• Title/Summary/Keyword: 이온통로

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Characterization of ion current induced by inhibitory and excitatory herbs in rat periaqueductal gray neuron (흰쥐 신경세포에서 억제성 및 흥분성 한약재가 유발한 이온전류의 특성)

  • Lee, Choong-Yeol;Cho, Sun-Hye;Seo, Jong-Eun;Han, Seung-Ho;Cho, Young-Wuk;Min, Byung-Il;Kim, Chang-Ju
    • The Journal of Korean Medicine
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    • v.19 no.2
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    • pp.450-467
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    • 1998
  • To research the characteristics of ion currents induced by inhibitory and excitatory herbs of oriental medicine, we used nystatin-perforated patch clamp technique under voltage clamp condition in periaqueductal gray neuron dissociated from Sprauge-Dawley rat, 10-15 days old. The results are as follows. 1. Ion current induced by $10mg/m{\ell}$ of Bupleuri Radix was inhibited $59.50{\pm}4.29%$ by $10^{-4}M$ bicuculline(p>0.01) but inhibition of $10.75{\pm}4.77%$ by $10^{-4}M$ tubocurarine and $4.75{\pm}4.23%$ by $10^{-4}M$ verapamil had no statistical significance(p>0.05). So ion current induced by Bupleuri Radix revealed only GABA induced $Cl^-$ current, not acetylcholine and $Ca^{2+}$ current. 2. Ion current induced by $20mg/m{\ell}$ of Coptidis Rhizoma was inhibited $47.20{\pm}7.88%$ by $10^{-4}M$ bicuculline(p<0.01) but $3.20{\pm}2.33%$ inhibition by $10^{-4}M$ tubocurarine and $1.00{\pm}1.00%$ inhibition by $10^{-4}M$ verapamil had no significance(p>0.05). So ion current induced by Coptidis Rhizoma revealed only GABA induced $Cl^-$ current, not acetylcholine and $Ca^{2+}$ current. 3. Ion current induced by $20mg/m{\ell}$ of Ecliptae Herba was inhibited $55.00{\pm}4.92%$ by $10^{-4}M$ bicuculline (p<0.01), and also inhibited $15.00{\pm}4.26%$ by $10^{-4}M$ tubocurarine(p<0.05), but inhibition of $6.00{\pm}3.03%$ by $10^{-4}M$ verapamil had no significance(p>0.05). So ion current induced by Ecliptae Herba showed GABA activated $Cl^-$ current and acetylcholine activated cation current, not $Ca^{2+}$ current 4. Ion current induced by $5mg/m{\ell}$ of Liriopis Tuber was inhibited $15.20{\pm}4.57%$ by $10^{-4}M$ bicuculline<0.05) and also inhibited $14.00{\pm}3.00%$ by $10^{-4}M$ tubocurarine(p<0.05), but inhibition of $5.20{\pm}4.80%$ by $10^{-4}M$ verapamil had no significance(p>0.05). So ion current induced by Liriopis Tuber showed GABA. activated $Cl^-$ current and acetylcholine activated cation current, not $Ca^{2+}$ current. 5. Ion current induced by $5mg/m{\ell}$ of Aconiti Tuber was inhibited $97.00{\pm}1.34%$ by $10^{-4}M$ bicuculline(p<0.01), $80.00{\pm}9.83%$ by $10^{-4}M$ tubocurarine(p<0.01), and $24.00{\pm}6.18%$ by $10^{-4}M$ verapamil(p<0.05). So ion current induced by Aconiti Tuber revealed GABA activated $Cl^-$ current and acetylcholine activated cation current and $Ca^{2+}$ current. 6. Ion current induced by $10mg/m{\ell}$ of Zingiberis Rhizoma was inhibited $33.00{\pm}7.43%$ by $10^{-4}$ bicuculline(p<0.05), $10.20{\pm}1.83%$ by $10-^{-4}M$ tubocurarine(p<0.01), and $14.00{\pm}2.16%$ by $10^{-4}M$ verapamil(p<0.01) So ion current induced by Zingiberis Rhizoma revealed GABA activated $Cl^-$ current and acetylcholine activated cation outtent and $Ca^{2+}$ current. 7. Ion current induced by $10mg/m{\ell}$ of Boshniakiae Herba was inhibited $65.00{\pm}13.75%$ by $10^{-4}M$ bicuculline(p<0.05), $38.00{\pm}9.24%$ by $10^{-4}M$ tubocurarine(p<0.05), and $33.25{\pm}7.42%$ by $10^{-4}M$ verapamiHp<0.05). So ion current induced by Bpshniakiae Herba revealed GABA activated $Cl^-$ current and acetylcholine activated cation current and $Ca^{2+}$ current. These results suggest that a point of difference between inhibitory and excitatory herbs is existence of$Ca^{2+}$ current.

