syndrome in this report.
Carbamazepine* ; Cluster Headache ; Forehead ; Head ; Headache Disorders ; Humans ; Korea ; Middle Aged ; Orbit ; SUNCT Syndrome* ; Sweat ; Sweating ; Trigeminal Neuralgia ; Trigeminal Nuclei

Intracranial headaches, including migraines, are mediated by nociceptive activation of the trigeminal nucleus caudalis (TNC), but the precise mechanisms are poorly understood. We previously demonstrated that selective blockage of spinal sigma-1 receptors (Sig-1R) produces a prominent antinociceptive effect in several types of pain models. This study evaluates whether the Sig-1R antagonist (BD1047) has an antinociceptive effect on capsaicin (a potent C-fiber activator) induced headache models in rats. Intracisternal infusion of capsaicin evoked pain behavior (face grooming), which was significantly attenuated by BD1047 pretreatment. BD1047 consistently reduced capsaicin-induced Fos-like immunoreactivity (Fos-LI), a neuronal activator, in the TNC in a dose-dependent manner. Moreover, capsaicin-induced phosphorylation of N-methyl-D-aspartate receptor subunit 1 was reversed by BD1047 pretreatment in the TNC. These results indicate that the Sig-1R antagonist has an inhibitory effect on nociceptive activation of the TNC in the capsaicin-induced headache animal model.
Animals ; Capsaicin ; Headache ; Migraine Disorders ; Models, Animal ; N-Methylaspartate ; Neurons ; Phosphorylation ; Rats ; Receptors, sigma ; Trigeminal Nuclei

The present study has been performed to investigate the neural axis of rat digastric muscle using viral tracer, pseudorabies virus. The upper nuclei to innervate digastric muscle were in accumbens nucleus, agran-ular insular cortex, central nucleus of amygaloid, lateral septal nucleus, frontal cortex, and subfornical organ etc, in telencephalon ; arcuate hypothalamic nucleus, lateral hypot-halamic area, medial preoptic nucleus, bed nucleus of stria terminalis, dorsomedial hypot-halamic nucleus, suprachiasmatic nucleus, paraventricular nucleus, and retrochiasmatic area etc, in diencephalon ; nucleus Darkschewitsch, interstitial nucleus of the medial logitudinal fasciculus, parabrachial nucleus, locus ceruleus, Kolliker-Fuse nucleus, trigeminal mesencephalic nucleus, red nucleus, substantia nigra, nucleus of posterior commissure, Edinger-Westphal nucleus, and dorsal raphe nucleus etc, in mesencephalon ; giganto-cellular reticular nucleus, raphe magnus nucleus, raphe pallidus nucleus, raphe obscuous nucleus, nucleus of solitary tracts, lateral reticular nucleus, parvocellular reticular nucleus, area postrema, facial nucleus, pontine reticular nucleus, pontine nucleus of trigeminal nerve and spinal nucleus of trigeminal nerve etc, in rhombencephalon. There are significant difference of numbers of PRV-Ba immunoreactive cells between right and left sides of brain in almost nuclei[P< 0.05]. But PRV-Ba immunoreactive cells were observed only ipsilaterally in accessory trigeminal motor nucleus, accessory facial nucleus and agranular insular cortex. Frontal cortex was the only area which were shown contralateral immunoreactivity. The results of this study provide anatomical support that both the cranial and caudal bellies are innervated by the same upper nuclei. The results also support the suggestion that the lower nuclei of digastric muscle, accessory trigeminal motor nucleus and accessory facial nucleus consist of somatotopic motor complex.
Animals ; Area Postrema ; Axis, Cervical Vertebra* ; Brain ; Diencephalon ; Herpesvirus 1, Suid ; Hypothalamic Area, Lateral ; Immunohistochemistry ; Locus Coeruleus ; Mesencephalon ; Paraventricular Hypothalamic Nucleus ; Raphe Nuclei ; Rats* ; Red Nucleus ; Rhombencephalon ; Septal Nuclei ; Subfornical Organ ; Substantia Nigra ; Suprachiasmatic Nucleus ; Telencephalon ; Trigeminal Nerve ; Trigeminal Nuclei

