• 한국독성학회:학술대회논문집
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• 한국독성학회 2003년도 춘계학술대회 논문집
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• pp.73-74
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• 2003

Familial form of Alzheimer's disease (FAD) is caused by mutations in presenilin-1 and presenilin-2 (PS2). PS1 and PS2 mutation are known to similar effects on the production of amyloid $\beta$ peptide (A$\beta$) and cause of cell death in the Alzheimer's brain. The importance of the alternation of calcium homeostasis in the neuronal cell death by PS1 mutation in a variety of experimental system has been demonstrated. (omitted)

• BMB Reports
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• 제43권3호
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• pp.158-163
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• 2010

Calumenin is a multiple EF-hand $Ca^{2+}$-binding protein located in the endo/sarcoplasmic reticulum of mammalian hearts. Calumenin belongs to the CREC family of $Ca^{2+}$-binding proteins having multiple EF-hands. $Ca^{2+}$ homeostasis in the sarcoplasmic reticulum (SR) of mammalian hearts is maintained by RyR2, SERCA2 and other associated SR resident proteins. Evidence suggests that calumenin interacts with RyR2 and SERCA2, and therefore changes in the expression of calumenin could alter $Ca^{2+}$ cycling in mouse heart. In this review, current knowledge of the biochemical and functional roles of calumenin in mouse heart is described.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2002년도 제9회 학술 발표회 프로그램과 논문초록
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• pp.56-56
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• 2002

Muscle contraction and relaxation are regulated by the sarcoplasmic reticulum (SR)-mediated $Ca^{2＋}$ release and $Ca^{2＋}$ uptake. The SR functions are closely related with the proteins residing in the SR such as ryanodine receptor, $Ca^{2＋}$-ATpase, calsequestrin, triadin and junctin. In an effort to further identify important functional SR proteins, experiments of sucrose-density gradient of SR fractionation, concanavalin A treatment, 2D gel electrophoresis, $^{45}$ Ca$^{2+}$ overlay, Strains-all staining, and peptide finger printing (PFP) were carried out.(omitted)d)

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2001년도 학술 발표회 진행표 및 논문초록
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• pp.61-61
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• 2001

Triadin is a ryanodine receptor and calsequestrin binding protein located in junctional sarcoplasmic reticulum of striated muscles. In the present study, mouse cardiac triadin cDNAs have been identified by cDNA library screening and RT-PCR. The deduced aa sequences show that the three isoforms consist of 277, 293 and 305 aa giving rise to the molecular weights of approximately 31,414,33,066, and 34,328 respectively.(omtted)

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-1
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• pp.94-95
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• 2003

Local cytosolic rises of $Ca^{2+}$ appears to be critical in the regulation of many cellular activities, including muscle contraction, neurotransmitter secretion, and cell death. Cardiac $Ca^{2+}$ signaling similarly begins with discrete and localized rises of $Ca^{2+}$($Ca^{2+}$ sparks) triggered by $Ca^{2+}$ current ($I_{Ca}$). The large local releases of $Ca^{2+}$ in turn modulate L-type $Ca_{v}$1.2( ${\alpha}_{1C}$ $Ca^{2+}$ channels, suggesting that discrete $Ca^{2+}$ cross-signaling may occur in the micro-domains of ${\alpha}_{1C}$/ryanodine receptors (RyRs). (omitted)

• Journal of Animal Science and Technology
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• 제44권1호
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• pp.13-22
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• 2002

한우의 성장단계 특이발현 유전자를 탐색하기 위하여, 본 연구에서는 유전자의 발현 유무 및 발현정도의 차이를 나타내는 유전자를 분리하는데 있어 가장 강력한 수단으로 알려진 subtractive cDNA hybridization 기법을 이용하여 한우 등심조직으로부터 12개월령 및 24개월령 특이적인 subtractive cDNA library를 제작하였다. 성장단계 특이적인 유전자를 탐색하기 위하여, 6, 12 및 24개월령 cDNA를 사용하여 reverse northern blot 분석을 실시하였으며, 6개월령 cDNA probe에 대하여 특이적인 signal을 나타낸 3개의 clone은 EPV 20, Ca2+ ATPase, 및 TCTP 유전자와 유사성을 나타내었다. 12개월령 cDNA probe에 대하여 특이적인 signal을 나타낸 9개의 cDNA clone은 각각 VCP, HSP 70, aldolase A, MSSK1, GM-2 activator protein, ryanodine receptor, acidic ribosomal phosphoprotein p1, ADP/ATP translocase T1 및 UCP 2 유전자와 높은 homology를 가지고 있었다. 또한 2개의 clone이 각각 12개월령 및 24개월령 cDNA probe에 대하여 특이적인 signal을 나타내었는데, 12개월령 cDNA probe에 대해서만 signal을 나타낸 clone은 ferrochelatase 유전자와 유사하였으며, 24개월령 probe에 대해서만 signal을 나타낸 clone은 ADRP 유전자와 유사하였다. 이상에서와 같이, 본 연구에서 제작한 성장단계 특이적인 subtractive cDNA library를 분석하여 14종의 유전자를 한우 성장단계 특이 발현 후보 유전자로 선정하여 염기서열을 분석하였으며, 이외에도 성장단계에 있어 특이적으로 발현될 것으로 추정되는 cDNA 클론의 염기서열을 분석하였다.