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Glutamate-and NMDA-induced calcium influx at synaptosomes and the difference of their actions (Glutamate와 NMDA에 의한 Synaptosome에서의 칼슘 유입과 이들의 작용의 차이)

  • Lee, Chung-Soo;Sim, Jae-Keon;Shin, Yong-Kyoo;Lee, Kwang-Soo
    • The Korean Journal of Pharmacology
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    • v.24 no.1
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    • pp.71-81
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    • 1988
  • Glutamate and aspartate may evoke an increase in membrane permeability to monovalent cations and $Ca^{++}$. However, it is uncertain whether $Ca^{++}$ influx is mediated by voltage dependent $Ca^{++}$ channels or by excitatory amino acid activated channels. In addition, the influences of excitatory amino acids on $Ca^{++}$ uptake by neuronal tissues as well as the responses of their actions to extracellular $Mg^{++}$ concentration are different. $K^{+}$ induced $Ca^{++}$ uptake by synaptosomes was dependent on extracellular $Mg^{++}$ up to 5 mM and at concentration of 10 mM, $Ca^{++}$ influx was rather reduced. In $Na^{+}$ rich media, glutamate-and aspartate-induced $Ca^{++}$ uptake was increased by $Mg^{++}$ in a dose independent manner. However, the response for NMDA was inhibited by $Mg^{++}$ at concentrations above 2 mM. $K^+$-and glutamate-induced $Ca^{++}$ influx s were inhibited by 2,4-dinitrophenol, chlorprom-azine and verapamil but not by tetraethylammonium chloride. Tetrodotoxin effectively inhibited the action of glutamate but did not affect that of $K^+$. The response for MNDA was inhibited by 2, 4-dinitrophenol and tetrodotoxin, slightly inhibited by verapamil, and not affected by tetraethylammonium chloride. In $Na^{++}$ rich medium, depolarizing action of glutamate, aspartate and MNDA on synaptosomes was not demonstrated, whereas these agents stimulated $Ca^{++}$ uptake and caused $Ca^{++}$ influx induced depolarization at mitochondria. On the other hand, the activities of synaptosomal ATPases were not affected by excitatory amino acids at 5 mM. The results suggest that glutamate or NMDA induced $Ca^{++}$ influx at synaptosomes exhibits different responses for extracellular $Mg^{++}$ Ex citatory amino acids induced $Ca^{++}$ influx at synaptosomes may be associated with increased permeability of membrane for $Na^{++}$ and $Ca^{++}$ except $K^{++}$ and membrane depolarization due to increased ionic permeability.

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Analgesic Effect of Grape Seed Proanthocyanidin Extract in Fibromyalgia Animal Model (섬유근통 동물 모델에서 포도씨 추출 proanthocyanidin의 진통 효과)

  • Mun, Hyun-Il;Kim, Seong-Ho;Jang, Tae-Jung;Moon, Il-Soo
    • Journal of Life Science
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    • v.20 no.4
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    • pp.496-502
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    • 2010
  • The acidic saline animal model of pain has been suggested to mimic fibromyalgia (FM). Oligomeric proanthocyanidin complexes (OPC) from grape seeds are known to act as an antioxidant. We studied the effects of OPC on the pain threshold in the acidic saline animal model of pain. The left gastrocnemius muscle was injected with $100\;{\mu}l$ of saline at pH 4.0 under brief isoflurane anesthesia on days 0 and 5. Control rats (n=5) received identical injections of physiological saline (pH 7.2) on the same schedule. Rats (n=10) with acidic saline injection were separated into two study subgroups. After measurement of pre-drug pain thresholds, rats were injected intraperitoneally with either saline or OPC 300 mg/kg. Paw withdrawal thresholds to pressure were again measured 60 min after intraperitoneal injection. Nociceptive thresholds were measured with a Dynamic Plantar Aesthesiometer by applying an increasing pressure to right or left hind paw until the rat withdrew the paw. Compared to baseline (day 0), acid injections produced mechanical hyper-responsiveness on day 7 (pre-drug) in these rats [p<0.05]. A potent antihyperalgesic effect was observed when rats were injected intraperitoneally with OPC 300 mg/kg [injected paw, p=0.001; contralateral paw, p=0.002]. OPC treatment decreased the expression of acid sensing ion channel 3 in the brain motor cortex area on immunohistochemical staining when OPC 300 mg/kg was administered intraperitoneally in the animal model of FM pain [p<0.05]. Further research is required to determine the efficacy of OPC treatments in FM pain in humans.

