• The Korean Journal of Physiology
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• 제28권2호
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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.

• The Korean Journal of Physiology
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• 제23권2호
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• pp.409-420
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• 1989

Extracellular recordings were made from the spinal neurons in the lumbar enlargement of 16 cats before and during electrical stimulation of the radial nerve ipsilaterally and contralaterally. Only neurons activated by remote nerve stimulation (RNS) were included in sample. All the cell classes of spinal neurons which received afferents message from the skin and/or muscles were activated by RNS except LT cells. Approximately three quaters of cells activated by RNS had an inhibitory receptive field (RF) on the ipsilateral hindlimb and two thirds of RNS-activated neurons showed spontaneous activity. The most of these RNS-activated cells seemed to be in deep dorsal horn and in ventral horn as well. Stimulation of contralateral radial nerve produced activation of spinal neurons almost same degree as by ipsilateral nerve stimulation. The optimal stimulation parameters of radial nerve for activation of spinal cells were 5Hz-0.5 msec-2V while threshold stimulus for activation was approximately 0.18 V. Following close intra-arterial injection of $K^+$ ion excitability of RNS-activated neuron was increased in 4 of 8 cells whereas it was decreased in 2 of 8 cells. The results indicate that there are some spinal neurons in the lumbar enlargement of cats that can be activated by forelimb afferent $(A{\beta}\;&\;A{\delta})$ inputs.

• 동의신경정신과학회지
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• 제11권1호
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• pp.1-18
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• 2000

To study the effects of Ramulus et Uncus Uncariae (REUU) on oxygen free radical-mediated damage by hydrogen peroxide $(H_{2}O_{2})$ on cultured spinal sensory neurons, in vitro assays such as MTT assay, NR assay, neurofilament enzymeimmuno assay (EIA), sulforhodamine B (SRB) assay, assay for lactate dehydrogenase (LDH) activity and assay for lipid peroxidation were used in cultured spinal dorsal root ganglion neurons derived from mice, Spinal dorsal root ganglion neurons were cultured in media containing various concentrations of $H_{2}O_{2}$ for 5 hours, after which the neurotoxic effect of $H_{2}O_{2}$ was measured by in vitro assay. The protective effect of the herb extract, Ramulus et Uncus Uncariae (REUU) against H2O2-induced neurotoxicity was also examined. The results are as follows. 1. In NR assay and MTT assay, $H_{2}O_{2}$ significantly decreased the cell viability of cultured mouse spinal dorsal root ganglion neurons according to exposure concentration in these cultures. An additional time course study was done on these cultures. 2. Cultured spinal dorsal root ganglion neurons which were exposed to various concentrations of $H_{2}O_{2}$ showed a quantitative decrease of neuronal cells by EIA and of total protein by sulforhodamine B (SRB) assay, while they showed an increase of both lipid peroxidation and LDH activity. 3. The effect of Ramulus et Uncus Uncariae (REUU) on $H_{2}O_{2}$ induced neurotoxicity showed a quantitative increase in both neurofilament and total protein, but showed a decrease of lipid peroxidation and LDH activity. These results suggest that $H_{2}O_{2}$ has a neurotoxic effect on cultured spinal dorsal root ganglion neurons from mice and that the herb extract, Ramulus et Uncus Uncariae (REUU), was very effective in protecting $H_{2}O_{2}$ induced neurotoxicity by decreasing lipid peroxidation and LDH activity.

• 대한한방내과학회지
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• 제22권4호
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• pp.557-565
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• 2001

Objectives : This study was carried out to examine toxic effect of Sintongchukeo-tang on cultured mouse spinal sensory neurons inhibited by neurotoxicity induced by hydrogen peroxide. Methods : MTT assay, NR assay, LDH and neurofilament assay were performed after spinal sensory neurons were preincubater with various concentrations of Sintongchukeo-tang water extract before treatment of cells with hydrogen peroxide. Results : Hydrogen peroxide induced ceil degeneration such as the decrease of cell viability was measured by MTT and NR assay in the cultured mouse spinal sensory neurons. Sintongchukeo-tang water extract was effective in the decrease of LDH activities of neurons produced by hydrogen peroxide. Sintongchukeo-tang water extract was effective in the increase of amount of neurofilaments damaged by hydrogen peroxide. Conclusions : From the above results, it is suggested that hydrogen peroxide induces the inhibition of cell viability in cultured mouse spinal sensory neurons and Sintongchukeo-tang water extract was effective in cultured neurons damaged by hydrogen peroxide.

