• 대한약리학회지
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• 제32권1호
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• pp.13-21
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• 1996

세포내 칼슘농도는 신경세포의 다양한 기능에 매우 중요한 역할을 하고 있다. 본 연구에서는 일차배양한 마우스 소뇌과립세포에서 니코틴성 아세틸콜린 수용체가 특정 발생단계에 발현되고 세포내 칼슘의 농도조절에 관여하는 것을 관찰하였다. 니코틴에 의한 세포내 칼슘농도의 변화는 $^{45}Ca^{2+}$나 fura-2를 사용하여 형광법으로 측정하였다. 니코틴은 마우스 소뇌과립세포내 칼슘의 농도를 최대한 증가시키는 것으로 보인다. 반면에 일차배양한 Glia 세포들에서는 $^{45}Ca^{2+}$ 농도를 증가시키지 않았다. 세포내 칼슘농도에 미치는 니코틴의 효과는 NMDA 수용체에 대한 길항제에 의하여 억제되었다. 또한 Glutamate pyruvate transminase (GPT)를 사용하여 배양액의 글루타민산을 제거하면 니코틴효과가 소실되는 것이 관찰되었다. 이러한 결과는 니코틴에 의한 세포내 칼슘농도의 변화가 세포에서 유리된 글루타민산에 의한 간접적인 효과임을 암시한다. Fura-2를 사용한 형광법으로 실험한 결과 니코틴은 two phase로 세포내 칼슘농도를 증가시키는 것을 보여주었다. NMDA 수용체 길항제와 GPT는 단지 후기 plateau상만 억제하였다. 따라서 본 연구결과는 니코틴이 직접 니코틴성 아세틸콜린 수용체를 자극하여 일시적으로 세포내 칼슘농도를 증가시키고 글루타민산을 유리하여 NMDA 수용체를 활성화시킴으로써 세포내 칼슘농도를 지속적으로 증가시키는 것으로 보여진다. 이러한 결과는 니코틴성 아세틸콜린 수용체가 특정한 발생과정에 발현되어 세포내 칼슘농도 조절에 관여함으로써 신경발생과정에서 중요한 역할을 할 수 있음을 보여주고 있다. state를 나타내는 것을 알 수 있다. 또한 $[^3H]DPCPX$를 이용한 competitive binding assay에서 0.1 mM GTP는 효현제인 PIA의 apparent affinity를 감소시켰으며, DPCPX의 apparent affinity는 증가시키고, CGS-15943에는 아무런 영향을 미치지 않았다. 이것은 상기의 $[^{35}S]GTP_{\gamma}S$ binding의 결과를 뒤받침해 주는 결과라고 생각된다.요한 역할을 할 수 있으리라 사료된다.X>$Ca^{2+}$에 의하여 활성화되는 $K^+$ 통로를 개방시킴으로 세포내 $Ca^{2+}$을 감소시켜 뇌 기저동맥의 이완반응을 매개하는 것으로 사료된다. 함량을 조정하므로, 흉선세포의 apoptosis에 억제적으로 작용할 수 있음을 시사하는 것으로 사료된다. 영양액에 의하여는 회복됨을 볼 수 있었으며 $Mg^{++}$ 증가 영양액에서는 억제, TTX 동시 투여시에는 완전히 소실되었다. 이상의 실험결과로 흰쥐 해마에서 $A_1-adenosine$ 수용체를 통한 adenosine의 NE 유리 감소는 TEA 및 4AP에 예민한 $K^+$-통로가 관여하고 여기에는 세포외액의 Ca^{++}의 농도가 중요한 인자의 하나로 관여 하는 것으로 사료된다. 영상의 질을 크게 향상 시켜 줌으로 비가역 3구획모델에서의 PGA방법을 대체할 새로운 파라메터 영상구성방법으로 적합할 것이다.관계되며, YH439는 중금속으로 유도된 조직독성에 방어효과가 있음을 지지한다.총 아미노산의 순은

• 한국균학회지
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• 제16권4호
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• pp.247-252
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• 1988

