• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.10a
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• pp.150-152
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• 2022

In this work, we propose a model that considers the behavior and synaptic plasticity of sensory neurons based on Liquid Time-constant Network (LTC). The neuron connection structure was experimented with four types: the increasing number of neurons, the decreasing number, the decreasing number, and the decreasing number. In this study, we experimented using a time series prediction dataset to see if the performance of the changed model improved compared to LTC. Experimental results show that the application of modeling of sensory neurons does not always bring about performance improvements, but improves performance through proper selection of learning rules depending on the type of dataset. In addition, the connective structure of neurons showed improved performance when it was less than four layers.

• Journal of Yeungnam Medical Science
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• v.15 no.1
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• pp.75-96
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• 1998

The local arrangement of sensory nerve cell bodies and nerve fibers in the brain stem, spinal ganglia and nodose ganglia were observed following injection of cholera toxin B subunit(CTB) and wheat germ agglutinin-horseradish peroxidase(WGA-HRP) into the rat intestine. The tracers were injected in the stomach(anterior and posterior portion), duodenum, jejunum, ileum, cecum, ascending colon or descending colon. After survival times of 48-96 hours, the rats were perfused and their brain, spinal and nodose ganglia were frozen sectioned ($40{\mu}m$). These sectiones were stained by CTB immunohistochemical and HRP histochemical staining methods and observed by dark and light microscopy. The results were as follows: 1. WGA-HRP labeled afferent terminal fields in the brain stem were seen in the stomach and cecum, and CTB labeled afferent terminal fields in the brain stem were seen in all parts of the intestine. 2. Afferent terminal fields innervating the intestine were heavily labeled bilaterally gelalinous part of nucleus of tractus solitarius(gelNTS), dorsomedial part of gelNTS, commissural part of NTS(comNTS), medial part of NTS(medNTS), wall of the fourth ventricle, ventral border of area postrema and comNTS in midline dorsal to the central canal. 3. WGA-HRP labeled sensory neurons were observed bilaterally within the spinal ganglia, and labeled sensory neurons innervating the stomach were observed in spinal ganglia $T_2-L_1$ and the most numerous in spinal ganglia $T_{8-9}$. 4. Labeled sensory neurons innervating the duodenum were observed in spinal ganglia $T_6-L_2$ and labeled cell number were fewer than the other parts of the intestines. 5. Labeled sensory neurons innervating the jejunum were observed in spinal ganglia $T_6-L_2$ and the most numerous area in the spinal ganglia were $T_{12}$ in left and $T_{13}$ in right. 6. Labeled sensory neurons innervating the ileum were observed in spinal ganglia $T_6-L_2$ and the most numerous area in the spinal ganglia were $T_{11}$ in left and $L_1$ in right. 7. Labeled sensory neurons innervating the cecum were observed in spinal ganglia $T_7-L_2$ and the most numerous area in the spinal ganglia were $T_{11}$ in left and $T_{11-12}$ in right. 8. Labeled sensory neurons innervating the ascending colon were observed in spinal ganglia $T_7-L_2$ in left, and $T_9-L_4$ in right. The most numerous area in the spinal ganglia were $T_9$ in left and $T_{11}$ in right. 9. Labeled sensory neurons innervating the descending colon were observed in spinal ganglia $T_9-L_2$ in left, and $T_6-L_2$ in right. The most numerous area in the spinal ganglia were $T_{13}$ in left and $L_1$ in right. 10. WGA-HRP labeled sensory neurons were observed bilaterally within the nodose ganglia, and the most numerous labeled sensory neurons innervating the abdominal organs were observed in the stomach. 11. The number of labeled sensory neurons within the nodose ganglia innervating small and large intestines were fewer than that of labeled sensory neurons innervating stomach These results indicated that area of sensory neurons innervated all parts of intestines were bilaterally gelatinous part of nucleus tractus solitarius(gelNTS), dorsomedial part of gelNTS, commissural part of NTS (comNTS), medial part of NTS, wall of the fourth ventricle, ventral border of area postrema and com NTS in midline dorsal to the central canal within brain stem, spinal ganglia $T_2-L_4$ and nodose ganglia. Labeled sensory neurons innervating the intestines except the stomach were observed in spinal ganglia $T_6-L_4$. The most labeled sensory neurons from the small intestine to large intestine came from middle thoracic spinal ganglia to upper lumbar spinal ganglia.