Study on the Thickness Effect of the Separator for Lithium Secondary Batteries (리튬이차전지용 분리막의 두께에 따른 특성 연구)

  • Kim, Sang Woo;Seok, Ji-Hoo;Kim, Byung-Hyun Daniel;Cho, Hee-Min;Cho, Kuk Young
    • Journal of the Korean Electrochemical Society
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    • v.17 no.1
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    • pp.7-12
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    • 2014
  • There is increasing demand on the reducing the weight and the volume of the major components in lithium secondary battery to improve energy density. Separator not only provides pathway for lithium ion movement but also prevents direct contact between anode and cathode. Herein we fabricated polyethylene separator by varying biaxial stretching ratio to obtain membrane thickness of 16, 12, and $9{\mu}m$. Mechanical and thermal properties of the separator with different thickness were investigated. Also rate capability and charge-discharge cycle property up to 500 cycles were studied using coin type full-cell with $LiCoO_2$ and graphite as a cathode and an anode, respectively. All the cells using separator with different thickness demonstrated excellent capacity retention after 500cycles (around 80%). Considering the rate capability, cell using separator with thickness of $9{\mu}m$ showed best performance. Interestingly, separator thickness of $9{\mu}m$ was more resistant to heat contraction compared to that of $16{\mu}m$ separator.

Calcium Channel Blockers Suppress the Responses of Rat Dorsal Horn Cell to Nociceptive Input (쥐 척수후각세포의 유해자극 반응에 대한 칼슘이온통로 차단제의 억제작용)

  • Kang, Sok-Han;Kim, Kee-Soon;Shin, Hong-Kee
    • The Korean Journal of Physiology and Pharmacology
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    • v.1 no.6
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    • pp.625-637
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    • 1997
  • Calcium ions are implicated in a variety of physiological functions, including enzyme activity, membrane excitability, neurotransmitter release, and synaptic transmission, etc. Calcium antagonists have been known to be effective for the treatment of exertional angina and essential hypertension. Selective and nonselective voltage-dependent calcium channel blockers also have inhibitory action on the acute and tonic pain behaviors resulting from thermal stimulation, subcutaneous formalin injection and nerve injury. This study was undertaken to investigate the effects of iontophoretically applied $Ca^{++}$ and its antagonists on the responses of WDR (wide dynamic range) cells to sensory inputs. The responses of WDR cells to graded electrical stimulation of the afferent nerve and also to thermal stimulation of the receptive field were recorded before and after iontophoretical application of $Ca^{++}$, EGTA, $Mn^{++}$, verapamil, ${\omega}-conotoxin$ GVIA, ${\omega}-conotoxin$ MVIIC and ${\omega}-agatoxin$ IVA. Also studied were the effects of a few calcium antagonists on the C-fiber responses of WDR cells sensitized by subcutaneous injection of mustard oil (10%). Calcium ions and calcium channel antagonists ($Mn^{++}$, verapamil, ${\omega}-conotoxin$ GVIA & ${\omega}-agatoxin$ IVA) current-dependently suppressed the C-fiber responses of WDR cells without any significant effects on the A-fiber responses. But ${\omega}-conotoxin$ MVIIC did not have any inhibitory actions on the responses of WDR cell to A-fiber, C-fiber and thermal stimulation. Iontophoretically applied EGTA augmented the WDR cell responses to C-fiber and thermal stimulations while spinal application of EGTA for about $20{\sim}30\;min$ strongly inhibited the C-fiber responses. The augmenting and the inhibitory actions of EGTA were blocked by calcium ions. The WDR cell responses to thermal stimulation of the receptive field were reduced by iontophoretical application of $Ca^{++}$, verapamil, ${\omega}-agatoxin$ IVA, and ${\omega}-conotoxin$ GVIA but not by ${\omega}-conotoxin$ MVIIC. The responses of WDR cells to C-fiber stimulation were augmented after subcutaneous injection of mustard oil (10%, 0.15 ml) into the receptive field and these sensitized C-fiber responses were strongly suppressed by iontophoretically applied $Ca^{++}$, verapamil, ${\omega}-conotoxin$ GVIA and ${\omega}-agatoxin$ IVA. These experimental findings suggest that in the rat spinal cord, L-, N-, and P-type, but not Q-type, voltage-sensitive calcium channels are implicated in the calcium antagonist-induced inhibition of the normal and the sensitized responses of WDR cells to C-fiber and thermal stimulation, and that the suppressive effect of calcium and augmenting action of EGTA on WDR cell responses are due to changes in excitability of the cell.