• 대한약리학회지
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• 제32권2호
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• pp.283-292
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• 1996

The spinal dorsal horn is the area where primary afferent fibers terminate and cutaneous sensory information is processed. A number of putative neurotransmitter substances, including excitatory and inhibitory amino acids and peptides, are present in this region. In this study, single neurons of the spinal dorsal horn were acutely isolated and the properties of whole cell current and responses to excitatory and inhibitory neurotransmitters were studied by patch clamp technique. Transverse slice ($(300{\mu}m$) of lumbar spinal cords from young rats$(7{\sim}14\;days)$ were sequentially treated with two pretenses(pronase 0.75 mg/ml and thermolysin 0.75 mg/ml), then single neurons were mechanically dissociated. These neurons showed near-intact morphology such as multipolar, ellipsoidal and bipolar, and pyramidal cells and we recorded the typical whole cell currents of $K^+$, $Ca^{2+}$ and ligand-operated channels from these neurons. Glutamate $(30{\mu}M)$ and N-methyl-D-aspartate(NMDA, $30{\mu}M)$ induced inward currents of $117{\pm}12.4$ pA(n=5) and $49{\pm}6.9$ pA(n=3), respectively. Glycine $(1{\mu}M)$ potentiated glutamate-induced currents $4{\sim}5$ times and NMDA-induced currents $8{\sim}10$ times. In addition, glycine $(30{\mu}M)$ induced Inward current ($31{\pm}6.1$ nA, n=2), which was rapidly desensitized after the peak to a new steady-state level. However, the inward currents induced by ${\gamma}-amino$ butyric acid(GABA, $1{\mu}M$) decreased continuously after the peak($226{\pm}41.6$ pA, n=3) under the similar experimental condition. The ionic currents and pharmacological responses of isolated neurons in this work were similar to those observed in vivo or in vitro spinal cord slice, indicating that acutely isolated neurons could be effectively used for further pharmacological studies.

• Journal of Acupuncture Research
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• 제17권2호
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• pp.95-117
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• 2000

The purpose of this morphological studies was to investigate the relation between the meridian, acupoints and viscera using neuroanatomical tracers. The common locations of the spinal ganglia, sympathetic chain ganglia, spinal cord and brain projecting to the large intestine meridian were observed following injection of transganglionic tracer, WGA-HRP and transsynaptic neurotropic virus, pseudorabies virus(PRV), Bartha strain(Ba) and PRV-Ba-Gal (Galactosidase)) into the the large intestine(cecum, colon and rectum), ST37 and LI4. After survival times of 96 hours following injection into the thirty rats with WGA-HRP, PRV-Ba and PRV-Ba-Gal. They were perfused, and their spinal ganglia, sympathetic chain ganglia, spinal cord and brain were frozen sectioned($30{\mu}m$). These sections were stained by HRP and X-gal histochemical and PRV immunohistochemical staining method, and observed with a light microscope. The results were as follows : 1. WGA-HRP labeled neurons innervating the large intestine were observed bilaterally within the T13-L4 sympathetic chain ganglia, and T9-11 spinal ganglia. WGA-HRP labeled neurons innervating ST37 were observed within the L3-5 sympathetic chain ganglia, and L2-4 spinal ganglia. WGA-HRP labeled neurons innervating LI4 were observed in the middle cervical ganglion and stellate ganglion, and C5-8 spinal ganglia. 2. In spinal cord, PRV-Ba labeled neurons projecting to the large intestine, ST37 and LI4 were found in thoracic, lumbar and sacral spinal segments. Densely labeled areas of each spinal cord segment were founded in lamina N, V, VII(intermediolateral nucleus), Ⅸ, X and dorsal nucleus. 3. In medulla oblongata, PRV-Ba and PRV-Ba-Gal labeled neurons projecting to the large intestine, ST37 and LI4 were commonly found in the A1 noradrenalin cells/C1 adrenalin cells/caudoventrolateral reticular nucleus, dorsal motor nucleus of vagus nerve, nucleus tractus solitarius, raphe obscurus nucleus, raphe pallidus nucleus, raphe magnus nucleus and gigantocellular nucleus. 4. In pons, PRV-Ba and PRV-Ba-Gal labeled neurons were commonly found in locus coeruleus, Kolliker-Fuse nucieus and A5 cell group. 5. In midbrain, PRV-Ba and PRV-Ba-Gal labeled neurons were commonly found in central gray matter. 6. In diencephalon, PRV-Ba and PRV-Ba-Gal labeled neurons were commonly found in paraventricular hypothalamic nucleus. These results suggest that PRV-Ba and PRV-Ba-Gal labeled common areas projecting to the large intestine may be correlated to that of the large intestine meridian, ST37 and LI4. Especially, These morphological results provide that interrelationship of meridian-acupoints -viscera may be related to the central autonomic pathways.