• The Korean Journal of Physiology
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• 제24권1호
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• pp.77-90
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• 1990

There have been conflicting reports concerning the effect of Panax ginseng on the contractility of vascular smooth muscle, i.e., Panax ginseng extract has been reported to cause relaxation, contraction or to have no effect on the tension of vascular smooth muscle. A further investigation of $Ca^{++}$ stores which supply $Ca^{++}$ for contraction of vascular smooth muscle is needed to understand the underlying mechanisms of this conflicting effect of ginseng alcohol extract (GAE). The present study was intended to examine the sources of calcium mobilized for contraction of vascular smooth muscle by GAE. Aortic ring preparations were made from the rabbit thoracic aorta and endothelial cells were removed from the ring. The contractility of the aortic ring was measured under various experimental conditions and $Ca^{++}$ flux across the membrane of aortic ring and the sarcoplasmic reticulum and mitochondria were measured with a calcium selective electrode. The result were summarized as follows; 1) At low concentration of extracellular $Ca^{++}$, GAE increased the contractility of vascular smooth muscle in dose-dependent fashion except high concentration $Ca^{++}$ (1 mM). 2) In the presence of ryanodine, GAE still increased contractility of vascular smooth muscle as much as control group, but in the presence of caffeine, GAE increased it significantly. i.e. Their effects seemed to be additive. 3) In the presence of verapamil+lanthanum, and verapamil+lanthanum+ryanodine, the contractility of the vascular smooth muscle was decreased, but a dose dependent increase in vascular tension was still demonstrated by GAE although total tension was low. 4) GAE increased $Ca^{++}$ efflux from vascular smooth muscle cells, but have no effect on $Ca^{++}$ influx. 5) GAE increased $Ca^{++}$ efflux from sarcoplasmic reticulum and mitochondria vesicles. From the above results, it may be concluded that GAE increased the release of $Ca^{++}$ from sarcoplasmic reticulum, mitochondria or other intracellular $Ca^{++}$ stores of vascular smooth muscle, but it does not increase $Ca^{++}$ influx across the plasma membrane.

• Toxicological Research
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• 제18권4호
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• pp.355-362
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• 2002

Pathophysiological elevation of intracellular calcium concentration ($[Ca^{2+}]_1$) in the neuron has been considered as an important responsible factor in the neuronal cell damages. However the mechanism of increase of $[Ca^{2+}]_1$ and the relationship between $[Ca^{2+}]_1$ level and cytotocixity have not been fully demonstrated. In the present study, real-time alteration of $[Ca^{2+}]_1$and cellular response (cell damages) in the pheochromocytoma cells (PC12) stimulated by glutamate were investigated. Glutamate dose dependently decreased cell viability determined propidium iodide fluorescence method and morphology change. Conversely related with cell damages, glutamate dose dependently increased the level of［Ca$^{2+}$］$_{i}$ . To investigate the mechanism of glutamate-induced increase of $[Ca^{2+}]_1$,$[Ca^{2+}]_1$, was first measured in the cell cultured in calcium free media and in the presence of dantrolene, an inhibitor of calcium release from ryanodine receptor located in endoplasmic reticulum (ER). Similar to the increase$[Ca^{2+}]_1$ in the calcium-containing media, glutamate dose dependently increased $[Ca^{2+}]_1$ in the cell cultured in free calcium media. However pretreatment (2 hr) with 20~50 $\mu\textrm{M}$ dantrolene substantial lowered glutamate-induced increase of $[Ca^{2+}]_1$, suggesting that release of calcium from ER may be major sourse of increase of $[Ca^{2+}]_1$ in PC12 cells. Dantrolene-induced inhibition of $[Ca^{2+}]_1$ resulted in recovery of cytotoxicity by glutamate. Relevance of N-methy-D-aspartate (NMDA) receptor, a type of glutamte receptor on glutamate-induced incense of $[Ca^{2+}]_1$,$[Ca^{2+}]_1$ was also determined in the cells pretreated (2 hr) with NMDA receptor antagonist MK-80l. Glutamate-induced increase of $[Ca^{2+}]_1$ was reduced by MK-801 dose dependently. Furthermore, glutamate-induced cytotoxicity was also prevented by MK-80l. These results demonstrate that glutamte increase $[Ca^{2+}]_1$ dose dependently and thereby cause cytotoxicity. The increase of $[Ca^{2+}]_1$ may release from ER, especially through ryanodine receptor and/or through NMDA receptor Alteration of calcium homeostasis through disturbance of ER system and/or calcium influx through NMDA receptor could contribute glutamate-induced cell damages.s.