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Effects of Glucose and IGF-I on Expression of Glucose Transporter 1 (Glut1) and Development of Preimplantation Mouse Embryo (생쥐의 착상전 배아의 발생과 Glucose Transporter 1 (Glut1) 발현에 대한 포도당과 IGF-I의 영향)

  • 전한식;계명찬;김종월;강춘빈;김문규
    • Development and Reproduction
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    • v.2 no.2
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    • pp.205-212
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    • 1998
  • A sodium-independent facilitative glucose transporter 1 (Glut1) is a major route by which glucose can be transported across the plasma membrane of mouse embryo. Although it has been known that insulin-like growth factor-I (IGF-I) promotes glucose transport into the mouse embryo, whether IGF-I directly regulates transcription of Glut1 has been uncovered in mouse preimplantation embryo. This study was aimed to elucidate the role of glucose and IGF-I in development and Glut1 expression in preimplantation mouse embryo. Two-cell embryos developed in blastocyst regardless of the glucose in the presence of pyruvate. IGF-I significantly increased the number of blastomeres in the mid-blastula. Deprivation of glucose did not affect the amount of Glut1 transcripts in morula cultured from 2-cell embryo. IGF-I potentiated Glut1 expression in morula cultured from 2-cell embryo even in the absence of glucose. Taken together, it is concluded that depletion of glucose does not promote Glut1 expression the in morula cultured form 2-cell embryo, and that increment of Glut1 expression possibly mediates embryotropic effect of IGF-I on preimplantation mouse embryo.

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생쥐 초기 배아에서 Aquaporin 8과 9의 발현에 관한 연구