• The Journal of Korean Medicine
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• v.31 no.1
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• pp.93-111
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• 2010

Objectives: The present study was performed to evaluate the potential effects of Bupleuri radix (SH) on regenerative activities in the peripheral sciatic nerve after crushing injury in rats. Methods: Axonal regeneration after crush injury in rats was analyzed by immunofluorescence staining using anti-NF-200 antibody and retrograde tracing of DiI-axons. Changes in protein levels in the sciatic nerve axons and DRG tissue were analyzed by Western blot analysis and immunofluorescence staining. Effects of SH extract treatment on neurite outgrowth was examined by immunofluorescence staining for cultured DRG neurons. Results: Major findings on the effects of SH extract treatment on axonal regeneration are summarized as follows. 1. SH-mediated enhancement in axonal regeneration was identified by immuno- fluorescence straining of NF-200 protein and retrograde tracing of DiI-labeled axons. 2. Axonal GAP-43 protein levels were upregulated by SH not only in the injured axons but also in the DRG sensory neurons corresponding to sciatic sensory axons. 3. Phospho-Erk1/2 protein levels were increased in both injured axonal area and DRG sensory neurons by SH. Phospho-Erk1/2 was also found in non-neuronal cells in the injured axons. 4. SH elevated levels of Cdc2 protein produced in Schwann cells in the distal portions of injured sciatic nerves. 5. The neurite outgrowth of DRG sensory neurons in culture was augmented by SH, and these changes were positively associated with GAP-43 production levels in the DRG neurons. Conclusions: These data suggest that SH extract improves the regenerative responses of injured peripheral neurons, and thus may be useful for understanding molecular basis for the development of therapeutic strategies.

• International Journal of Oral Biology
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• v.46 no.3
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• pp.119-126
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• 2021

Activation of transient receptor potential vanilloid 1 (TRPV1), a calcium permeable channel expressed in primary sensory neurons, induces the release of glutamate from their central and peripheral afferents during normal acute and pathological pain. However, little information is available regarding the glutamate release mechanism associated with TRPV1 activation in primary sensory neurons. To address this issue, we investigated the expression of vesicular glutamate transporter (VGLUT) in TRPV1-immunopositive (+) neurons in the rat trigeminal ganglion (TG) under normal and complete Freund's adjuvant (CFA)-induced inflammatory pain conditions using behavioral testing as well as double immunofluorescence staining with antisera against TRPV1 and VGLUT1 or VGLUT2. TRPV1 was primarily expressed in small and medium-sized TG neurons. TRPV1+ neurons constituted approximately 27% of all TG neurons. Among all TRPV1+ neurons, the proportion of TRPV1+ neurons coexpressing VGLUT1 (VGLUT1+/TRPV1+ neurons) and VGLUT2 (VGLUT2+/TRPV1+ neurons) was 0.4% ± 0.2% and 22.4% ± 2.8%, respectively. The proportion of TRPV1+ and VGLUT2+ neurons was higher in the CFA group than in the control group (TRPV1+ neurons: 31.5% ± 2.5% vs. 26.5% ± 1.2%, VGLUT2+ neurons: 31.8% ± 1.1% vs. 24.6% ± 1.5%, p < 0.05), whereas the proportion of VGLUT1+, VGLUT1+/TRPV1+, and VGLUT2+/TRPV1+ neurons did not differ significantly between the CFA and control groups. These findings together suggest that VGLUT2, a major isoform of VGLUTs, is involved in TRPV1 activation-associated glutamate release during normal acute and inflammatory pain.

