• Title/Summary/Keyword: capacitance currents type

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Altered Calcium Current of the Vascular Smooth Muscle in Renal Hypertension

  • Nam, Sang-Chae;Jeong, Hye-Jeon;Kim, Won-Jae;Lee, Jong-Un
    • The Korean Journal of Physiology and Pharmacology
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    • v.3 no.3
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    • pp.351-356
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    • 1999
  • The present study was aimed at investigating whether the calcium current in the vascular smooth muscle (VSM) cells is altered in renal hypertension. Two-kidney, one clip (2K1C) and deoxycorticosterone acetate (DOCA)-salt hypertension were made in Sprague-Dawley rats. Rats without clipping the renal artery or implanting DOCA were used as control for 2K1C and DOCA-salt hypertension, respectively. Four weeks after clipping, systolic blood pressure was significantly higher in 2K1C rats than in control $(192{\pm}24\;and\;119{\pm}4$ mmHg, respectively, n=16 each). DOCA-salt rats also showed a higher blood pressure $(180{\pm}15$ mmHg, n=18) compared with control $(121{\pm}6$ mmHg, n=14). VSM cells were enzymatically and mechanically isolated from basilar arteries. Single relaxed VSM cells measured $5{\sim}10\;{\mu}m$ in width and $70{\sim}150\;{\mu}m$ in length were obtained. VSM cells could not be differentiated in size and shape between hypertensive and normotensive rats under light microscopy. High-threshold (L-type) calcium currents were recorded using whole-cell patch clamp technique. The amplitude of the current recorded from VSM cells was larger in 2K1C hypertension than in control. Neither the voltage-dependence of the calcium current nor the cell capacitance was significantly affected by 2K1C hypertension. By contrast, the amplitude of the calcium current was not altered in DOCA-salt hypertension. These results suggest that high-threshold calcium current of the VSM cells is altered in 2K1C hypertension, and that calcium channel may not be involved in calcium recruitment of VSM in DOCA-salt hypertension.

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A Study on the Characteristics Analysis and Design of High Sensitivity Silicon Photodiode for Laser Detector (레이저 검출용 고감도 실리콘 포토다이오드 제조 및 특성 분석에 관한 연구)

  • Lee, Jun-Myung;Kang, Eun-Young;Park, Keon-Jun;Kim, Yong-Kab
    • The Journal of the Korea institute of electronic communication sciences
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    • v.9 no.5
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    • pp.555-560
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    • 2014
  • In order to improve spectrum sensitivity of photodiode for detection of the laser wavelength at 850 nm ~ 1000 nm of near-infrared band, this study has produced silicon-based photodiode whose area is $5000{\mu}m{\times}2000{\mu}m$, and the thickness is $280{\mu}m$. It was packed by the TO-5 type. The electrical properties of the dark currents have valued of approximately 0.1 nA for 5 V reverse bias, while the capacitance showed 32.5 pF at frequency range of 1 kHz and about 32.4 pF at the range of 200 kHz for 0 V. In addition, the rising time of output signal was as fast response as 20.92 ns for 10V. For the optical properties, the best spectrum sensitivity was 0.57 A/W for 890 nm, while it was relatively excellent value of 0.37 A/W for 1,000 nm. Over all, there were good spectrum sensitivity for this diode over the range of 870 ~ 920 nm.

Identification of ATP-sensitive $K^+$ Conductances in Male Rat Major Pelvic Ganglion Neurons

  • Park, Kyu-Sang;Cha, Seung-Kyu;Lee, Keon-Il;Jun, Jae-Yeoul;Jeong, Seong-Woo;Kong, In-Deok;Lee, Joong-Woo
    • The Korean Journal of Physiology and Pharmacology
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    • v.6 no.5
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    • pp.247-253
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    • 2002
  • Major pelvic ganglia (MPG) neurons are classified into sympathetic and parasympathetic neurons according to the electrophysiological properties; membrane capacitance (Cm), expression of T-type $Ca^{2+}$ channels, and the firing patterns during depolarization. In the present study, function and molecular expression of ATP-sensitive $K^+\;(K_{ATP})$ channels was investigated in MPG neurons of male rats. Only in parasympathetic MPG neurons showing phasic firing patterns, hyperpolarizing changes were elicited by the application of diazoxide, an activator of $K_{ATP}$ channels. Glibenclamide $(10{\mu}M),$ a $K_{ATP}$ channel blocker, completely abolished the diazoxide-induced hyperpolarization. Diazoxide increased inward currents at high $K^+$ (90 mM) external solution, which was also blocked by glibenclamide. The metabolic inhibition by the treatment with mitochondrial respiratory chain inhibitors (rotenone and antimycin) hyperpolarized the resting membrane potential of parasympathetic neurons, which was not observed in sympathetic neurons. The hyperpolarizing response to metabolic inhibition was partially blocked by glibenclamide. RT-PCR analysis revealed that MPG neurons mainly expressed the $K_{ATP}$ channel subunits of Kir6.2 and SUR1. Our results suggest that MPG neurons have $K_{ATP}$ channels, mainly formed by Kir6.2 and SUR1, with phenotype-specificity, and that the conductance through this channel in parasympathetic neurons may contribute to the changes in excitability during hypoxia and/or metabolic inhibition.

