• Title/Summary/Keyword: $K_{2p}$ channels

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The Effects of Acupuncture at the GV20 and GV22 on the Electroencephalogram(EEG) (백회(百會)(GV20).신회(顖會)(GV22) 자침이 뇌파에 미치는 영향)

  • Lee, Sang-Hun;Ryu, Yeon-Hee;Kwon, O-Sang;Sohn, In-Chul
    • Korean Journal of Acupuncture
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    • v.29 no.3
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    • pp.467-475
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    • 2012
  • Objectives : The aim of this study was to examine the effects of Acupuncture at the GV20 and GV22 on normal human beings using power spectrum analysis. Methods : Electroencephalogram(EEG) power spectrum exhibits site-specific and state-related differences in various frequency bands. 8 channels Background Electroencephalogram (EEG) was carried out in 30 subjects(24 females and 4 males). Results : In ${\delta}$(theta) band, the power values decreased significantly at the 8-channel average value(p=0.03) and especially at T3(p=0.02), T4(p=0.001) and P3(p=0.03). In ${\alpha}$(alpha) band, the power values have no significant changes. In ${\beta}$(beta)band, the power values increased significantly at the 8-channel average value (p=0.02) and especially at T4(p=0.003), P3 (p= 0.03) and P4(0.02). In ${\beta}/{\delta}$(beta/theta) ratio, the value increased significantly at the 8-channel average value(p=0.002) and especially at Fp2(p=0.05), F4(p=0.007), T3(0.012), T4(0.005), P3 (0.007) and P4(0.03) Conclusions : Through this data, we conclude that acupuncture at the GV20 and GV22 on normal human beings could have possibility to awake the cerebral cortex by the functional mechanism.

Characterization of an Ion Channel Prepared from Tomato Roots and Inhibitory Effects by Heavy Metal Ions (토마토 뿌리조직에서 분리한 이온채널의 중금속에 의한 저해)

  • Shin, Dae-Seop;Han, Min-Woo;Kim, Young-Kee
    • Applied Biological Chemistry
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    • v.47 no.4
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    • pp.390-395
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    • 2004
  • In order to characterize ion channels present in tomato roots, microsomes were incorporated into an artificial lipid bilayer arranged for electrophysiological analysis. Of the five different ion channels that could be found, a channel of 450 pS conductance was found most frequently. This channel displayed subconductance states of 450, 257 and 105 pS. All subconductance states showed linear current-voltage relationships. At positive holding potentials, high frequency of transient channel openings was observed; however, at negative potentials, the open times were long and open probability high. Po was 0.83 at -40 mV. When an additional 50 mM $K^+\;or\;Na^+$ was added to the cis side of bilayer, the reversal potentials shifted in the negative direction to near -10 mV. Thus, the 450 pS cation channel selects poorly between $K^+\;and\;Na^+$. In the presence of $100\;{\mu}M$ metal ions, the channel activity was severely inhibited by $La^{3+},\;Ba^{2+},\;and\;Zn^{2+}$, and Po was decreased to 0.2 or even less. However, $Al^{3+}\;and\;Cd^{2+}$ decreased the activity by only 20%. Interestingly, each metal ion showed different kinetics of channel inhibition. While $500\;{\mu}M\;La^{3+}$ inhibited the activities of all subconductance state, 1 mM $Zn^{2+}$ inhibited all except the 105 pS state. $Cd^{2+}$ changed the gating of the channel from a long-opening state to brief transient openings even at negative holding potentials. These data represent that the metal ions may have different binding sites on the channel protein and could be useful modulators and probes to investigate structural characteristics as well as the functional roles of the 450 pS channel on the root physiology.