• 약학회지
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• 제41권1호
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• pp.99-104
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• 1997

In order to elucidate the cytotoxic effect of oxygen radicals on cultured spinal dorsal root ganglion(DRG) neurons derived from mouse. the neurotoxic effect of oxygen radicals w as examined after cultured DRG neurons were exposed to xanthine oxidase(XO) and hypoxanthine(HX)-oxygen radical generating system. In addition. neuroprotective effect of epidermal growth factor(EGF) against oxidant-induced neurotoxicity was also evaluated in these cultures. The results were, as follows: 1. Lethal concentration 50(LC$_{50}$) was 35mU/ml XO and 0.1mM HX in cultured DRG neurons. 2. Oxygen radicals induced the morphological changes such as the decrease of cell number and loss of neurites in these cultures. 3. EGF increased the cell viability and neurofilament in neurons damaged by oxygen radicals. From above the results, it is suggested that oxygen radicals have a cytotoxic effect on cultured DRG neurons of neonatal mouse and selective neurotrophic factors such as EGF are, effective, in blocking the neurotoxicity induced by oxygen radicals in cultured spinal DRG neurons.

• 동의생리병리학회지
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• 제23권4호
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• pp.805-817
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• 2009

This study was to investigate central localization of neurons projecting to the urinary bladder and urinary bladder-related acupoints(Wijung, $BL_{40}$) and neurons of immunoreactive to hormones and hormone receptors regulating urinary bladder function by using peudorabies virus(PRV). In this experiment, Bartha's strain of pseudorabies virus was used in rats to trace central localization of urinary bladder-related neurons and urinary bladder-related acupoints($BL_{40}$) which can regulate urinary system. PRV was injected into the urinary bladder and acupoints($BL_{40}$) related urinary system. After six days survival of rats, mainly common labeled neurons projecting to the urinary bladder and urinary bladder-related acupoints were identified in spinal cord, medulla, pons and diencephalon by PRV immunohistochemical staining method. First-order PRV labeled neurons projecting to urinary bladder and urinary bladder-related acupoints were found in the cervical, thoracic, lumbar and sacral spinal cord. Commonly labeled preganglionic neurons were labeled in the lumbosacral spinal cord and thoracic spinal cord. They were found in the lateral horn area(sacral parasympathetic nucleus and intermediolateral nucleus), lamina V-X, intermediomedial nucleus and dorsal column area. The area of sensory neurons projecting to urinary bladder and Wijung($BL_{40}$) was L5-S2 spinal ganglia and T12-L1 spinal ganglia, respectively. In the brainstem, the neurons were labeled most evidently and consistently in the nucleus of tractus solitarius, area postrema, dorsal motor nucleus of vagus nerve, reticular nucleus, raphe nuclei(obscurus, magnus and pallidus), C3 adrenalin cells, parapyramidal area(lateral paragigantocellular nucleus), locus coeruleus, subcoeruleus nucleus, A5 cell group, Barrington's nucleus and periaqueductal gray matter. In the diencephalon, PRV labeled neurons were marked mostly in the paraventricular nucleus and a few ones were in the lateral hypothalamic nucleus, posterior hypothalamic nucleus, ventromedial hypothalamic nucleus, arcuate nucleus, median eminence, perifornical nucleus, periventricular nucleus and suprachiasmatic nucleus. In cerebral cortex, PRV labeled neurons were marked mostly in the frontal cortex, 1,2 area, hind limb area, agranular insular cortex. Immunoreactive neurons to Corticotropin releasiing factor(CRF), Corticotropin releasiing factor-receptor(CRF-R), c-fos and serotonin were a part of labeled areas among the virus-labeled neurons of urinary bladder and Wijung($BL_{40}$). The commonly labeled areas were nucleus tractus solitarius, area postrema, reticular nucleus, raphe nuclei(obscurus, magnus and pallidus), locus coeruleus, A5 cell group, Barrington,s nucleus, arcuate nucleus, paraventricular nucleus, frontal cortex 1, 2 area, hind limb, and perirhinal(agranular insular) cortex. These results suggest that overlapped CNS locations are related with autonomic nuclei which regulate the functions of urinary bladder-relate organs and it was revealed by tracing PRV labeled neurons projecting urinary bladder and urinary bladder-related acupoints. These commonly labeled areas often overlap with the neurons connected with hormones and hormone receptors related to urination.

