• Journal of Ginseng Research
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• 제35권2호
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• pp.219-225
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• 2011

Korean red ginseng (KRG) is a valuable and important traditional medicine in East Asian countries and is currently used extensively for botanical products in the world. KRG has both stimulatory and inhibitory effects on the central nervous system (CNS) suggesting its complicated action mechanisms. The substantia gelatinosa (SG) neurons of the trigeminal subnucleus caudalis (Vc) are involved in orofacial nociceptive processing. Some studies reported that KRG has antinociceptive effects, but there are few reports of the functional studies of KRG on the SG neurons of the Vc. In this study, a whole cell patch clamp study was performed to examine the action mechanism of a KRG extract on the SG neurons of the Vc from juvenile mice. KRG induced short-lived and repeatable inward currents on all the SG neurons tested in the high chloride pipette solution. The KRG-induced inward currents were concentration dependent and were maintained in the presence of tetrodotoxin, a voltage gated $Na^+$ channel blocker. The KRG-induced inward currents were suppressed by 6-cyano-7-nitroquinoxaline-2,3-dione, a non-N-methyl-D-aspartate (NMDA) glutamate receptor antagonist and/or picrotoxin, a gamma-aminobutyric acid $(GABA)_A$ receptor antagonist. However, the inward currents were not suppressed by d,l-2-amino-5-phosphonopentanoic acid, an NMDA receptor antagonist. These results show that KRG has excitatory effects on the SG neurons of the Vc via the activation of non-NMDA glutamate receptor as well as an inhibitory effect by activation of the $GABA_A$ receptor, indicating the KRG has both stimulatory and inhibitory effects on the CNS. In addition, KRG may be a potential target for modulating orofacial pain processing.

• Bulletin of the Korean Chemical Society
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• 제34권6호
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• pp.1643-1650
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• 2013

A non linear QSAR model was constructed on a series of 57 xanthone and curcuminoide derivatives as ${\alpha}$-glucosidase inhibitors by back-propagation neural network method. The neural network architecture was optimized to obtain a three-layer neural network, composed of five descriptors, nine hidden neurons and one output neuron. A good predictive determination coefficient was obtained (${R^2}_{Pset}$ = 86.7%), the statistical results being better than those obtained with the same data set using a multiple regression analysis (MLR). As in the MLR model, the descriptor MATS7v weighted by Van der Waals volume was found as the most important independent variable on the ${\alpha}$-glucosidase inhibitory.

• 전자공학회논문지B
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• 제29B권11호
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• pp.85-92
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• 1992

In this paper we propose a diffusion neural network model. In this model, each excitatory and inhibitory neuron has the capability of diffusing external excitations. We show that this model can be used for the detection of intensity changes of an input image. The relations between the diffusion coefficient, the iteration number of diffusion, and the detected spatial frequency are analyzed. The calculation time is reduced than that of a LOG(a Laplacian of a Gaussian) method.

• The Korean Journal of Pain
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• 제11권1호
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• pp.23-29
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• 1998

Background: The present study was conducted to investigate effects of microinjection of bicuculline, GABA-A receptor antagonist, into the brain stem nuclei on the dorsal horn neuron responsiveness in rats with an experimental peripheral neuropathy. Methods: An experimental neuropathy was induced by a unilateral ligation of L5~L6 spinal nerves of rats. After 2~3 weeks after the surgery, single-unit recording was made from wide dynamic range (WDR) neurons in the spinal cord dorsal horn. Results: Responses of WDR neurons to both noxious and innocuous mechanical stimuli applied to the somatic receptive fields were enhanced on the nerve injured side. These enhanced responsiveness of WDR neurons were suppressed by microinjection of bicuculline into periaqueductal gray(PAG) or nucleus reticularis gigantocellularis(Gi). A similar suppression was also observed when morphine was microinjected into PAG or Gi. Suppressive action by Gi-bicuculline was reversed by naloxonazine, ${\mu}$-opioid receptor antagonist, microinjected into PAG whereas PAG-bicuculline induced suppression was not affected by naloxonazine injection into Gi. Gi-bicuculline induced suppression were reversed by a transection of dorsolateral funiculus(DLF) of the spinal cord. Conclusions: The results suggest that endogenous opioids, via acting on GABAergic interneurons in PAG and Gi, may be involved in the control of neuropathic pain by activating the descending inhibitory pathways that project to the spinal dorsal horn through DLF to inhibit the responsiveness of WDR neurons.