Gate-Controlled Spin-Orbit Interaction Parameter in a GaSb Two-Dimensional Hole gas Structure

  • Park, Youn Ho;Koo, Hyun Cheol;Shin, Sang-Hoon;Song, Jin Dong;Kim, Hyung-Jun;Chang, Joonyeon;Han, Suk Hee;Choi, Heon-Jin
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.382-383
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    • 2013
  • Gate-controlled spin-orbit interaction parameter is a key factor for developing spin-Field Effect Transistor (Spin-FET) in a quantum well structure because the strength of the spin-orbit interaction parameter decides the spin precession angle [1]. Many researches show the control of spin-orbit interaction parameter in n-type quantum channels, however, for the complementary logic device p-type quantum channel should be also necessary. We have calculated the spin-orbit interaction parameter and the effective mass using the Shubnikov-de Haas (SdH) oscillation measurement in a GaSb two-dimensional hole gas (2DHG) structure as shown in Fig 1. The inset illustrates the device geometry. The spin-orbit interaction parameter of $1.71{\times}10^{11}$ eVm and effective mass of 0.98 $m^0$ are obtained at T=1.8 K, respectively. Fig. 2 shows the gate dependence of the spin-orbit interaction parameter and the hole concentration at 1.8 K, which indicates the spin-orbit interaction parameter increases with the carrier concentration in p-type channel. On the order hand, opposite gate dependence was found in n-type channel [1,2]. Therefore, the combined device of p- and n-type channel spin transistor would be a good candidate for the complimentary logic device.

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Factors Influencing on Health Promoting Behavior of Community-dwelling Older Adults (지역사회 거주 노인의 건강증진행위에 영향을 미치는 요인)

  • Jang, Ji-Hye;Shin, Yong Soon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.2
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    • pp.460-469
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    • 2020
  • The purpose of this study was to examine the predictive factors for health promotion behaviors of older adults in rural areas. A theoretical substruction was constructed to test hypothetical models based on Pender's health promotion model. The data was collected from 199 older adults aged 65 years or older, who resided in G city, by using a structured questionnaire. The questionnaires contained items on individual characteristics, health literacy, self efficacy and health promoting behavior. The data was analyzed with a t-test, ANOVA, Pearson's correlation coefficients and hierarchical multiple regression analysis using SPSS 20.0 for Windows. The predictive factors for the health promotion behavior were the number of health information channels (β=.16, p=.031) and self efficacy (β=.53, p<.001). The total explanatory power of these factors was 30.8%. A nursing intervention plan for improving health promoting behaviors of older adults should be developed and applied, with a focus on self-efficacy and health information channels. Further longitudinal studies are needed to help confirm relevant measurement of the level of health promoting behaviors of older adults.

Actin Filaments Regulate the Stretch Sensitivity of Large Conductance $Ca^{2+}$-Activated $K^+$ Channel in Rabbit Coronary Arterial Smooth Muscle Cells

  • Lin Piao;Earm, Yung-E;Wonkyung Ho
    • Proceedings of the Korean Biophysical Society Conference
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    • 2002.06b
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    • pp.35-35
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    • 2002
  • The large conductance $Ca^{2+}$ -activated $K^{+}$ channels ($BK_{Ca}$) in vascular smooth muscle have been considered to function as a negative feedback in pressure-induced vasoconstriction. In the present study, the function of cytoskeletons in the regulation of $BK_{Ca}$ and its stretch sensitivity was investigated. Using the inside-out patch clamp technique, we recorded single channel activities of $BK_{Ca}$ with 150 mM KCl in the bath solution (pCa=6.5).(omitted)itted)

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Possible Involvement of $Ca^{2+}$ Activated $K^+$ Channels, SK Channel, in the Quercetin-Induced Vasodilatation

  • Nishida, Seiichiro;Satoh, Hiroyasu
    • The Korean Journal of Physiology and Pharmacology
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    • v.13 no.5
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    • pp.361-365
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    • 2009
  • Effects of quercetin, a kind of flavonoids, on the vasodilating actions were investigated. Among the mechanisms for quercetin-induced vasodilatation in rat aorta, the involvement with the $Ca^{2+}$ activated $K^+$ ($K_{Ca}$) channel was examined. Pretreatment with NE ($5\;{\mu}M$) or KCl (60 mM) was carried out and then, the modulation by quercetin of the constriction was examined using rat aorta ring strips (3 mm) at $36.5^{\circ}C$. Quercetin (0.1 to $100\;{\mu}M$) relaxed the NE-induced vasoconstrictions in a concentrationdependent manner. NO synthesis (NOS) inhibitor, NG-monomethyl-L-arginine acetate (L-NMMA), at $100\;{\mu}M$ reduced the quercetin ($100\;{\mu}M$)-induced vasodilatation from $97.8{\pm}3.7%$ (n=10) to $78.0{\pm}11.6%$ (n=5, p<0.05). Another NOS inhibitor, L-NG-nitro arginine methyl ester (L-NAME), at $10\;{\mu}M$ also had the similar effect. In the presence of both $100\;{\mu}M$ L-NMMA and $10\;{\mu}M$ indomethacin, the quercetin-induced vasodilatation was further attenuated by $100\;{\mu}M$ tetraethylammonium (TEA, a $K_{Ca}$ channel inhibitor). Also TEA decreased the quercetin-induced vasodilatation in endothelium-denuded rat aorta. Used other $K_{Ca}$ channel inhibitors, the quercetin-induced vasodilatation was attenuated by $0.3\;{\mu}M$ apamin (a SK channel inhibitor), but not by 30 nM charybdotoxin (a BK and IK channel inhibitor). Quercetin caused a concentration-dependent vasodilatation, due to the endotheliumdependent and -independent actions. Also quercetin contributes to the vasodilatation selectively with SK channel on smooth muscle.

