• 제목/요약/키워드: $H^+-influx$

검색결과 141건 처리시간 0.019초

Calcium수송기전에 미치는 Carbachol의 영향 (Calcium Movement in Carbachol-stimulated Cell-line)

  • 이종화
    • 대한약리학회지
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    • 제31권3호
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    • pp.355-363
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    • 1995
  • Calcium수송에 대한 기전을 추구하기위하여, carbachol을 사용하여 ml muscarinic receptor-transfected RBL-2H3 cell-line에서 다음과 같은 실험결과를 얻었기에 이에 보고한다. 1) Carbachol의 투여로 이들 cell-line에서 $Ca^{2+}$ influx가 농도에 따라 증가하였고, hexosaminidase 분비양도 의의있게 증가하였다. 2) Atropine 투여로 Carbachol의 상승작용이 의의있게 억제되었다. 3) 수종의 금속양이온을 투여하여 carbachol의 $Ca^{2+}$수송에 대한 영향을 관찰한 바, 이들 금속이온들은 $Ca^{2+}$의 influx를 의의있게 억제하였다. 4) PMA(20 nM) 투여로 carbachol의 hexosaminidase의 분비는 억제되지 못했지만 $Ca^{2+}$ influx는 억제되었다. 5) PTx $(0.2\;{\mu}g/ml)$ 투여로 carbachol의 hexosaminidase 분비가 의의있게 억제되었다. 위의 결과로 미루어 보아, 이 세포의 muscarinic receptor가 calcium channel을 통한 calcium수송에 매우 중요한 영향을 나타내는데, 이들 calcium ion channel은 적어도 두 종류가 존재하며, 하나는G-protein-dependent calcium channel에 의하며, 다른 하나는 G-protein-independent calcium channel에 대한 작용에 의한 것으로 생각된다. 또한 이 calcium channel들은 2가 또는 3가의 다른 금속 ion들에 의하여 calcium수송이 억제된다.

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Regulation of the Contraction Induced by Emptying of Intracellular $Ca^{2+}$ Stores in Cat Gastric Smooth Muscle

  • Baek, Hye-Jung;Sim, Sang-Soo;Rhie, Duck-Joo;Yoon, Shin-Hee;Hahn, Sang-June;Jo, Yang-Hyeok;Kim, Myung-Suk
    • The Korean Journal of Physiology and Pharmacology
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    • 제4권2호
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    • pp.113-120
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    • 2000
  • To investigate the mechanism of smooth muscle contraction induced by emptying of intracellular $Ca^{2+}$ stores, we measured isometric contraction and $^{45}Ca^{2+}$ influx. $CaCl_2$ increased $Ca^{2+}$ store emptying- induced contraction in dose-dependent manner, but phospholipase C activity was not affected by the $Ca^{2+}$ store emptying-induced contraction. The contraction was inhibited by voltage-dependent $Ca^{2+}$ channel antagonists dose dependently, but not by TMB-8 (intracellular $Ca^{2+}$ release blocker). Both PKC inhibitors (H-7 and staurosporine) and tyrosine kinase inhibitors (genistein and methyl 2,5-dihydroxycinnamic acid) significantly inhibited the contraction, but calmodulin antagonists (W-7 and trifluoperazine) had no inhibitory effect on the contraction. The combined inhibitory effects of protein kinase inhibitors, H-7 and genistein, together with verapamil were greater than that of each one alone. In $Ca^{2+}$ store-emptied condition, $^{45}Ca^{2+}$ influx was significantly inhibited by verapamil, H-7 or genistein but not by trifluoperazine. However combined inhibitory effects of protein kinase inhibitors, H-7 and genistein, together with verapamil were not observed. Therefore, this kinase pathway may modulate the sensitivity of contractile protein. These results suggest that contraction induced by emptying of intracellular $Ca^{2+}$ stores was mediated by influx of extracellular $Ca^{2+}$ through voltage-dependent $Ca^{2+}$ channel, also protein kinase C and/or tyrosine kinase pathway modulates the $Ca^{2+}$ sensitivity of contractile protein.

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Fractions of Chamaecyparis obtusa Display Antiallergic Effect in RBL2H3 Cells

  • Choi, In-Gyu;Kim, Kyung-Jong;Kim, Young-Mi;Park, Mi-Jin;Lee, Yun-Sil;Jeoung, Doo-Il
    • Journal of Microbiology and Biotechnology
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    • 제16권11호
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    • pp.1747-1752
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    • 2006
  • Allergic inflammation results from stimulation of ${\beta}$-hexosaminidase secretion, increased calcium influx, and activation of MAPK pathways. Some fractions of Chamaecyparis obtusa decreased secretion of ${\beta}$-hexosaminidase, calcium influx, ROS, and phosphorylation of ERK. These results suggest that Chamaecyparis obtusa would be valuable for development of allergy therapeutics.

