• 한국식품영양과학회지
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• 제34권2호
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• pp.176-180
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• 2005

흰쥐를 대상으로 하여 식이 단백질 수준에 따라 칼슘 수준을 달리하여 식이를 공급하여 칼슘 식이효율, 칼슘대사와 관련된 호르몬, 대퇴골의 무게 및 칼슘 함유량, 골밀도를 측정하였다. 실험 식이의 구성은 \circled1 HPNC군-고단백 적정칼슘군(Protein: 400 g/kg diet, calcuim: 0.5%) \circled2 HPLC군-고단백 저칼슘군(Protein: 400 g/kg diet, calcium: 0.1%) \circled3 NPNC군-적정 단백 적정 칼슘군 protein: 200 g/kg diet, calcium: 0.5%) \circled4 NPLC군-적정단백 저칼슘군(protein: 200 g/kg diet, calcium: 0.1%)으로 구별하였다. 실험 종료까지의 체중은 NPLC군에서 가장 많이 증가하였으나, 실험군간의 차이를 나타내지 않았고, 식이 섭취량도 실험군간에 차이를 보이지 않았다. 뇨 칼슘배설량은 고단백군이 적정단백군보다 높은 경향을 나타내었고, HPLC군에서 유의적으로 높은 값을 보였으며 체내 칼슘보유량과 흡수율은 실험군에 따른 차이가 없었다. 뼈형성의 biomarker인 ALP의 활성은 저칼슘 식이군인 NPLC군에서 유의하게 높았고, 고단백 적정칼슘을 섭취한 HPNC군에서 유의적으로 낮았다. 혈액의 PTH 농도는 HPLC군에서 가장 낮게 나타났으며, 소변의 DPD농도는 저칼슘 식이군인 HPLC군과 NPLC군에서 높은 수치로 관찰되었고, HPNC군에서는 유의적으로 낮아졌다. 대퇴골의 건조 전의 습윤무게는 중 100 g당의 무게로 환산했을 때 NPLC군에서 가장 낮았으며 건조 후의 대퇴골의 무게 역시 다른군에 비해 NPLC군에서 가장 낮았다. 대퇴골의 회분 함량은 실험군간의 큰 차이를 나타내지 않았고, 칼슘 함량은 NPLC군과 HPLC군에서 유의하게 낮았다. 대퇴골의 골밀도는 NPNC군에서 가장 높게 나타났으며, NPC군은 가장 낮게 나타났다. 본 연구결과 고단백 저칼슘 식이 섭취시 요중 칼슘 배설량이 가장 많았고, DPD 농도가 다른 군에 비하여 유의적으로 높았으며, 골밀도도 가장 낮게 조사되어 고단백식이 섭취시 칼슘섭취 부족은 칼슘대사에 좋지 못한 결과를 나타냄을 알 수 있었다.이로 볼 때 적절한 단백질과 칼슘 섭취가 골격의 건강을 유지하고 노령화에 따른 골격질환을 예방할 수 있고, 특히 고단백 섭취시에는 칼슘영 양이 부족할 경우 골격 대사를 저해할 수 있으므로 충분한 칼슘 섭 취가 무엇보다도 중요하다고 본다.

• The Korean Journal of Physiology and Pharmacology
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• 제19권1호
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• pp.51-57
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• 2015