  • 신현상;계명찬;강수만;이성은;이지원;강한승;김문규
    • Proceedings of the Korean Society of Developmental Biology Conference
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    • 2003.10a
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    • pp.68-68
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    • 2003
  • Aquaporin은 막관통 통로 단백질(transmembrane channel protein)로서, 삼투압의 농도구배에 따라 세포막을 가로질러 물분자를 이동시키는 기능을 하고 있다. 포유류 초기배아에서 포배강 형성은 영양외배엽세포에서 $Na^+ / K^+$ATPase에 의한 이온 농도 구배가 형성되면 auqaporin에 의해 물이 포배강으로 유입되면서 이루어진다. 본 연구에서는 생쥐 초기배아에서 반정량적인 역전사 중합효소 연쇄반응 방법(semi-quantitative RT-PCR)과 실시간 역전사 중합효소 연쇄반응 방법(real-time RT-PCR)을 통하여 AQP8과 9의 mRNA발현을 조사하고 다중 면역형광현미경 방법(confocal immunofluorescence microscopy)을 통해 단백질 발현양상을 분석하였다. AQP8 mRNA는 상실기까지 발현되지 않다가 포배기에 이르러 발현되었고 AQP9 mRNA는 수정란에서부터 발현되어 포배기에는 유의할 정도로 증가하였다. 따라서 AQP8 mRNA는 배아유전자가 활성화되어 나타나는 것이고 AQP9 mRNA는 모계유전자 기원임을 알 수 있었다. AQP8 단백질은 상실배 단계까지 발현되지 않다가 포배시기에 영양외배엽세포사이의 접합면에 발현되었고 AQP9 단백질은 상실배 시기에 할구 사이의 인접 부위에서 강하게 발현되었다가 포배시기에는 세포간의 접합면에 약하게 발현하는 경향을 나타내었다. 실시간 역전사 중합효소 연쇄반응 방법으로 조사한 결과 포배에서 물과 글리세롤을 통과시키는 AQP9는 mRNA의 발현양이 AQP8보다 약 4배 정도 많았다. 또한 포배기에 이르러서야 물만을 통과시키는 AQP8의 발현이 나타나는 것을 보아 포배강 형성시 외부에서 영양외배엽을 통해 포배강으로 유입되는 물의 이동(trans- trophectodermal water movements)에 AQP9보다 AQP8이 더 중요하게 관여할 것으로 사료된다., K, Pb, Cd, Cr, Co, Cu, Ni)을 측정하였다. 실험 조건1의 결과로서 각 국의 유아용 일회용 기저귀의 중금속 함량은 거의 유사한 경향을 나타내었으며 Cr, Zn, Pb, Ni, Mn, Mg, Li, K는 detection limit(2 ppm) 이하였고, Cd, Fe, Co, Cu, Ca, Al, Sr는 검출되었지만 기준치 이하였다. 실험 조건2의 결과로서 측정 항목(Cr, Sb, Cd, Pb, Ni, Co, Cu)중 Cr, Cd, Ni, Cu는 detection limit(0.1 ppm) 이하였고, Sb, Pb, Co는 검출되었지만 기준치 이하였다.았다. 4%의 경우에는 8$0^{\circ}C$이하로 온도를 낮추는 것이 좋은 상태를 나타내었다. 이와 같은 결과는 일반적으로 화학적 레팅을 4%, 7%에서한 선행결과와 상당히 다른 결과이다.염 농도가 증가할수록 감소 현상을 보였다.X>, 75BG30은 8.6$\mu\textrm{m}$, 75BG40은 7.02$\mu\textrm{m}$로 나타났다. 따라서 경화제 양에 관계없이 10$\mu\textrm{m}$ 이하로 나타나, 경화제 10$m\ell$만으로 미세한 크기를 얻을 수 있음을 알 수 있다. 젤리 강도 변화에 따른 차이는 300BF는 78.09$\mu\textrm{m}$ 300BG는 56.32$\mu\textrm{m}$로, 75BF나 75BG에 비하여 현저히 증가하여, 젤라틴의 젤리 강도는 캡슐 제조 조건의 주요한 변수임을 알 수 있다.추출물 투여시 혈당강하 및 혈중콜레스테롤 강하가 나타났으며, 상엽복합추출물 투여와 운동을 병행시 이러한 감소 효과가 더 뚜렷하게 나타났다.교육의 적임자로 보는 시각이 비교적 높았고 약 1/2정도는 영양교육에 참여하겠다는 의지를 가지고 있을 뿐만 아니라 실제로 영양지도를

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The Acid Rock Drainage and Hydraulic Characteristics of the Waste Rock Dump (폐석적치장의 산성배수발생 및 수리특성 분석)

  • Cheong, Young Wook;Ji, Sang Woo;Yim, Gil Jae
    • Journal of the Korean GEO-environmental Society
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    • v.5 no.4
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    • pp.13-24
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    • 2004
  • This study was carried out to plan the prevention of the generation and discharge of Acid Rock Drainage (ARD). The Acid Base Accounting(ABA) test was performed for geological materials such as pit wall, waste rock and stream sediments near the Imgi abandoned pyrophyllite mine in Busan, Korea. In addition, hydraulic characteristics were tested with the disk tension infiltrometer around the waste rock dump. Maximum Potential Acidity(MPA) of geological materials near the Imgi mine was 246.942kg $H_2SO_4/t$, and maximum Acid Neutralising Capacity(ANC) was 8.7kg $H_2SO_4/t$. These results indicate the pit wall and waste rock, except most of stream sediments are acid generating geological materials. These have salt and free hydrogen ion which resulted from oxidation of sulfides. Hence they could be convert rain water to acid rock drainage. Although the waste rock dump of the Imgi mine have very low infiltration rate, slopes of the waste rock dump have many "V" type erosion gullies and multi-layers. These gullies and multi-layers have coarse clastic particle layers which have very large hydraulic conductivity. Through this coarse clastic particle layer a large part of rain flow into ground. And also this layer could function as aeration path which induced oxidation of sulfide minerals and generation of ARD continuously.