A Study on the changes of electric change induced by Tanchim (彈鍼) manipulation during acupuncture therapy (자침시(刺鍼時) 탄침(彈鍼)의 수기자극(手技刺戟)이 전위변화(電位變化)에 미치는 영향(影響))

  • Kim, Yong-Deug;Kim, Young-Tae;Park, Sung-Sub;Park, Gwi-Jong;Sohn, In-Cheul;Kim, Kyung-Sik
    • Korean Journal of Acupuncture
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    • v.21 no.4
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    • pp.1-19
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    • 2004
  • Objectives : To understanding biological mechanism of acupuncture therapy, we have proposed a hypothesis. First of all, there exists electric property in meridian and meridian point. Second of all, energy flowing in meridian is related with electric property. Third of all, there is electronic interaction between the operator who performs acupuncture therapy and the receiver who is given acupuncture therapy. Forth of all, acupuncture effects may depend on the electric capacity which is transferred between the operator and the receiver via acupuncture needle. Methods : Under the hypothesis, we studied the effects of electric change in $ST_{37}(+)\;and\;ST_{39}(-)$ generated by Tanchim (彈鍼) manipulation which was stimulated at $ST_{36}$ point. And compared with data on the changes of electric change from the hand of the operator during acupuncture stimulation. Electric charge induced via acupuncture needle from the operator may be important factor that causes the changes of electric change in meridian and acupoint in the receiver. Therefore we investigated the changes of electric charge induced by the operator using Maclab 400 by the following methods. The one was in stable electric circle condition and the other was in unstable electric circle condition. Results : In this experiments, the changes of electric change from the stimulation type of Tanchim manipulation performed in our lab condition in acupuncture therapy was induced at least three factor, one was the difference of bio-potentials between the operator and the receiver of acupuncture therapy, another was the depth of acupuncture insertion from the skin of the receiver, the other was an electromyogram of the receiver. Conclusion : The data imply that the first factor should make a capacitance current when the operator touched the acupuncture needle which was inserted in the receiver. Therefore, the results suggest that capacitance currents stimulus in electronic view may be important factor in acupuncture therapy between the operator and the receiver of acupuncture therapy.

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A Study on the changes of electric charge induced by Apchim (押鍼) manipulation during acupuncture therapy (자침시(刺鍼時) 압침(押鍼)의 수기자극(手技刺戟)이 전위변화(電位變化)에 미치는 영향(影響))

  • Song, Moon-Young;Shim, Won-Bo;Kim, Young-Tae;Baek, Dae-Bong;Ahn, Sung-Hun;Kim, Kyoung-Sik;Sohn, In-Cheul
    • Korean Journal of Acupuncture
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    • v.22 no.4
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    • pp.9-27
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    • 2005
  • Objective : hypothesis. First of all, there exists electric property in meridian and meridian point. Second of all, energy flowing in meridian is related with electric property. Third of all, there is electronic interaction between the operator who performs acupuncture therapy and the receiver who is given acupuncture therapy. Forth of all, acupuncture effects may depend on the electric capacity which is transferred between the operator and the receiver via acupuncture needle. Methods : Under the hypothesis, I studied the effects of electric charge in ST37(+) and ST39(-) generated by Apchim (押鍼) manipulation which was stimulated at ST36 point. And compared with data on the changes of electric charge from the hand of the operator during acupuncture stimulation. Electric charge induced via acupuncture needle from the operator may be important factor that causes the changes of electric charge in meridian and acupoint in the receiver. Therefore we investigated the changes of electric charge induced by the operator using Maclab 400 by the following methods. The one was in stable electric circle condition and the other was in unstable electric circle condition. In this experiments, the changes of electric charge from the stimulation type of Apchim manipulation performed in our lab condition in acupuncture therapy was induced at least three factor, one was the difference of bio-potentials between the operator and the receiver of acupuncture therapy, another was the depth of acupuncture insertion from the skin of the receiver the other was an electromyogram of the receiver. Results :The data imply that the first factor should make a capacitance current when the operator touched the acupuncture needle which was inserted in the receiver. Therefore, the results suggest that capacitance currents stimulus in electronic view may be important factor in acupuncture therapy between the operator and the receiver of acupuncture therapy.

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Analysis of Electrical and Optical Characteristics of Silicon Based High Sensitivity PIN Photodiode (Silicon기반 고감도 PIN Photodiode의 전기적 및 광학적 특성 분석)

  • Lee, Jun-Myung;Kang, Eun-Young;Park, Keon-Jun;Kim, Yong-Kab;Hoang, Geun-Chang
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.6
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    • pp.1407-1412
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    • 2014
  • In order to improve spectrum sensitivity of photodiode for detection of the laser at 850 nm ~ 1000 nm of near-infrared wavelength band, this study has produced silicon-based fast film PIN photodiode and analyzed electrical and optical properties. The manufactured device is packaged in TO-18 type. The electrical properties of the dark currents both Anode 1 and Anode 2 have valued of approximately 0.055 nA for 5 V reverse bias, while the capacitance showed 19.5 pF at frequency range of 1 kHz and about 19.8 pF at the range of 200 kHz for 0 V. In addition, the rising time of output signal was verified to have fast response time of about 30 ns for 10 V. For the optical properties, the best spectrum sensitivity was 0.66 A/W for 880 nm, while it was relatively excellent value of 0.45 A/W for 1,000 nm.