• Korean Journal of Acupuncture
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• v.17 no.1
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• pp.101-121
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• 2000

The purpose of this morphological studies was to investigate the relation to the meridian, acupoint and nerve. The common locations of the spinal cord and brain projecting to the the gallbladder, GB34 and common peroneal nerve were observed following injection of transsynaptic neurotropic virus, pseudorabies virus(PRV), into the gallbladder, GB34 and common peroneal nerve of the rabbit. After survival times of 96 hours following injection of PRV, the thirty rabbits were perfused, and their spinal cord and brain were frozen sectioned($30{\mu}m$). These sections were stained by PRV immunohistochemical staining method, and observed with light microscope. The results were as follows: 1. In spinal cord, PRV labeled neurons projecting to the gallbladder, GB34 and common peroneal nerve were founded in thoracic, lumbar and sacral spinal segments. Densely labeled areas of each spinal cord segment were founded in lamina V, VII, X, intermediolateral nucleus and dorsal nucleus. 2. In medulla oblongata, The PRV labeled neurons projecting to the gallbladder, GB34 and common peroneal nerve were founded in the A1 noradrenalin cells/C1 adrenalin cells/caudoventrolateral reticular nucleus, rostroventrolateral reticular nucleus, medullary reticular nucleus, dorsal motor nucleus of vagus nerve, nucleus tractus solitarius, raphe obscurus nucleus, raphe pallidus nucleus, raphe magnus nucleus, gigantocellular nucleus, lateral paragigantocellular nucleus, principal sensory trigeminal nucleus and spinal trigeminal nucleus. 3. In Pons, PRV labeled neurons were parabrachial nucleus, Kolliker-Fuse nucleus and cochlear nucleus. 4. In midbrain, PRV labeled neurons were founded in central gray matter and substantia nigra. 5. In diencephalon, PRV labeled neurons were founded in lateral hypothalamic nucleus, suprachiasmatic nucleus and paraventricular hypothalamic nucleus. 6. In cerebral cortex, PRV labeled neuron were founded in hind limb area.This results suggest that PRV labeled common areas of the spinal cord projecting to the gallbladder, GB34 and common peroneal nerve may be first-order neurons related to the somatic sensory, viscero-somatic sensory and symapathetic preganglionic neurons, and PRV labeled common area of the brain may be first, second and third-order neurons response to the movement of smooth muscle in gallbladder and blood vessels.These PRV labeled neurons may be central autonomic center related to the integration and modulation of reflex control linked to the sensory system monitoring the internal environment, including both visceral sensation and various chemical and physical qualities of the bloodstream. The present morphological results provide that gallbladder meridian and acupoint may be related to the central autonomic pathways.

• The Journal of Korean Medicine
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• v.22 no.2
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• pp.31-40
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• 2001

This experimental studies was to investigate location of labeled neurons in CNS following injection of pseudorabies virus(PRV), Bartha strain, into the uterus and Sanyinjiao(Sp6) of rats. After survival times of 4-5 days following the injection of PRV, the rats were perfused, and their brain and spinal cord were frozen sectioned($30\mu\textrm{m}$). These sections were stained by PRV immunohistochemical staining methods, and observed with light microscope. The results were as follows: 1. In the spinal cord, overlap areas of PRV labeled neurons projecting to uterus and Sp6 were observed in lamina VII, IX and X areas of cervical segments. In thoracic segments, overlap areas were observed in lamina IV, VII, X and intermediolateral n.. In lumbar segments, overlap area of PRV labeled neurons were observed in lamina I, V-VII, IX, X and intermediolateral n.. In sacral segments, overlap areas of PRY labeled neurons were observed in lamina N, V, VII, X and sacral parasympathetic n.. 2. In the brain, overlap areas of PR V labeled neurons projecting to the uterus and Sp6 were observed in lateral paragigantocellular n., rostroventrolateral reticular n., raphe obscurus n., raphe pallidus n., raphe magnus n., locus coeruleus n., Barrington's n., A5 cell group, central gray n., paraventricular hypothalamic n. and arcuate n. This results suggest that overlap areas of PRV labeled neurons of the spinal cord projecting to the uterus and Sp6 might be the first-order neurons related to the viscera-somatic sensory and sympathetic preganglionic neurons. PRV labeled neurons of the brain may be the second and third-order neurons response to the movement of smooth muscle of uterus. These PRV labeled neurons may be central autonomic center related to the integration and modulation of reflex control linked to the sensory and motor system monitoring the internal environment. These overlap areas of spinal cord and brainmay be related to autonomic centers related to regulation of uterus.