• The Korean Journal of Physiology and Pharmacology
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• 제26권6호
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• pp.531-540
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• 2022

Group 1 metabotropic glutamate receptors (mGluRs) can positively affect postsynaptic neuronal excitability and epileptogenesis. The objective of the present study was to determine whether group 1 mGluRs might be involved in synaptically-induced intracellular free Ca²⁺ concentration ([Ca²⁺]_i) spikes and neuronal cell death induced by 0.1 mM Mg²⁺ and 10 µM glycine in cultured rat hippocampal neurons from embryonic day 17 fetal Sprague-Dawley rats using imaging methods for Ca²⁺ and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays for cell survival. Reduction of extracellular Mg²⁺ concentration ([Mg²⁺]_o) to 0.1 mM induced repetitive [Ca²⁺]_i spikes within 30 sec at day 11.5. The mGluR5 antagonist 6-Methyl2-(phenylethynyl) pyridine (MPEP) almost completely inhibited the [Ca²⁺]_i spikes, but the mGluR1 antagonist LY367385 did not. The group 1 mGluRs agonist, 3,5-dihydroxyphenylglycine (DHPG), significantly increased the [Ca²⁺]_i spikes. The phospholipase C inhibitor U73122 significantly inhibited the [Ca²⁺]_i spikes in the absence or presence of DHPG. The IP₃ receptor antagonist 2-aminoethoxydiphenyl borate or the ryanodine receptor antagonist 8-(diethylamino)octyl 3,4,5-trimethoxybenzoate also significantly inhibited the [Ca²⁺]_i spikes in the absence or presence of DHPG. The TRPC channel inhibitors SKF96365 and flufenamic acid significantly inhibited the [Ca²⁺]_i spikes in the absence or presence of DHPG. The mGluR5 antagonist MPEP significantly increased the neuronal cell survival, but mGluR1 antagonist LY367385 did not. These results suggest a possibility that mGluR5 is involved in synaptically-induced [Ca²⁺]_i spikes and neuronal cell death in cultured rat hippocampal neurons by releasing Ca²⁺ from IP₃ and ryanodine-sensitive intracellular stores and activating TRPC channels.

• The Korean Journal of Physiology and Pharmacology
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• 제4권5호
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• pp.417-425
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• 2000

The underlying mechanism commonly applicable for both the positive and negative force-frequency relationships (FFR) was pursued in left atria (LA) of rat and rabbit. The species differences in the roles of $Na^+/Ca^{2+}$ exchanger and sarcoplasmic reticulum (SR), which are major intracellular $Ca^{2+}$ regulatory mechanisms in the heart, were examined in the amplitude accommodation to the frequency that changed from 3 Hz to the variable test frequencies for 5 minutes in the electrically field stimulated left atria (LA) of rat and rabbit. Norepinephrine strongly increased the frequency-related amplitude accommodation in both of rat and rabbit LA, while monensin, oubain or the reduced $Na^+$ and 0 mM $Ca^{2+}$ containing Tyrode solution increased the frequency-related amplitude accommodation only in the rabbit LA. Monenisn was also able to increase the frequency-related amplitude accommodation only in 1-day old rat LA but not in 4-week old rat LA that had 75% less $Na^+/Ca^{2+}$ exchanger with 97% higher SR than 1-day old rat LA. Taken together, it is concluded that the differences in the prevalence between myocardial $Na^+/Ca^{2+}$ exchanger and SR in the amplitude accommodation to the frequency-change determine the difference in the FFR between rat and rabbit heart.