BACKGROUND: Zolmitriptan (Zomig) is a selective serotonin agonist at the 5-hydroxytryptamine (5-HT1B/1D) receptor that acts both centrally and peripherally in the trigeminal nucleus and axon terminals and at adjacent meningeal vessels. The clinical efficacy of zolmitriptan in adult migraine has been documented in several placebo-controlled studies, but not studied yet in Korea. METHODS: This multicenter, double-blind, placebo-controlled study was directed to evaluate the efficacy and tolerability of a single 2.5-mg dose of zolmitriptan for the acute treatment of a single moderate or severe migraine attack in Korean patients. A sample consisting of 129 outpatients was randomized to receive either zolmitriptan (n=67) or placebo (n=62). RESULTS: The headache response at 2 hours after treatment was significantly greater in patients receiving zolmitriptan than in patients receiving placebo (52.2% versus 30.7%, p<0.05). At 4 hours, the response rate in the zolmitriptan group (91.5%) was significantly higher than in the placebo group (65.6%; p<0.05). Among the nonheadache symptoms, phonophobia was more relieved in the zolmitriptan group than in the placebo group (p=0.038). There were no clinically serious adverse events that were judged by the physicians to be related to zolmitriptan. CONCLUSIONS: The results of this study demonstrate that zolmitriptan tablets 2.5-mg taken for acute migraine attacks are effective and well-tolerated in Korean patients. (J Korean Neurol Assoc 19(1):29~35, 2001
Adult ; Headache ; Humans ; Hyperacusis ; Korea ; Migraine Disorders* ; Outpatients ; Presynaptic Terminals ; Serotonin ; Serotonin Receptor Agonists ; Tablets ; Trigeminal Nuclei

To analyze the synaptic characteristics of axon terminals originated from the tooth pulp in the trigeminal nucleus oralis, labeling of tooth pulp afferents with wheat-germ agglutinin conjugated horseradish peroxidase and morphometric analysis with electron microscopic photographs were performed. The results obtained from 23 labeled endings were as follows. All of the labeled boutons contained clear and round synaptic vesicles (dia. 45~55 nm). 3 (13.64%) out of 23 labeled endings have 20~105 dense cored vesicles and do not make synaptic contacts with p-endings. But remaining 20 labeled endings (86.36%) almost do not have dense cored vesicles and 12 of them make synaptic contacts with p-endings. The mean number of synaptic contacts was 2.61+/-2.06 and the postsynaptic profiles were usually middle or distal dendrite and dendritic spine (1.74+/-1.36) rather than soma or proximal dendrite. The mean number of synaptic contacts with pendings was 0.87+/-1.01. And the frequency of the synaptic triads were 0.39+/-0.58. The vesicle density was 993.23+/-267.41/mum(2). The volume of labeled bouton was 3.54+/-2.20 mum(3) and highly correlated (P < 0.01) with surface area (11.78+/-4.92 mum(2), r = 0.95), total apposed surface area (2.90+/-1.56 mum(2), r=0.72), total active zone area (0.61+/-0.37 mum(2), r = 0.82), mitochondrial volume (0.75+/-0.53 mum(3), r = 0.94), the number of synaptic vesicles (2621.30+/-1473.61, r= 0.91) and the number of synaptic contacts (r = 0.76). These results suggest that there are two groups of tooth pulp afferent terminals according to the presence of dense cored vesicles in the trigeminal nucleus oralis. And the sensory processing mechanism of each groups may be different. And the "size principle" of Pierce & Mendell (1993) is also applicable to these terminals.
Carisoprodol ; Dendrites ; Dendritic Spines ; Horseradish Peroxidase ; Mitochondrial Size ; Mouth* ; Presynaptic Terminals ; Synapses ; Synaptic Vesicles ; Tooth ; Trigeminal Nuclei*