The etiology of periodontal disease is multifactorial. Exogenous stimuli such as bacterial pathogens can interact with toll-like receptors to activate intracellular calcium signaling in gingival epithelium and other tissues. The triggering of calcium signaling induces the secretion of pro-inflammatory cytokines such as interleukin-8 as part of the inflammatory response; however, the exact mechanism of calcium signaling induced by bacterial toxins when gingival epithelial cells are exposed to pathogens is unclear. Here, we investigate calcium signaling induced by bacteria and expression of inflammatory cytokines in human gingival epithelial cells. We found that peptidoglycan, a constituent of grampositive bacteria and an agonist of toll-like receptor 2, increases intracellular calcium in a concentration-dependent manner. Peptidoglycan-induced calcium signaling was abolished by treatment with blockers of phospholipase C (U73122), inositol 1,4,5-trisphosphate receptors, indicating the release of calcium from intracellular calcium stores. Peptidoglycan-mediated interleukin-8 expression was blocked by U73122 and 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetrakis (acetoxymethyl ester). Moreover, interleukin-8 expression was induced by thapsigargin, a selective inhibitor of the sarco/endoplasmic reticulum calcium ATPase, when thapsigargin was treated alone or co-treated with peptidoglycan. These results suggest that the gram-positive bacterial toxin peptidoglycan induces calcium signaling via the phospholipase C/inositol 1,4,5-trisphosphate pathway, and that increased interleukin-8 expression is mediated by intracellular calcium levels in human gingival epithelial cells.

• Journal of Yeungnam Medical Science
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• 제5권2호
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• pp.59-69
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• 1988

Strontium은 calcium파 같은 2가 양이온으로서 평활근에서 calcium과 치환되어 평활근을 수축시킬 수 있으며, 골격근에서도 calcium과 치환되어 이를 수축시킬 수 있는 것으로 알려져 있다. 그러나 심근에서는 strontium이 calcium과 치환되어 심근을 수축시킬 수 있다는 보고가 있으나 그 기전에 대해서는 잘 알려져 있지 않다. 이에 저자는 심근에서 strontium이 calcium과 치환되어 사용될 수 있는지를 관찰하고, 그 기전을 알아보기 위해서 다음과 같은 실험을 하였다. 체중 200 g m 내지 230 g m의 흰쥐(Sprague-Dawley)의 심장을 적출하여 Langendorff씨 심관류 장치에 현수한 후 자율 수축운동을 하는 적출심장의 좌심실 내에 balloon을 넣어 수축성, 좌심실압 및 심박동수의 변화를 측정하였다. 먼저 strontium 치환용액의 관류시 나타나는 좌심실압, 수축성 및 심박동수의 변화를 관찰하였다. 그리고 심근을 흥분시키는 norepinephrine과 억제하는 verapamil이 포함된 strontium 치환용액을 관류할 때 나타나는 수축성, 좌심실압 및 심박동수의 변화를 관찰하여 다음과 같은 결과를 얻었다. 1. 저 calcium 관류용액을 관류 하였을 때 심근수축력은 현저히 억제되었으며, strontium을 첨가하여 calcium파 strontium의 농도의 합이 정상 관류용액의 calcium농도 (2.43mM)가 되게 하여 관류 하였을 때 심근 수축력은 정상 calcium농도의 관류용액을 관류했을 때의 심근 수축력에 비해 억제되지 않았다. 2. 관류용액 내의 calcium을 strontium으로 완전치환시 심정지가 유발되었으며, 이때 관류용액내에 calcium이나 strontium을 첨가 했을 때도 심근수축력은 회복되지 않았다. 3. Norepinephrine 유발 양성변력성 작용은 정상관류용액, 저calcium 관류용액 및 strontium 치환용액 모두에서 농도에 비례한 증가 양상을 보였다. Strontium 치환용액에서는 정상 관류용액에서와 차이가 없었으나, 저calcium용액에서는 고농도의 norepinephrine의 수축력 증가작용은 정상 용액에서와 차이가 없었고 저농도의 norepinephrine의 수축력 증가작용은 정상용액에서 보다 유의하게 낮았다. 4. verapamil은 calcium 용액 뿐만 아니라 strontium 치환용액에서도 심근 수축력을 현저히 감소시켰다. 이상의 실험 결과로 미루어 볼 때 strontium은 calcium과 대치되어 심근을 수축시킬 수 있으며 calcium과 같은 자격으로 norepinephrine 유발 양성 변력성작용에 참여하고 verapamil에 의해서는 calcium과 같은 양상으로 그 이동이 억제된다고 사료된다.