야생형(野生型)인 만가닥버섯(Lyophyllum ulmarium ASI 8007)의 원형질체(原形質體)로부터 분리(分離)한 염색체(染色體)를 영양요구주(營養要求株)인 잔나비걸상버섯(Ganoderma applanatum ASI 7-18; cys met)의 원형질체내(原形質體內)에 $PEG+CaCl_2$로 섭입(攝入)하였다. 형질전환주(形質轉煥株)는 microtransgenome과 macrotransgenome type으로 전자(前者)는 느리고 불안정성(不安定性)인 균사생장(菌絲生長), 후자(後者)는 아주 빠른 안정성(安定性)인 균사생장(菌絲生長)이 있으며, 균사(菌絲)가 양친(兩親)보다 굵었으며 GCM+benomyl에서 균총분리(菌叢分離)가 일어났다. 이들을 전기영동으로 esterase 동위효소(同位酵素) 패턴을 조사한 결과 양친에 비하여 위치가 다르게 나타났다.

• The Korean Journal of Physiology
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• 제29권2호
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• pp.269-277
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• 1995

Membrane vesicles were prepared by differential centrifugation from epithelial cells of porcine trachea. Total activity of microsomal ATPases was measured spectrophotometrically by a coupled enzyme assay. The steady-state activity of the enzyme was $329{\pm}10$ nmol/min mg protein. Thapsigargin, a specific antagonist of intracellular $Ca^{2+}-ATPase$, inhibited about 50% of the activity, leaving $178{\pm}18\;nmol/min .mg$ protein (n=6), indicating that the $Ca^{2+}-ATPase$ is one of the major microsomal ATPases. The microsomes used in this study appeared to be tight-sealed vesicles since they showed saturation in $^{45}Ca^{2+}$ uptake experiments. Inositol 1,4,5-trisphosphate $InsP_{3}, 4\;{\mu}M$, an agonist of $InsP_{3}$-sensitive $Ca^{2+}$ release channel ($InsP_{3}$, receptor), and Ca-ionophore A23187 $(10\;{\mu}M)$ induced $^{45}Ca^{2+}$ releases of 20% and 50% of stored $^{45}Ca^{2+}$, respectively. The addition of $(10\;{\mu}M\;InsP_{3}$ also increased the microsomal ATPase activity from $282{\pm}8$ nmol/min mg protein to $334{\pm}21$ nmol/min . mg protein in the intact vesicles. Similar increase in the activity was observed by making microsomes leaky (uncoupling) using the Ca-ionophore A23187. ;$InsP_{3}-induced$ effects were blocked by either thapsigargin or heparin suggesting that: 1) the $InsP_{3}-induced$ increase in ATPase activity is mediated by microsomal $Ca^{2+}-ATPase$, and 2) dissipation of $Ca^{2+}$ gradient across the microsomal membrane is responsible for the $InsP_{3}-induced$ effect. In order to test the dependence of the $Ca^{2+}-ATPase$ activity on the activity of $InsP_{3}-induced$ the activity of ATPases was monitored in various concentrations of free $Ca^{2+}$ using $EGTA-Ca^{2+}$ buffers. The $Ca^{2+}$-dependent biphasic change is the well-known character of $InsP_{3} receptor but not of microsomal $Ca^{2+}-ATPase$ in non-excitable cells; however, the activity of microsomal ATPase appeared biphasic and a maxim진 activity of $397{\pm}36nmol/min\;.mg$ protein was obtained in the solution containing 100 nM free $Ca^{2+}$. Below or above this concentration, the activity of ATPases was lower. These results strongly support a positive correlation of microsomal $Ca^{2+}-ATPase$ to the $InsP_{3}$ receptors in epithelial microsomes.