• Journal of Genetic Medicine
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• 제2권2호
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• pp.53-57
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• 1998

Spinal muscular atrophy (SMA) type I is a common severe autosomal recessive inherited neuromuscular disorder that has been mapped to chromosome 5q11.2-13.3. The survival motor neuron (SMN) gene, a candidate gene, is known to be deleted in 96% of patients with SMA type I. Presently, PCR and single strand conformation polymorphism (PCR-SSCP) analyses have been made possible for application to both archival slides and paraffin-embedded tissues. Archival materials represent valuable DNA resources for genetic diagnosis. We applied these methods for the identification of SMN gene of SMA type I in archival specimens for the prenatal diagnosis. In this study, we performed the prenatal diagnosis with chorionic villus sampling (CVS) cells on two women who had experienced neonatal death of SMA type I. DNA extraction was done from archival slide and tissue materials and PEP-PCR was performed using CVS cells. In order to identify common deletion region of SMN and neuronal apoptosis-inhibitory protein (NAIP) genes, cold PCR-SSCP and PCR-restriction site assay were carried out. Case 1 had deletions of the exons 7 and 8, and case 2 had exon 7 only on the telomeric SMN gene. Both cases were found to be normal on NAIP gene. These results were the same for both CVS and archival biopsied specimens. In both cases, the fetuses were, therefore, predicted to be at very high risk of being affected and the pregnancy were terminated. These data clearly demonstrate that archival slide and paraffin-embedded tissues can be a valuable source of DNA when the prenatal genetic diagnosis is needed in case any source for genetic analysis is not readily available due to previous death of the fetus or neonate.

• 한방재활의학과학회지
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• 제21권4호
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• pp.13-22
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• 2011

Objectives : This Study was performed to evaluate the effects of Scutellariae Radix(SR) water-extract on the tissue and neuronal apoptosis of the spinal cord injury(SCI). Methods: SCI was induced by mechanical contusion following laminectomy of 10th thoracic vertebra in Sprague-Dawley rats. SR was orally given once a day for 7 days after SCI. Neuronal apoptosis was examined with terminal deoxynucleotidyl transferase-mediated dUTPnick-end labeling(TUNEL) assay. Bax (Bcl-2-asociated X protein), Bcl-2(B-cell blastoma 2), c-Fos(FBJ osteosarcoma oncogene) expressions were examined using immuno-histochemistry. Individual TUNEL and immuno-labeled cells expressing Bax, Bcl-2 and c-Fos were counted on the same level in peri-damaged region and in ventral horn. Results: 1. SR significantly reduced number of TUNEL labeled apoptotic cells induced by the spinal cord contusion injury. 2. SR significantly reduced Bax positive cells expression on the motor neuron in the ventral horn induced by the spinal cord contusion injury. 3. SR strengthened Bcl-2 expression on the motor neuron in the ventral horn induced by the spinal cord contusion injury. 4. SR reduced c-Fos expression on the motor neuron in the ventral horn induced by the spinal cord contusion injury. Conclusions : These results suggest that SR plays an inhibitory role against neuronal apoptosis and has significant effects for locomotor disfunction induced by SCI.

• 대한한의학회지
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• 제25권4호
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• pp.95-107
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• 2004

Objective : The inappropriate or excessive apoptosis has been known to be associated with neurodegenerative disorders including intracranial hemorrhage(ICH). Paeoniae radix, in traditional Korean medicine, has played its role as blood­nourisher and yin-astringent. In the present study, the effect of Paeoniae radix on the inhibition of neurodegeneration in the brain of rats after artificial ICH and on the resulting apoptosis was investigated. Methods : 30 rats were divided into 6 equal groups ; the sham-operation group, the hemorrhage-induction group, the hemorrhage-induction with 10, 50, 100, and 200 mg/kg Paeoniae radix-treated group, respectively. Stereotactic surgery was performed and collagenase was infused to induce ICH in the region of CA1 of hippocampus of rats. The sham group took only saline infusion. For 7 days after the surgery, 4 testing groups had intraperitoneal injections of Paeoniae radix extract. The step-down inhibitory avoidance task, measurement of neurodegeneration degree in the CA1 region of the hippocampus, and detection of caspase-3 and newly generated cells in the dentate gyrus were done after animal sacrifice. Results : Rats receiving Paeoniae radix extract showed increased latency time in the inhibitory avoidance task. The extension of neuron-deprived areas in the CA1 region was significantly suppressed in the Paeonia treated groups. Also expressions of caspase-3 in the CA1 region and cortex were significantly inhibited in the Paeonia treated groups. The cell proliferation was evaluated by means of BrdU methods and proved to be decreased in the Paeonia treated groups. Conclusion : These results suggest that Paeoniae radix has potential to suppress short-tenn memory loss after devastating neurologic accidents. Also it was proved that Paeoniae radix has a neuroprotective effect and alleviates central nervous complications following intracerebral hemorrhage. Furthermore, it may imply that this medicinal plant can be widely used for vascular dementia and other neurodegenerative disorders.