Cloning of a Novel $Na^+$-Dependent L-Serine Specific Symporter Gene from Haemophilus influenzae Rd and Characteristics of the Transporter

  • Kim, Young-Mog;Rhee, In-Koo;Tsuchiya, Tomofusa
    • Journal of Microbiology and Biotechnology
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    • 제14권3호
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    • pp.520-524
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    • 2004
  • A protein that exhibited a high similarity to a major serine transporter of Escherichia coli, SdaC, was found in Haemophilus injluenzae Rd. Also, $Na^+$-stimulated serine transport activity was detected in the cells. The sdaC of H. injluenzae was cloned and the properties of the transporter were investigated. The activity of serine transport was stimulated by $Na^+$. Uptake of $Na^+$ elicited by L-serine influx into cells was also observed, which supports the idea that L-serine is transported by a mechanism of $Na^+$serine symport. No uptake of $H^+$ elicited by L-serine influx was detected. This result was not consistent with that obtained with the homologous protein, SdaC of E. coli, which uses $H^+$as a coupling cation. The serine transport via the SdaC of H. influenzae was not inhibited by other amino acids such as threonine or D-serine like the SdaC of E. coli. Thus, the SdaC of H. influenzae is a $Na^+$-dependent L-serine specific symporter and an unusual natural mutant. The $K_m$ and the $V_{max}$, value for the serine transport in the SdaC of H. influenzae were $7.6\mu$M and 22.9 nmol/min/mg protein, respectively.

C5a에 의해 자극된 호중구에서 세포내 칼슘동원에 대한 Protein Tyrosine Kinase의 조절작용 (Regulatory Action of Protein Tyrosine Kinase in Intracellular Calcium Mobilization in C5a-stimulated Neutrophils)

  • 최원태;한은숙;이정수
    • 대한약리학회지
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    • 제32권3호
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    • pp.417-424
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    • 1996
  • 본 연구는 C5a에 의해 자극된 호중구에서 세포내 칼슘유리와 세포외부로부터 칼슘유입에 있어 protein kinase C와 protein tyrosine kinase의 관여 여부를 조사하였다. Protein kinase C 억제제인 staurosporine과 H-7은 C5a에 의해 자극된 호중구에서 세포내 칼슘유리를 억제하였으나, 세포막을 교차한 칼슘유입이나 세포내 칼슘농도 증가에 영향을 나타내지 않았다. C5a에 의한 세포내 칼슘유리와 칼슘유입은 protein tyrosine kinase 억제제인 genistein과 methyl-2,5-dihydroxycinnamate에 의해서 억제 되었다. ADP에 의해 야기된 세포내 칼슘농도의 증가는 genistein과 methyl-2,5-dihydroxycinnamate에 의해서 억제되었으나 staurosporine과 H-7의 영향은 받지 않았다. Genistein과 methyl-2,5-dihydroxy-cinnamate는 thapsigargin을 처리한 호중구에서 칼슘유입을 감소시켰으나 이에 대한 staurosporine 과 H-7의 효과는 나타나지 않았다. 호중구를 phorbol 12-myristate 13-acetate로 전처치하였을때 세포내 칼슘증가에 미치는 C5a의 자극 효과는 감소하였다. 이상의 결과로 부터 protein tyrosine kinase는 C5a에 의해 활성화된 호중구에서 세포내 칼슘유리와 세포막을 교차한 칼슘유입의 조절에 관여할 것으로 추정된다.

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Characteristics of $Na^{+}$-dependent Serine Transport in Haemophilus Influenzae Rd

  • Kim, Young-Mog;Rhee, In-Koo;Park, Mi-Yeon;Chang, Dong-Suck;Tomofusa Tsuchiya
    • Journal of Microbiology
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    • 제41권2호
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    • pp.78-82
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    • 2003
  • We identified two proteins in Haemophilus influenzae Rd that exhibited high similarity to two major serine transporters of Escherichia coli (SstT and SdaC). Then, we investigated serine transport in H. influenzae Rd and detected $Na^{+}$-stimulated L-serine transport activity. The optimum NaCl concentration for this stimulation was about 20 mM. The uptake of $Na^{+}$ by H. influenzae Rd was found to be elicited by L-serine influx, which supports the idea that L-serine is transported by a mechanism of $Na^{+}$/serine symport. No uptake of $H^{+}$ elicited by L-serine influx was detected. $Na^{+}$/serine symport activity was not inhibited by other amino acids such as L-threonine or D-serine. Two distinct Km values were obtained from the kinetic analysis of serine transport. Thus, two serine transport pathways may exist in H. influenzae Rd, and it appears that both systems are stimulated by $Na^{+}$.