• The Korean Journal of Physiology
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• 제24권2호
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• pp.377-388
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• 1990

Ca movements during the late plateau phase in rabbit atrium implicate Na-Ca exchange. In single atrial cells isolated from the rabbit the properties of the inward current of Na-Ca exchange were investigated using the whole cell voltage clamp technique. The inward currents were recorded during repolarization following brief 2 ms depolarizing pulse to +40 mV from a holding potential of -70 mV. Followings are the results obtained: 1) When stimulated every 30 sec, the inward currents were activated and reached peak values $6{\sim}12\;ms$ after the beginning of depolarizing pulse. The mean current amplitude was 342 pA/cell. 2) The current decayed spontaneously from the peak activation and the timecourse of the relaxation showed two different phases: fast and slow phase. 3) The recovery of the inward current was tested by paired pulse of various interval. The peak current recovered exponentialy with a time course similar to that of Ca current recovery. 4) Relaxation timecourse was also affected by pulse interval and time constant was reduced almost linearly according to the decrease of pulse interval between 30 sec and 1 sec. 5) The peak inward current was increased by long prepulse stimulation, Bay K, isoprenaline or c-AMP. 6) The relaxation time constant of the inward current was prolonged by Bay K or c-AMP, and shortened by isoprenaline. From the above results, it could be concluded that increase of the calcium current potentiates and prolongs intracellular calcium transients, while shortening of the timecourse by isoprenaline or short interval stimulations might be due to the facilitation of Ca uptake by SR.

• 유기물자원화
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• 제6권2호
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• pp.59-67
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• 1998

이 연구는 대규모의 pilot plant에서 생산된 음식물찌꺼기 퇴비의 시용에 따른 작물(열무, 상추)에 의한 염류의 흡수와 토양의 화학적 특성 변화를 조사하기 위하여 수행되었다. 일반적으로 음식물찌꺼기 퇴비(FWC)는 전기전도도(EC)가 높고 Na, K, Ca 그리고 Mg와 같은 많은 염류를 함유하고 있다. 이러한 FWC가 토양에 시용될 경우 토양의 염류집적과 작물의 생육저해 가능성을 검증하지 않으면 안된다. FWC를 건물중으로 1/5,000a pot에 0, 20, 40, 80 그리고 160Mg/ha의 비율로 시용한 후 60일 동안 작물을 재배하여 토양의 pH와 EC, 작물에 의한 염류의 흡수를 조사하여 얻어진 결과를 요약하면 다음과 같다. 1. 열무와 상추를 재배한 후 토양의 pH는 증가하였으며, EC는 감소하였다. 2. Na와 K의 흡수량은 FWC의 시용에 의해 약간 증가하였다. Ca의 흡수량에 있어서, 열무와 상추는 각각 감소, 증가하였다. 열무에서 Mg의 흡수량은 40Mg/ha 시용했을 때 가장 높았으며, 상추에서는 FWC의 시용에 따라 지속적으로 증가하였다.

• 한국토양비료학회지
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• 제21권4호
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• pp.422-425
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• 1988

핵분열생성물중(核分裂生成物中) 토양(土壤)에의 흡착(吸着)이 용이하고 식물체내(植物體內) 이행성(移行性)이 높은 $Sr^{90}$의 답토양별(畓土壤別) 수도체내흡수(水稻體內吸收)에 대한 석회시용(石灰施用) 효과(效果)를 조사하여 다음과 같은 결과를 얻었다. 석회시용(石灰施用)에 의한 수도(水稻)의 수량증가(收量增加)는 150kg/10a 까지 인정할 수 있었으며 석회시용량(石灰施用量)의 증가(增加)에 따라 Ca 을 제외한 대부분의 양분흡수(養分吸收)가 억제(抑制)되었다. 수도(水稻)의 $Sr^{90}$의 흡수(吸收)는 300kg/10a까지의 석회시용(石灰施用)에 의해 억제효과(抑制效果)가 있었고 치환성 Ca함량이 낮고 pH가 낮은 산성토양(土壤)일수록 수도(水稻)의 $Sr^{90}$흡수량(吸收量)이 높았으며 따라서 석회시용(石灰施用) 효과(效果)도 컸다.