Nitric oxide(NO) is thought to play an important role in development and plasticity of brain. In this study, we aimed to examine the expression of neuronal NOS and NADPH-diaphorase (NADPH-d) activity in the developing rat brain. The results show that there is a great variation in the time of appearance of the earliest NOS containing cells depending on their location: At the 15th embryonic day weakly stained cells were present in caudate-putamen, and neurons in the sensory trigeminal nucleus and the solitary nucleus displayed an intense staining. The NOS neurons in orbital neocortex, bed nucleus of stria terminalis, paraventricular hypothalamic nucleus, lateral hypothalamic area and mammillary body appeared first at the 18th embryonic day. The supraoptic nucleus and superior and inferior colliculi also weakly labeled at the 18th embryonic day, At the loth embryonic day, positive cells appeared in horizontal limb of diagonal band, anterior olfactory nucleus and parafascicular thalamic nucleus. In the cerebellum, weak NOS staining was present in fibers and cells situated below Purkinje cert layer. The Purkinje cell layer displayed a weak, rather diffuse activity throughout the cerebellum at postnatal day 0. At the 4th postnatal day. the reaction product in the Purkinje cell layer became more distinct. At the 10th postnatal day, the inner part of molecular layer became populated by NOS positive basket cells, and the reaction products on the Purkinje cells began to disappear. The present results showed that NOS in the rat brain is expressed in different populations of neurons at different stages of development. This expression pattern of NOS suggests that NO may play a role in the developmental remodelling of the mammalian brain.
Animals ; Brain* ; Cerebellum ; Extremities ; Hypothalamic Area, Lateral ; Inferior Colliculi ; Intralaminar Thalamic Nuclei ; Mamillary Bodies ; Neocortex ; Neurons ; Nitric Oxide Synthase* ; Nitric Oxide* ; Orbit ; Paraventricular Hypothalamic Nucleus ; Plastics ; Purkinje Cells ; Rats* ; Septal Nuclei ; Solitary Nucleus ; Supraoptic Nucleus ; Trigeminal Nuclei

BACKGROUND: The trigeminal nucleus caudalis (Vc) is a primary central site for trigeminal transmitting. Noxious stimulation of the trigeminal nociceptors alters the central synaptic releases and neural expression of some inflammatory and trophic agents. Orexin-A and the orexin 1 receptor (OX1R) are expressed in pain pathways including trigeminal pain transmission. However, the the mechanism(s) underling orexin-A effects on trigeminal pain modulation have not been fully clarified. METHODS: Trigeminal pain was induced by subcutaneous injection of capsaicin in the upper lip in rats. The effect of trigeminal pain on cyclooxygenase-2 (COX-2) and brain-derived neurotrophic factor (BDNF) expression in the Vc of animals was determined by immunofluorescence. Subsequently, OX1R agonist (orexin-A) and antagonist (SB-334867-A) was administrated in the Vc to investigate the possible roles of the Vc OX1R on changes in COX-2 and BDNF levels following pain induction. RESULTS: The data indicated an increase in COX-2 and decrease in BDNF immuno-reactivity in the Vc of capsaicin, and capsaicin- pretreated with SB-334867-A (80 nM), groups of rat. However, the effect of capsaicin on COX-2 and BDNF expressions was reversed by a Vc microinjection of orexin-A (100 pM). CONCLUSIONS: Overall, the present data reveals that orexin-A can attenuate capsaicin-induced trigeminal pain through the modulation of pain effects on COX-2 and BDNF expressions in the Vc of rats.
Animals ; Brain-Derived Neurotrophic Factor ; Capsaicin ; Cyclooxygenase 2 ; Facial Pain ; Fluorescent Antibody Technique ; Injections, Subcutaneous ; Lip ; Microinjections ; Nociceptors ; Orexin Receptor Antagonists ; Orexins ; Pain Measurement ; Pain Perception ; Rats ; Trigeminal Caudal Nucleus ; Trigeminal Neuralgia ; Trigeminal Nuclei