Activation of the Chemosensory Ion Channels TRPA1 and TRPV1 by Hydroalcohol Extract of Kalopanax pictus Leaves

  • Son, Hee Jin;Kim, Yiseul;Misaka, Takumi;Noh, Bong Soo;Rhyu, Mee-Ra
    • Biomolecules & Therapeutics
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    • 제20권6호
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    • pp.550-555
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    • 2012
  • TRPA1 and TRPV1 are members of the TRP superfamily of structurally related, nonselective cation channels. TRPA1 and TRPV1 are often co-expressed in sensory neurons and play an important role in somatosense such as cold, pain, and irritants. The first leaves of Kalopanax pictus Nakai (Araliaceae) have long been used as a culinary ingredient in Korea because of their unique chemesthetic flavor. In this study, we observed the intracellular $Ca^{2+}$ response to cultured cells expressing human TRPA1 (hTRPA1) and human TRPV1 (hTRPV1) by $Ca^{2+}$ imaging analysis to investigate the ability of the first leaves of K. pictus to activate the hTRPA1 and hTRPV1. An 80% ethanol extract of K. pictus (KPEx) increased intracellular $Ca^{2+}$ influx in a response time- and concentration-dependent manner via either hTRPA1 or hTRPV1. KPEx-induced response to hTRPA1 was markedly attenuated by ruthenium red, a general blocker of TRP channels, and HC-030031, a specific antagonist of TRPA1. In addition, the intracellular $Ca^{2+}$ influx attained with KPEx to hTRPV1 was mostly blocked by ruthenium red, and capsazepine, a specific antagonist of TRPV1. These results indicate that KPEx selectively activates both hTRPA1 and hTRPV1, which may provide evidence that the first leaves of K. pictus primarily activate TRPA1 and TRPV1 to induce their unique chemesthetic sense.

배양된 생쥐여포에서 $Ca^{++}$ Uptake에 대한 Gonadotropin의 영향 (Effect of Gonadotropin on $Ca^{++}$ Uptake in Follicle-Enclosed Mouse Oocytes Cultured in Vitro)

  • 배인하;강신해
    • Clinical and Experimental Reproductive Medicine
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    • 제18권2호
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    • pp.153-162
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    • 1991
  • The present study was undertaken to clarify the role of calcium ion as a factor for the maturation of follicle-enclosed mouse oocytes. Follicles were isolated with two sharp needles under a stereomicroscope from mouse(ICR) ovaries which were treated PMSG 5 IU 45 hours previously. Isolated follicles were cultured for 14-16 hours in an organ culture system at $37^{\circ}C$, 5% $CO_2$ in air and in a 100% humidified incubator by treatment of hCG, EDTA and $^{45}Ca^{++}$. Culture medium was Modified Hank's Balanced Salt Sol. (MHBS) and addition of hCG (human chorionic gonadotropin) was made into two doses level 0.4 IU and 0.8IU from the stock sol. and also $^{45}Ca^{++}$ was treated in the culture medium. To explain the role of calcium, calcium chelating agent EDTA was treated to the culture of the mouse follicle-enclosed oocytes. Two observations were made in the present study; nucleus phase and $^{45}Ca^{++}$ uptake into the oocyte. HCG induced oocyte maturation in the follicle about two folds as much as the control group, whereas there is no difference in oocyte maturation between 0.4 IU and 0.8 IU of hCG. Optimum level of hCG seems to be 0.4 IU/ml in the mouse follicle culture. HCG stimulated $^{45}Ca^{++}$ uptake into the oocyte of the follicles by two folds. $^{45}Ca^{++}$ uptake in the control group is about 2.5 folds in comparison of the EDTA(1.71mM) treated group. However, calcium uptake in the EDTA treated groups tends to increase depending on the decrease of EDTA concentration. These observations suggest that firstly, hCG stimulates maturation of the oocyte of the follicle, secondly, $Ca^{++}$ influx is induced by hCG and thirdly, $Ca^{++}$ influx by the treatment of EDTA decreases as a dosage-dependent process. This $Ca^{++}$ uptake may take place by the changes of permeability which was induced by hCG treatment. That is, $Ca^{++}$ influx may trigger the resumption of oocyte maturation. It is further necessary in the future study how this $Ca^{++}$ uptake is induced by hCG and increases permeability of the follicle and oocyte.

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무흡광색소 식물의 감광수용체 개발 연구(II) - 표고버섯의 광감응성 mitochondrial ATPase의 유기물 및 금속이온 유입 효과 - (Studies on the Development of Photoreceptor in the Nonchromatophore Organisms (II) - Effects of organic compound and metal ion influx of Light-Induced Mitochondrial ATPase in the Lentinus edodes(Berk.) Sing -)

  • 민태진;조석우;김영순;김재웅;민태익
    • 한국균학회지
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    • 제15권4호
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    • pp.224-230
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    • 1987
  • 표고버섯의 미토콘드리아는 설탕밀도 선형기울기 원심분리법으로 정제하여, 광감응성 mitochondrial ATPase의 유기물 효과, 광증감제 효과 및 파장 변화에 따른 $K^+$ 이온의 유입 효과를 실험하였다. 1. 이 효소는 10m mol dithiothreitol 및 0.1m mol quinacrine에 의하여 각각 139% 및 128%의 활성도를 증가시켰다. 2. $100\;{\mu}g$의 oligomycin과 1m mol phlorizin은 이 효소의 활성을 각각 48% 및 45% 억제시켰다. 3. 광증감제인 0.1m mol phenazine methosulfate는 이 효소의 활성도를 36% 촉진시켰다. 4. $K^+$ 이온 유입 효과의 최적 파장은 690nm였고, 이때의 최적 pH 및 최적 온도는 각각 7.2 및 $55^{\circ}C$였다.

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