• Journal of Microbiology and Biotechnology
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• 제4권2호
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• pp.155-159
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• 1994

Two Zymomonas mobilis strains (ZM63 and ZM6307), containing both lactose and galactose operons, were constructed. $\beta$-Galactosidase and galactokinase assays indicated that both operons were expressed in both strains. The transport systems available for lactose uptake by Zymomonas mobilis were investigated using $^{14}C$-labelled lactose. After the outer membrane, which was considered to be a possible barrier to lactose uptake, was disrupted by treatment with EDTA and $Ca^{2+}$ ions, some increase in lactose uptake was observed in ZM6306 ($lac^+$) and ZM6307 ($lac^+\;gal^+$), but not in the parent, ZM6. This suggested that the outer membrane of Zymomonas mobilis acts as a barrier to lactose uptake to some degree, and also that the lactose permease is operational in Zymomonas mobilis.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1998년도 학술발표회
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• pp.29-29
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• 1998

Previously, we reported two types of vanadate-sensitive ATPases in the micro somes of tracheal epithelial cells, a high-affinity one and a low-affinity one. The low affinity vanadate-sensitive (LAVS) ATPase was sensitive to thapsigargin and cyclopiazonic acid, specific antagonists of ER-type Ca$\^$2＋/-ATPase, and mediated microsomal $\^$45/Ca$\^$2+/ uptake, implying that the LAVS-ATPase is an ER/SR-type Ca$\^$2+/-ATPase.(omitted)

• 한국수산과학회지
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• 제49권2호
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• pp.184-189
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• 2016

We investigated physiological changes in the freshwater cichlid, fish Maylandia lombardoi in response to different calcium concentrations in rearing water. Four different calcium concentrations (0, 2, 4 and 8 mM) were prepared in rearing water by the addition of ionized calcium (CaO) to examine the effect of various calcium concentrations in rearing water on physiological changes in the cichlid fish, M. lombardoi. Total calcium concentrations in plasma and body increased in a calcium concentration-dependent manner and reached the maximum at 8-mM calcium concentration. Stress-related cortisol was significantly decreased in the 8-mM group compared to the control group (0 mM). Lysozyme activity also significantly decreased in the 8-mM group. These results suggest that CaO in rearing water increases calcium uptake in fish and affects the body by decreasing stress and improving immunity in fish.

• 대한약리학회지
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• 제8권1호
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• pp.67-75
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• 1972

Many studies on the mechanism of the inotropic action of cardiac glycosides have shown the possible intimate relationship between the mobilization of intracellular calcium and inotropic effect. Evidence obtained from recent studies suggests that cardiac glycosides may increase the intracellular $Ca^{++}$ concentration through the release of this ion from cellular or intracellular membrane. It seemed imperative to study the effect of ouabain on the interaction between mitochondria and $Ca^{++}$, because mitochondria are known to have a rather powerful $Ca^{++}$ pump mechanism which may have an important role on the regulation of intracellular $Ca^{++}$ concentration. The present investigations was made into the effect of ouabain on $Ca^{++}$ untake of mitochondria in the presence of ATP and its dependence on $K^+$ and $Na^+$ in the medium. The results are summarized as follows: 1. The rate of rise in the turbidity of superprecipitation was solely influenced by ionic strength of the medium, not by the species of ion, i.e. $Na^+$ or $K^+$. The higher ionic strength suppressed and the lower enhanced the rate of superprecipitation respectively. 2. No effect of ouabain was found on the rate of superprecipitation. 3. Mitochondria depressed the rate of superpretipitation, and the depressed rate of superprecipitation by mitochondria was reversed by ouabain, and the degree of this reversal was almost identical in $Na^+$ and $K^+$ medium. 4. $Ca^{++}$ uptake of mitochondria was inhibited by ouabain in the presence of ATP and the degree of inhibition showed the dose-response manner in terms of concentration of ouabain. 5. In the absence of ATP, mitochondria took or the $Ca^{++}$ in initial period but released it later. Such uptake and release of $Ca^{++}$ was not influenced by ouabain. 6. It is suggested that intracellular calcium mobilization by ouabain through the action upon the mitochondria was due to inhibition on ATP-dependent $Ca^{++}$ uptake by this agent, not to the action upon so called binding.