• The Korean Journal of Physiology and Pharmacology
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• v.4 no.1
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• pp.15-24
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• 2000

Although nociceptive informations are thought to be processed via different neural mechanisms depending on the types of stimuli, sufficient data have not been accumulated yet. We performed a series of experiments to elucidate the possible neural mechanisms as to chemical stimuli such as formalin, capsaicin and ATP. Single unit activity of wide dynamic range (WDR) neurons and high threshold cells were recorded extracellularly from the lumbosacral enlargement of cat spinal cord before and after chemical stimulation to its receptive field (RF). Each chemical substance - formalin $(20{\mu}l,\;4%),$ capsaicin (33 mM) or Mg-ATP (5 mM)- was injected intradermally into the RFs and then the changes in the spontaneous activity, mechanical threshold and responses to the peripheral mechanical stimuli were observed. In many cases, intradermal injection of formalin (5/11) and capsaicin (8/11) resulted in increase of the spontaneous activity with a biphasic pattern, whereas ATP (8/8) only showed initial responses. Time courses of the biphasic pattern, especially the late response, differed between formalin and capsaicin experiments. One hour after injection of each chemical (formalin, capsaicin, or ATP), the responses of the dorsal horn neurons to mechanical stimuli increased at large and the RFs were expended, suggesting development of hypersensitization (formalin 6/10, capsaicin 8/11, and ATP 15/19, respectively). These results are suggested that formalin stimulates peripheral nociceptor, local inflammation and involvement of central sensitization, capsaicin induces central sensitization as well as affects the peripheral C-polymodal nociceptors and neurogenic inflammation, and ATP directly stimulates peripheral nociceptors.

• The Korean Journal of Physiology and Pharmacology
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• v.23 no.2
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• pp.141-150
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• 2019

Despite increased evidence of bio-activity following far-infrared (FIR) radiation, susceptibility of cell signaling to FIR radiation-induced homeostasis is poorly understood. To observe the effects of FIR radiation, FIR-radiated materials-coated fabric was put on experimental rats or applied to L6 cells, and microarray analysis, quantitative real-time polymerase chain reaction, and wound healing assays were performed. Microarray analysis revealed that messenger RNA expressions of rat muscle were stimulated by FIR radiation in a dose-dependent manner in amount of 10% and 30% materials-coated. In 30% group, 1,473 differentially expressed genes were identified (fold change [FC] > 1.5), and 218 genes were significantly regulated (FC > 1.5 and p < 0.05). Microarray analysis showed that extracellular matrix (ECM)-receptor interaction, focal adhesion, and cell migration-related pathways were significantly stimulated in rat muscle. ECM and platelet-derived growth factor (PDGF)-mediated cell migration-related genes were increased. And, results showed that the relative gene expression of actin beta was increased. FIR radiation also stimulated actin subunit and actin-related genes. We observed that wound healing was certainly promoted by FIR radiation over 48 h in L6 cells. Therefore, we suggest that FIR radiation can penetrate the body and stimulate PDGF-mediated cell migration through ECM-integrin signaling in rats.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.3
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• pp.153-159
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• 2004

The interstitial cells of Cajal (ICCs) are the pacemaker cells in gastrointestinal tract and generate electrical rhythmicity in gastrointestinal muscles. Therefore, ICC may be modulated by endogenous agents such as neurotransmitter, hormones, and prostaglandins (PGs). In the present study, we investigated the effects of prostaglandins, especially $PGE_2$, on pacemaker currents in cultured ICCs from murine small intestine by using whole-cell patch clamp techniques. ICCs generated spontaneous slow waves under voltage-clamp conditions and showed a mean amplitude of $-452{\pm}39\;pA$ and frequency of $18{\pm}2$ cycles/min (n=6). Treatments of the cells with $PGE_2$ $(1\;{\mu}M)$ decreased both the frequency and amplitude of the pacemaker currents and increased the resting currents in the outward direction. $PGE_2$ had only inhibitory effects on pacemaker currents and this inhibitory effect was dose-dependent. For characterization of specific membrane EP receptor subtypes, involved in the effects of $PGE_2$ on pacemaker currents in ICCs, EP receptor agonists were used: Butaprost $(1\;{\mu}M)$, $EP_2$ receptor agonist, reduced the spontaneous inward current frequency and amplitude in cultured ICCs (n=5). However sulprostone $(1\;{\mu}M)$, a mixed $EP_1$ and $EP_3$ agonist, had no effects on the frequency, amplitude and resting currents of pacemaker currents (n=5). SQ-22536 (an inhibitor of adenylate cyclase; $100\;{\mu}M$) and ODQ (an inhibitor of guanylate cyclase; $100\;{\mu}M$) had no effects on $PGE_2$ actions of pacemaker currents. These observations indicate that $PGE_2$ alter directly the pacemaker currents in ICCs, and that the $PGE_2$ receptor subtypes involved are the $EP_2$ receptor, independent of cyclic AMP- and GMP-dependent pathway.

• Journal of Oriental Physiology
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• v.14 no.2 s.20
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• pp.199-208
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• 1999

As the average life span have been lengthened and the rate of senile population have been raised, chronic degenerative diseases incident to aging has been increased rapidly and become a social problem. With this social background, recently, the facts that oxygen radicals(OR) have toxic effects on Central Nervous System and Peripheral Nervous System and cause neuropathy such as Parkinson's Disease, Alzheimer Disease have been turned out, and accordingly lots of studies on the mechanism of the toxic effects of OR on nerves, the diseases caused by OR and the approaches to curing the diseases have been made. The purpose of this study is to examine the toxic effects caused by Glucose Oxidase(GO) and the effects of herbal extracts such as Chilbokyeum(CBY) on the treatment of the toxic effects. For this purpose, experiments with the cultured cell from the cerebrums of new born mice were done. The results of these experiments were as follows. 1. GO, a oxygen radical, decreased the survival rate of the cultured cells on NR assay and MTT assay 2. GO, a oxygen radical, increased lipid peroxidation and the amount of LDH. 3. CBY have efficacy of decreasing lipid peroxidation. 4. CBY have efficacy of decreasing the amount of LOH. From the above results, It is concluded that Chilbokyeum has marked efficacy as a treatment for the damages caused in the GO-mediated oxidative process. And Chilbokyeum is thought to have certain pharmacological effects on controlling over aging and treating Dementia. Further clinical study of this pharmacological effects of Chilbokyeum should be complemented.

• Journal of Photoscience
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• v.9 no.2
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• pp.391-393
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• 2002

Effects of illumination with xenon or sulfur lamp on growth of tomato seedlings were studied. Results showed no obvious differences in net photosynthetic rate and apparent quantum efficiency. In comparison with xenon lamp, illumination with sulfur lamp slightly reduced ChI a and ChI b content in leaves, relatively shortened epicotyl and hypocotyl length, but significantly increased anthocyanin content of leaves and promoted root growth of tomato seedling plants.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2005.10a
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• pp.91-91
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• 2005

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2005.10a
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• pp.91-91
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• 2005

• Proceedings of the Ginseng society Conference
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• 2004.12a
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• pp.57-57
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• 2004

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.879-879
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• 2005

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.864-864
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• 2005