Preemptive application of QX-314 attenuates trigeminal neuropathic mechanical allodynia in rats

  • Yoon, Jeong-Ho;Son, Jo-Young;Kim, Min-Ji;Kang, Song-Hee;Ju, Jin-Sook;Bae, Yong-Chul;Ahn, Dong-Kuk
    • The Korean Journal of Physiology and Pharmacology
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    • v.22 no.3
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    • pp.331-341
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    • 2018
  • The aim of the present study was to examine the effects of preemptive analgesia on the development of trigeminal neuropathic pain. For this purpose, mechanical allodynia was evaluated in male Sprague-Dawley rats using chronic constriction injury of the infraorbital nerve (CCI-ION) and perineural application of 2% QX-314 to the infraorbital nerve. CCI-ION produced severe mechanical allodynia, which was maintained until postoperative day (POD) 30. An immediate single application of 2% QX-314 to the infraorbital nerve following CCI-ION significantly reduced neuropathic mechanical allodynia. Immediate double application of QX-314 produced a greater attenuation of mechanical allodynia than a single application of QX-314. Immediate double application of 2% QX-314 reduced the CCI-ION-induced upregulation of GFAP and p-p38 expression in the trigeminal ganglion. The upregulated p-p38 expression was co-localized with NeuN, a neuronal cell marker. We also investigated the role of voltage-gated sodium channels (Navs) in the antinociception produced by preemptive application of QX-314 through analysis of the changes in Nav expression in the trigeminal ganglion following CCI-ION. Preemptive application of QX-314 significantly reduced the upregulation of Nav1.3, 1.7, and 1.9 produced by CCI-ION. These results suggest that long-lasting blockade of the transmission of pain signaling inhibits the development of neuropathic pain through the regulation of Nav isoform expression in the trigeminal ganglion. Importantly, these results provide a potential preemptive therapeutic strategy for the treatment of neuropathic pain after nerve injury.

Polyamine Induces Apoptosis Through the Calcium Signaling in Human Prostate Cancer Cells (전립선암세포에 있어서 폴리아민에 의한 칼슘신호와 세포사멸)

  • Song Hwi-June;Kim Ji-Young;Yoo Mi-Ae;Chung Hae-Young;Kim Jong-Min;Kim Byeong-Gee
    • Journal of Life Science
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    • v.16 no.3 s.76
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    • pp.433-441
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    • 2006
  • Polyamines are essential for the normal cell growth and differentiation. They are also known to have paradoxical dual effects on cell proliferation. In this paper we show that the excess amount of polyamines induces apoptosis through the modulation of calcium signaling in LNCaP human prostate cancer cells. Polyamines, particularly spermidine and spermine, stimulated cell proliferation at a lower concentration (under 10 ${\mu}M$), but it inhibited cell viability at a higher concentration (40 ${\mu}M$). The levels of intracellular $Ca^{2+}$ concentration were increased only at a high concentration of polyamines treatment without any noticeable changes at lower concentrations. Nifedipine did not alter the increase of polyamine-induced $Ca^{2+}$ levels, but flufenamic acid totally abolished the increase of intracellular $Ca^{2+}$ levels. These results mean that polyamines induce $Ca^{2+}$ influx from the surroundings through nonselective cation channels on the cell membrane. The expression of Bcl-2 protein was almost completely blocked, but the level of Bax protein was increased dramatically in the cells treated with high concentration of polyamine. The present study shows that polyamines at a high concentration induce apoptosis through the modulation of intracellular calcium signaling. The increase of intracellular calcium level induced by polyamines, was possibly a result from the extracellular calcium influx through the nonselective cation channels.