• The Korean Journal of Physiology
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• v.28 no.2
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• pp.113-122
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• 1994

The present study was carried out to characterize the functional properties of spinomesencephalic tract (SMT) neurons in the lumbar spinal cord of urethane anesthetized rats. Extracellular single unit recordings were made from neurons antidromically activated by stimulation of the midbrain area, including the deep layers of superior colliculus, periaqueductal gray and midbrain reticular formation. Recording sites were located in laminae I-VII of spinal cord segments of L2-L5. Receptive field properties and responses to calibrated mechanical stimulation were studied in 78 SMT cells. Mean conduction velocity of SMT neurons was $19.1{\pm}1.04\;m/sec$. SMT units were classified according to their response profiles into four groups: wide dynamic range (58%), deep/tap (23%), high threshold (9%) and low threshold (3%). A simple excitatory receptive field was found for most SMT neurons recorded in superficial dorsal horn (SDH). Large complex inhibitory and/or excitatory receptive fields were found for cells in lateral reticulated area which usually showed long after-discharge. Most of SMT cells received inputs from $A{\delta}$ and C afferent fiber types. These results suggest that sensory neurons in the rat SMT may have different functional roles according to their location in the spinal cord in integrating and processing sensory inputs including noxious mechanical stimuli.

• Journal of Ginseng Research
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• v.39 no.3
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• pp.257-264
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• 2015

Background: Korean Red Ginseng-a steamed root of Panax ginseng Meyer-has long been used as a traditional medicine in Asian countries. Its antipruritic effect was recently found, but no molecular mechanisms were revealed. Thus, the current study focused on determining the underlying molecular mechanism of Korean Red Ginseng extract (RGE) against histamine-induced itch at the peripheral sensory neuronal level. Methods: To examine the antipruritic effect of RGE, we performed in vivo scratching behavior test in mice, as well as in vitro calcium imaging and whole-cell patch clamp experiments to elucidate underlying molecular mechanisms. Results: The results of our in vivo study confirmed that RGE indeed has an antipruritic effect on histamine-induced scratching in mice. In addition, RGE showed a significant inhibitory effect on histamine-induced responses in primary cultures of mouse dorsal root ganglia, suggesting that RGE has a direct inhibitory effect on sensory neuronal level. Results of further experiments showed that RGE inhibits histamine-induced responses on cells expressing both histamine receptor subtype 1 and TRPV1 ion channel, indicating that RGE blocks the histamine receptor type 1/TRPV1 pathway in sensory neurons, which is responsible for histamine-dependent itch sensation. Conclusion: The current study found for the first time that RGE effectively blocks histamine-induced itch in peripheral sensory neurons. We believe that the current results will provide an insight on itch transmission and will be helpful in understanding how RGE exerts its antipruritic effects.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.6
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• pp.511-519
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• 2001

Nimopidine, one of dihydropyridine derivatives, has been widely used to pharmacologically identify L-type Ca currents. In this study, it was tested if nimodipine is a selective blocker for L-type Ca currents in sensory neurons and heterologous system. In mouse dorsal root ganglion neurons (DRG), low concentrations of nimodipine $(<10\;{\mu}M),$ mainly targeting L-type Ca currents, blocked high-voltage-activated calcium channel currents by ${\sim}38%.$ Interestingly, high concentrations of nimodipine $(>10\;{\mu}M)$ further reduced the 'residual' currents in DRG neurons from ${\alpha}_{1E}$ knock-out mice, after blocking L-, N- and P/Q-type Ca currents with $10\;{\mu}M$ nimodipine, $1\;{\mu}M\;{\omega}-conotoxin$ GVIA and 200 nM ${\omega-agatoxin$ IVA, indicating inhibitory effects of nimodipine on R-type Ca currents. Nimodipine $(>10\;{\mu}M)$ also produced the inhibition of both low-voltage-activated calcium channel currents in DRG neurons and ${\alpha}_{1B}\;and\;{\alpha}_{1E}$ subunit based Ca channel currents in heterologous system. These results suggest that higher nimodipine $(>10\;{\mu}M)$ is not necessarily selective for L-type Ca currents. While care should be taken in using nimodipine for pharmacologically defining L-type Ca currents from native macroscopic Ca currents, nimodipine $(>10\;{\mu}M)$ could be a useful pharmacological tool for characterizing R-type Ca currents when combined with toxins blocking other types of Ca channels.

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.190.1-190.1
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• 2001