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Effects of Olanzapine on the Pacemaker Potentials of Interstitial Cells of Cajal in Murine Small Intestine (생쥐 소장 카할세포에서 발생하는 향도잡이 기능의 올란자핀 효능에 관한 연구)

  • Kim, Byung Joo
    • Journal of Life Science
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    • v.29 no.9
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    • pp.1010-1015
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    • 2019
  • The interstitial cells of Cajal (ICCs) are the pacemaker cells in the gastrointestinal (GI) tract. In the present study, the effects of olanzapine, an atypical antipsychotic agent, on pacemaker potentials in cultured ICCs from the small intestine of the mouse were investigated. The whole-cell patch-clamp configuration was used to record pacemaker potentials from cultured ICCs. Olanzapine produced pacemaker depolarizations in a concentration-dependent manner in current clamp mode. Methoctramine, a muscarinic $M_2$ receptor antagonist, did not inhibit olanzapine-induced pacemaker depolarizations, whereas 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP) muscarinic $M_3$ receptor antagonist did inhibit it. When guanosine 5'-[${\beta}$-thio] diphosphate (GDP-${\beta}$-S; 1 mM) was in the pipette solution, olanzapine-induced pacemaker depolarization was blocked. Also, low $Na^+$ solution externally eliminated the generation of pacemaker potentials and inhibited the olanzapine-induced pacemaker depolarizations. Additionally, the nonselective cation channel blocker, flufenamic acid, inhibited the olanzapine-induced pacemaker depolarizations. Pretreatment with U-73122, an active phospholipase C (PLC) inhibitor, also eliminated the generation of pacemaker potentials and suppressed the olanzapine-induced pacemaker depolarizations. These results suggested that olanzapine modulates the pacemaker potentials through muscarinic $M_3$ receptor activation by G protein-dependent external $Na^+$ and PLC pathway in the ICCs. Therefore, olanzapine could affect intestinal motility through ICCs.

Role of $Ca^{2+}$ for Inactivation of N-type Calcium Current in Rat Sympathetic Neurons (흰쥐 교감신경 뉴론 N형 칼슘전류의 비활성화에 미치는 칼슘효과)

  • Goo, Yong-Sook;Keith S. Elmslie
    • Progress in Medical Physics
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    • v.14 no.1
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    • pp.54-67
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    • 2003
  • The voltage-dependence of N-type calcium current inactivation is U-shaped with the degree of inactivation roughly mirroring inward current. This voltage-dependence has been reported to result from a purely voltage-dependent mechanism. However, $Ca^{2+}$-dependent inactivation of N-channels has also been reported. We have investigated the role of $Ca^{2+}$ in N-channel inactivation by comparing the effects of $Ba^{2+}$and $Ca^{2+}$ on whole-cell N-current in rat superior cervical ganglion neurons. For individual cells in-activation was always larger in $Ca^{2+}$ than in $Ba^{2+}$ even when internal EGTA (11 mM) was replaced with BAPTA (20 mM). The inactivation vs. voltage relationship was U-shaped in both divalent cations. The enhancement of inactivation by $Ca^{2+}$ was inversely related with the magnitude of inactivation in $Ba^{2+}$ as if the mechanisms of inactivation were the same in both $Ba^{2+}$ and $Ca^{2+}$. In support of this idea we could separate fast ( ${\gamma}$ ~150 ms) and slow ( ${\gamma}$ ~ 2500 ms) components of inactivation in both $Ba^{2+}$and $Ca^{2+}$ using 5 sec voltage steps. Differential effects were observed on each component with $Ca^{2+}$ enhancing the magnitude of the fast component and the speed of the slow component. The larger amplitude of fast component indicates that the more channels inactivate via this pathway with $Ca^{2+}$ than with $Ba^{2+}$, but the stable time constants support the idea the fast inactivation mechanism is identical in $Ba^{2+}$and $Ca^{2+}$. The results do not support a $Ca^{2+}$-dependent mechanism for fast inactivation. However, the $Ca^{2+}$-induced acceleration of the slowly inactivating component could result from a $Ca^{2+}$-dependent process.

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