Decreased Voltage Dependent $K^+$ Currents in Cerebral Arterial Smooth Muscle Cells of One-Kidney, One-Clip Goldblatt Hypertensive Rat

  • Oh, Young-Sun;Kim, Se-Hoon;Kim, Hoe-Suk;Jeon, Byeong-Hwa;Chang, Seok-Jong;Kim, Kwang-Jin
    • The Korean Journal of Physiology and Pharmacology
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    • v.3 no.5
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    • pp.471-479
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    • 1999
  • The Kv channel activity in vascular smooth muscle cell plays an important role in the regulation of membrane potential and blood vessel tone. It was postulated that increased blood vessel tone in hypertension was associated with alteration of Kv channel and membrane potential. Therefore, using whole cell mode of patch-clamp technique, the membrane potential and the 4-AP-sensitive Kv current in cerebral arterial smooth muscle cells were compared between normotensive rat and one-kidney, one-clip Goldblatt hypertensive rat (lK,lC-GBH rat). Cell capacitance of hypertensive rat was similar to that of normotensive rat. Cell capacitance of normotensive rat and 1K,lC-GBH rat were $20.8{\pm}2.3$ and $19.5{\pm}1.4$ pF, respectively. The resting membrane potentials measured in current clamp mode from normotensive rat and 1K,lC-GBH rat were $-45.9{\pm}1.7$ and $-38.5{\pm}1.6$ mV, respectively. 4-AP (5 mM) caused the resting membrane potential hypopolarize but charybdotoxin $(0.1\;{\mu}M)$ did not cause any change of membrane potential. Component of 4-AP-sensitive Kv current was smaller in 1K,lC-GBH rat than in normotensive rat. The voltage dependence of steady-state activation and inactivation of Kv channel determined by using double-pulse protocol showed no significant difference. These results suggest that 4-AP-sensitive Kv channels playa major role in the regulation of membrane potential in cerebral arterial smooth muscle cells and alterations of 4-AP-sensitive Kv channels would contribute to hypopolarization of membrane potential in 1K,lC-GBH rat.

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[ $Ce^{4+}$ ]-Stimulated Ion Fluxes Are Responsible for Apoptosis and Taxol Biosynthesis in Suspension Cultures of Taxus Cells

  • Li Jing-Chuan;Ge Zhi-Qiang;Yuan Ying-Jin
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.2
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    • pp.109-114
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    • 2005
  • Ion fluxes across the plasma membrane activated by 1 mM $Ce^{4+}$, cell apoptosis and taxol biosynthesis in suspension cultures of Taxus cusp/data were studied. The extracellular pH sharply decreased upon the addition of 1 mM $Ce^{4+}$, then increased gradually and exceeded the initial pH value over a time period of 12 h. The extracellular $Ca^{2+}$ concentration decreased within the first 3 h after the addition of $Ce^{4+}$, then gradually decreased to one third of initial value in control at about 72 h and remained unchanged afterwards. Experiments with an ion channel blocker and a $Ca^{2+}$-channel blocker indicated that the dynamic changes in extracellular pH and the $Ca^{2+}$ concentration resulted from the $Ce^{4+}$-induced activation of W uptake and $Ca^{2+}$ influx across the plasma membrane via ion channels. A pretreatment of the ion channel blocker initiated $Ce^{4+}$-treated cells to undergo necrosis, and the prior addition of the $Ca^{2+}$-channel blocker inhibited $Ce^{4+}$-induced taxol biosynthesis and apoptosis. It is thus inferred that W uptake is necessary for cells to survive a $Ce^{4+}$-caused acidic environment and is one of the mechanisms of $Ce^{4+}$-induced apoptosis. Furthermore, the $Ca^{2+}$ influx across the plasma membrane mediated both the $Ce^{4+}$-induced apoptosis and taxol biosynthesis.