• 대한소아치과학회지
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• 제25권4호
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• pp.671-682
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• 1998

Electrophysiological phenomena of pyramidal cells in the CA1 area of the dorsal hippocampus were recorded from and filled with neurobiotin in anesthetized rats. The electropharmacological properties of membrane as well as the cellular-synaptic generation of rhythmic slow activity (theta) were examined. The intracellular response characteristics of these pyramidal cells were distinctly different from responses of interneurons. Pyramidal cells had a high resting membrane potential, a low input resistance, and a large amplitude action potential. A afterhyperpolarization was followed a single action potential. Most of pyramidal cells did not display a spontaneous firing. Pyramidal cells displayed weak inward rectification and anodal break excitation. The slope of the frequency-current relation was 53.4 Hz/nA for the first interspike interval and 15.9 Hz/nA for the last intervals, suggesting the presence of spike frequency adaptation. Neurobiotin-filled neurons showed pyramidal morphology. Cells were generally bipolar dendritc processes ramifying in stratum lacunosum-moleculare, radiatum, and oriens. Commissural stimulation discharged pyramidal cells, followed by excitatory and inhibitory postsynaptic potentials (EPSPs and IPSPs). The frequency of theta-related membrane potential oscillation was voltage-independent in pyramidal neurons. At strong depolarization levels (less than 30 mV) pyramidal cells emitted sodium spike oscillation, phase-locked to theta. The observations provide direct evidence that theta-related rhythmic hyperpolarization of principal cells is brought by the rhythmically discharging interneurons. Furthermore, the findings in which interneurons were also paced by rhythmic inhibitory postsynaptic potentials during theta suggest that they were periodically hyperpolarized by their GABAergic septal afferents.

• Biomolecules & Therapeutics
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• 제18권1호
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• pp.48-55
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• 2010

Neural progenitor cells (NPCs) differentiate into astrocytes, neurons and oligodendrocytes, which is controlled by various factors in brain. Recent evidences suggest that small molecules modulating the proliferation and differentiation of NPCs may have therapeutic value as well as the potential use as chemical probes. Phylligenin is a lignan with anti-inflammatory activity that is isolated from the fruits of Forsythia koreana. We investigated effects of phylligenin on proliferation and differentiation of NPCs. Treatment of phylligenin decreased the number of proliferating NPCs in culture without effects on the differentiation and survival of neural cells such as neurons and astrocytes. To examine the mechanism of the decreased NPCs number, we performed cell cycle analysis. Proliferation of NPCs was decreased via G1-S transition block by phylligenin treatment, and it was mediated by the increase of p21 level. However, phylligenin did not induce apoptosis of NPCs as determined by TUNEL assay and PARP cleavage. We also found that viability of glioma cell lines such as C6 and U87MG glioma cells, but not that of primary neuron and astrocyte, was inhibited by phylligenin. These results suggest that phylligenin selectively inhibits proliferation of rapidly growing cells such as neural stem cells and glioma cells. Given that the possible role of brain tumor stem cells in the pathology of brain cancers, the inhibitory effects of phylligenin might be useful in the development of new therapeutic agents against brain cancers.

• Korean Journal of Acupuncture
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• 제26권3호
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• pp.27-42
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• 2009

Objectives : The vestibular system detects head movement and serve to regulate and maintain the equilibrium and orientation of the body. It is known that the vestibular imbalance leads to vestibular symptoms such as nausea, vomiting, vertigo and postural disturbance. The objectives of the present study were to examine a modification of the dynamic activities of medial vestibular nucleus (MVN) neurons following electroacupuncture (EA) of GB43 (Hyepgye). Methods : In Sprague-Dawley rats weighing $250{\sim}300g$, dynamic responses induced by sinusoidal whole body rotation about vertical axis at 0.2 Hz were observed in MVN of rats during EA of GB43 (Hyepgye) with 0.2 ms, 40 Hz and $600{\pm}200{\mu}A$. Also, expression of cFos protein was observed 2 hours after EA for 30 mins. Results : In dynamic response of vestibular neuron, the excitatory or inhibitory responses of gain were predominant in the ipsilateral MVN neurons during EA but not predominant in the contralateral MVN. Most neurons showing decreased gain were classified to inhibitory responses of spontaneous firing discharge during EA and ones showing increased gain were classified to excitatory response of spontaneous firing discharge during EA. Also, EA of the left GB43 (Hyepgye) for 30 mins produced the expression of cFos protein in MVN, inferior olive (IO) and solitary tract nuclei (SOL). Spatial expressions of cFos protein were predominant in the contralateral MVN, ipsilateral IO and bilateral SOL. Conclusion : These results suggest that the excitability of MVN neurons was influenced by EA of GB43 (Hyepgye) and EA may be related to the convergence on MVN.