• 한국식품영양과학회지
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• 제42권4호
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• pp.497-504
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• 2013

본 연구에서는 4종의 천연칼슘소재를 이용하여 칼슘 이온화 특성 및 in vitro 칼슘 이용률을 조사하였다. 천연칼슘소재는 8.0%(w/v) 첨가농도까지 칼슘용해량과 칼슘이온 함량은 증가하였으나 이상의 농도에서는 큰 변화는 없었다. 또한 이온화율은 약 90%로, 칼슘소재와 첨가농도에 따른 큰 차이는 나타나지 않았다. 칼슘의 이온화에 용해온도는 큰 영향이 없었으며, 용해 18시간째 가장 높은 칼슘이온 함량을 나타났다. 칼슘액 중 BS의 in vitro 칼슘 이용률은 67.3%로 가장 높게 나타났으며, AS는 62.4%, DS는 57.9%, CS는 57.5%로 시판 칼슘제 및 천연칼슘소재에 비해서 약 2배 정도 높게 나타났다. 시판 우유, 두유 및 오렌지 주스의 in vitro 칼슘 이용률을 조사한 결과 탄산칼슘보다 이온화 칼슘액을 첨가한 구간에서 2배 이상 높게 나타났다. 따라서 천연칼슘소재의 이온화 칼슘은 생체 이용율이 높은 다양한 식품소재로 활용이 기대된다.

• Asian-Australasian Journal of Animal Sciences
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• 제12권3호
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• pp.422-428
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• 1999

The mineral status of native goats and forage species, namely; Cynodon plectostachyus, Pennisetum purpureum. Eleusine indica, Cynodon dactylon, Calopogonium muconoides, Centrosema pubescens, Leucaena leococephala, and Mimosa pudica in lahar affected areas of Concepcion, Tarlac, Philippines were determined. Forage and blood samples were collected six times in 1996-97, and analyzed for calcium, phosphorus, magnesium, sulfur, copper, iron, molybdenum, selenium, and zinc. Forage calcium and sulfur are non-limiting. Most species had low phosphorus, copper and selenium, while some had magnesium and zinc levels lower than the critical limit because of low mineral content and high percolation rate of lahar deposits. Iron and molybdenum were in excess. The effect of seasonal variation was observed only in copper, sulfur and iron. Average blood mineral concentration of the animals was above critical limit, but there were no significant differences between seasons. All the animals had plasma phosphorus and magnesium above critical level; but 20 % had low copper, zinc and selenium especially in dry season possibly due to insufficient amount of these elements and excessive molybdenum and iron in most forage. Conversely, calcium in forage was high; but 40 % of the animals had low plasma calcium concentration. Although no clinical signs of mineral deficiencies were observed, supplemental feeding would be important since the condition of the pasture in lahar-laden areas is not expected to improve in the next five years. Intensified use of L. leucocephala with better mineral profile would be ideal.

• The Korean Journal of Physiology and Pharmacology
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• 제1권5호
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• pp.537-546
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• 1997

It has been postulated that the intracellular taurine is co-transported with $Na^+$down a concentration gradient and prevents the intracellular accumulation of sodium. It is therefore, expected that an elevated level of intracellular taurine prevents the sodium-promoted calcium influx to protect the cellular damages associated with sodium and calcium overload. In the present study, we evaluated the effects of intra- and extracellular taurine on the myocardial $Na^+$and$Ca^{++}$ contents and the cardiac functions in isolated rat hearts which were loaded with sodium by monensin, a $Na^+-ionophore$. Monensin caused a dose-dependent increase in intracellular $Na^+$ accompanied with a subsequent increase in intracellular $Ca^{++}$ and a mechanical dysfunction. In this monensin-treated heart, myocardial taurine content was decreased with a concomittent increase in the release of taurine. The monensin-induced increases in intracellular $Na^+$, $Ca^{++}$ and depression of cardiac function were prevented in the hearts of which taurine content had been increased by high-taurine diet. Conversely, in the hearts of which taurine concentration gradient had been decreased by addition of taurine in the perfusate, the monensin-induced increases in $Na^+$, $Ca^{++}$ and functional depression were accelerated. These results suggest that taurine, depending on the intra-extracellular concentration gradient, can affect intracellular sodium and calcium concentrations, and that an increased intracellular taurine may play a role in protection of myocardial dysfunction associated with the sodium and calcium overload.