• 대한물리치료과학회지
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• 제8권2호
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• pp.1005-1013
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• 2001

The present study was designed to investigate the effect of low power GaAlAs laser on spinal Fos expression related to the anti-nociceptive effect of laser stimulation. Low power GaAlAs laser was applied to either acupoint or non-acupoint for 2 hour under light inhalation anesthesia. Spinal Fos expression in the dorsal horn was compared to that obtained in inhalation anesthesia control group. Furthermore, we analyzed the effect of the local treatment of lidocaine on the spinal Fos expression evoked by low power GaAlAs laser stimulation. The results were summarized as follows: 1. In the normal animals, only a few Fos like immunoreactive(Fos-IR) neurons were evident in the lumbar spinal cord dorsal horn. Similarly, following prolonged inhalation anesthesia, Fos-IR neurons were absent in the dorsal horn of the lumbar spinal cord. In animals treated with laser stimulation, Fos immunoreactive neurons were increased mainly in the medial half of ipsilateral laminae I-III at lumbar segments L3-5. These findings directly indicated that prolonged anesthesia used in this study did not affect the Fos expression in the spinal cord dorsal horn of intact animals and low power laser stimulation dramatically produced Fos expression in the spinal cord laminae that are related to the anti-nociceptive effect of laser stimulation. 2. In acupoint stimulated animals, 10mW of laser stimulation, not 3mW and 6mW intensity, significantly increased the number of Fos immunoreactive neurons in the spinal dorsal horn(p<0.05). However, laser stimulation on acupoint more dramatically increased the number of Fos immunoreactive neurons in the spinal cord rather than laser stimulatin on non acupoint. These result suggested that laser stimulatin on acupoint was more effective treatment to activate the spinal neuron than non acupoint stimulation. 3. The local treatment of lidocaine totally suppressed the activity of spinal neurons that were induced by lower power 1aser stimulation. These data indicated that the anti-nociceptive effect of laser stimulation was absolutely dependent upon the peripheral nerve activity in the stimulated location. In conclusion, these data indicate that 10mW of low power laser stimulation into acupoint is capable of inducing the spinal Fos expression in the dorsal horn related to the anti-nociceptive effect of laser stimulation, Furthermore, the induction of spinal Fos expression was totally related to the peripheral nerve activity in the laser stimulated area.

• 대한수의학회지
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• 제43권1호
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• pp.11-24
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• 2003

This experimental studies was to investigate the location of PNS and CNS labeled neurons following injection of 2% WGA-HRP and pseudorabies virus (PRY), Bartha strain, into the ductus deferens of rats. After survival times 4-5 days following injection of 2% WGA-HRP and PRV, the rats were perfused, and their brain, spinal cord, sympathetic ganglia and spinal ganglia were frozen sectioned ($30{\mu}m$). These sections were stained by HRP histochemical and PRY inummohistochemical staining methods, and observed with light microscope. The results were as follows ; 1. The location of sympathetic ganglia projecting to the ductus deferens were observed in pelvic ganglion, inferior mesenteric ganglion and L1-6 lwnbar sympathetic ganglia. 2. The location of spinal ganglia projecting to the ductus deferens were observed in T13-L6 spinal ganglia. 3. The PRY labeled neurons projecting to the ductus deferens were observed in lateral spinal nucleus, lamina I, II and X of cervical segments. In thoracic segments, PRY labeled neurons were observed in dorsomedial part of lamina I, II and III, and dorsolateral part of lamina IV and V. Densely labeled neurons were observed in intermediolateral nucleus. In first lumbar segment, labeled neurons were observed in intermediolateral nucleus and dorsal commisural nucleus. In sixth lumbar segment and sacral segments, dense labeled neurons were observed in sacral parasympathetic nuc., lamina IX and X. 4. In the medulla oblongata, PRV labeled neurons projecting to the ductus deferens were observed in the trigeminal spinal nuc., A1 noradrenalin cells/C1 adrenalin cells/caudoventrolateral reticular nuc., rostroventrolateral reticular nuc., area postrema, nuc. tractus solitarius, raphe obscurus nuc., raphe pallidus nuc., raphe magnus nuc., parapyramidal nuc., lateral reticular nuc., gigantocellular reticular nuc.. 5. In the pons, PRV labeled neurons projecting to the ductus deferens were ohserved in parabrachial nuc., Kolliker-Fuse nuc., locus cooruleus, subcooruleus nuc. and AS noradrenalin cells. 6. In midbrain, PRV labeled neurons projecting to the ductus deferens were observed in periaqueductal gray substance, substantia nigra and dorsal raphe nuc.. 7. In the diencephalon, PRV labeled neurons projecting to the ductus deferens were observed in paraventricular hypahalamic nuc., lateral hypothalamic nuc., retrochiasmatic nuc. and ventromedial hypothalamic nuc.. 8. In cerebrum, PRV labeled neurons projecting to the ductus deferens were observed in area 1 of parietal cortex. These results suggest that WGA-HRP labeled neurons of the spinal cord projecting to the rat ductus deferens might be the first-order neurons related to the viscero-somatic sensory and sympathetic postganglionic neurons, and PRV labeled neurons of the brain and spinal cord may be the second and third-order neurons response to the movement of smooth muscles in ductus deferens. 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 monitaing the internal environment. These observations provide evidence for previously unknown projections from ductus deferens to spinal cord and brain which may be play an important neuroanatornical basic evidence in the regulation of ductus deferens function.