• 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
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• 제10권1호
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• pp.15-24
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• 1976

The action of aconite on the sodium plus potassium activated ATPase activity in the rabbit red cell membrane has been investigated and the experiments were also designed to determine the mechanism of action of aconite on the ATPase activity. The following results were observed. 1. The activity of the NaK ATPase from red cell membrane is stimulated by aconite, and the concentration of aconite for maximal activity is about 80 mg%. The pH optimum for the aconite sensitive component is 8.0. 2. The activating effect of aconite on the ATPase, with a given concentration of sodium in the medium, is increased by raising the potassium concentration but activity ratio is decreased. 3. The activating effect of aconite on the ATPase, with a given concentration of potassium in the medium, is increased by raising the sodium concentration but activity ratio is decreased. 4. The action of aconite on the ATPase activity is inhibited by calcium ions and the effect of inhibition is increased by small amounts of calcium but decreased by larger amounts. 5. The activating effect of aconite on the ATPase was not related to the sulfhydryl group of cysteine, the amino group of lysine, the hydroxyl group of threonine or the imidazole group of histidine. 6. The action of aconite on the ATPase activity is due to carboxyl group of the enzyme of NaK ATPase.

• The Korean Journal of Physiology
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• 제12권1_2호
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• pp.25-34
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• 1978

The action of theobromine on the sodium plus potassium activated ATPase activity In the rabbit red cell membrane has teen investigated and the experiments were also designed to determine the mechanism of action of theobromine on the ATPase activity. The following results were observed. 1. The activity of the NaK ATPase from red fell membrane is stimulated by theobromine, and the concentration of theobromine for maximal activity is about 3mM. 2. The activating effect of theobromine on the ATPase, with a given concentration of potassium in the medium, is increased by raising the sodium concentration but activity ratio is decreased. 3. The activating effect of theobromine on the ATPase, with a given concentration of sodium in the medium. is increased by the raising the potassium concentration but activity ratio is decreased. 4. The NaK ATPase activity is increased by small amounts of calcium but decreased by larger amounts. The activity of the enzyme by theobromine is increased by small amounts of calcium but decreased by larger amounts. 5. The activating effect of theobromine on the ATPase was not related to the hydroxyl group of threonine and imidazole group of histicline. 6. The activating effect of theobromine on the ATPase is due to sulfhydryl group, amino group and carboxyl group of the enzyme of NaK ATPase.

• The Korean Journal of Physiology
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• 제11권1호
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• pp.11-20
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• 1977

The action of pilocarpine on the sodium plus potassium activated ATPase activity in the rabbit red cell membrane has been investigated and the experiments were also designed to determine the mechanism of action of pilocarpine on the ATPase activity. The following results were observed. 1. The activity of the NaK ATPase from red cell membrane is stimulated by pilocarpine, and the concentration of pilocarpine for maximal activity is about 3 mM. The pH optimum for the pilocarpine sensitive component is 8.0. 2. The activating effect of pilocarpine on the ATPase, with a given concentration of sodium .in the medium, is increased by raising the potassium concentration but activity ratio is decreased 3. The activating effect of pilocarpine on the ATPase, with a given concentration of Potassium in the medium, is increased by raising the sodium concentration but activity ratio is decreased 4. The NaK ATPase activity is increased by small amounts of calcium but decreased by 'larger amounts. The activity ratio of the enzyme by pilocarpine is decreased by small amounts .of calcium but decreased by larger amounts. 5. The activating effect of pilocarpine on the ATPase was not related to the sulfhydryl group of cysteine, the hydroxyl group of threonine or the imidazole group of histidine. 6. The activating effect of pilocarpine on the ATPase is due to amino group and carboxyl group of the enzyme of NaK ATPase