• Title, Summary, Keyword: ATP

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Simulation of ATP Metabolism in Cardiac Excitation - Contraction Coupling

  • Matsuoka, Satoshi;Sarai, Nobuaki;Jo, Hikari;Noma, Akinori
    • Proceedings of the Korean Biophysical Society Conference
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    • pp.19-19
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    • 2003
  • We have developed a cardiac cell model (Kyoto Model) for the sinoatrial node and ventricle, which is composed of a common set of kinetic equations of membrane ionic currents, Ca$\^$2+/dynamics of sarcoplasmic reticulum and contractile protein. To expand this model by including metabolic pathways, the intracellular ATP metabolism, which is pivotal in cardiac excitation - contraction coupling, was incorporated. ATP consumption by the sarcolemmal Na$\^$+/ pump and the Ca pump in the sarcoplasmic reticulum were calculated with stoichiometry of 3Na:2K:1ATP and 2Ca:1ATP, respectively. ATP consumption by contraction was estimated according to experimental data. Dependence of contraction on ATP and inorganic phosphate was modeled, based on data of skinned cardiac fiber. in production by mitochondrial oxidative phosphorylation was modified from Korzeniewski '||'&'||' Zoladz (2001), and creatine kinase and adenylate kinase reactions were incorporated. ATP dependence of ATP-sensitive K channel and L type Ca channel were also included.

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Total Microbial Biomass Measured by ATP in Three Marine Sedimentary Environments (아데노신 3인산(ATP; Adenosine-5′ triphosphate)을 이용한 심해저 및 연안퇴적토의 총 미생물 생체량 측정)

  • 현정호;김경홍;권개경;이정현;이홍금;김상진;김기현
    • Korean Journal of Microbiology
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    • v.38 no.2
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    • pp.119-126
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    • 2002
  • ATP concentrations far estimating total microbial biomass in the sediment were measured in three different marine sedimentary environments. ATP concentrations were highest in the surface sediment and decreased with increasing sediment depth and distance from the land. The results indicated that the benthic microbial biomass is primarily controlled by nutrient inputs from the overlying water column. Because of the longer residence time and adsorption to the sediment, the variations in organic carbon (OC) contents with sites and depths were not as distinct as that of ATP, and the correlation between OC and ATP was not significant in the coastal sediments. No significant correlation between OC and ATP in the coastal sediments also suggested that microbial biomass in the labile organic-enriched coastal sediment is suppressed by the grazing of higher trophic level such as meiofauna. Overall regional and vertical distribution of ATP indicated that h\`w can be a relevant tool for measuring total microbial biomass in various marine sedimentary environments.

Determination of Intracellular ATP of bacteria on the surface of Chicken (Bioluminescence방법에 의한 계육표면에 존재하는 세균수 측정)

  • Choi, Byung-Kyu;Kim, Jong-Bae;Shin, Heuyn-Kil;Lee, Seoung-Bae
    • Korean Journal of Food Science and Technology
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    • v.18 no.2
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    • pp.88-92
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    • 1986
  • Determination of bacterial adenosine triphosphate (ATP) based on luciferin-luciferase bioluminescene reaction was applied to the measurement of bacteria on the surface of chicken as an alternative rapid method. The light yield was proportional to the concentration of ATP giving a straight line within a range of $10^{-10}\;to\;10^{-6}M$. The bacteria isolated from the surface of chicken were identified as Escherichia coli, Hafnia alvei, Pseudomonas putida and Aeromonas hydrophila. When the ATP contents of each bacteria were determined by bioluminescence reaction and compared, there was no significant difference (r = 0.95). The Patterns of growth curves for E. coli look very similar, when the bacterial growth was monitored by ATP content and viable cell count. When bacterial ATP of each samples collected every 2 days during storage for 14 days at $4^{\circ}C$was determined and compared with viable cell count, it gave a good correlation (r = 0.95, n = 32).

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Application of ATP Bioluminescence Method for Measurement of Microbial Contamination in Raw Meat, Meat and Dairy Processing Line (식육 및 육가공 . 유가공 생산라인의 환경미생물오염도 측정을 위한 ATP 방법의 이용)

  • 강현미;엄양섭;안흥석;김천제;최경환;정충일
    • Journal of Food Hygiene and Safety
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    • v.15 no.3
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    • pp.252-255
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    • 2000
  • This study was conducted to investigate the application of ATP bioluminescence to measure the degree of microbial contamination from raw meat, meat processing and milk processing lines. Samples collected from slaughter house, meat and milk processing plants were tested for estimation of bacterial number by using ATP bioluminescence and conventional method. The former result was transffered to R-mATP value(log RLU/ml), and the latter transffered to CFU(log/ml). Correlation coefficient(r) between aerobic counts(CFU, log/ml) and R-mATP(log RLU/ml) value was 0.93(n=408). R-mATP of aerobic counts from beef, pork, chicken was 0.93(n=220), and that was 0.93(n=187) between meat processing and dairy processing plants. In addition, Correlation coefficient(r) between aerobic counts and R-mATP was 0.87(n=252) under 1$\times$10${^5}$/ml of bacterial count and 0.74(n=152) over 10${^5}$ respectively.

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Analysis of Tilting Train Installation and Installation Test for ATP(Automatic Train Protection) On-board Equipment (ATP 차상장치의 틸팅열차 설치 및 설치시험 분석)

  • Baek, Jong-Hyen
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.7
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    • pp.2534-2540
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    • 2010
  • In this paper we propose contents and results on installation and commissioning test for ATP on-board unit, which has propelled as one of the research projects, so called, "Reliability assessment and operation technology development for Korean-type tilting trains" in order to ensure the safety and operation efficiency of tilting trains. In KRRI, we have developed tilting trains for the speed-up of existing lines and for the passenger service improvement where the KTX is not available. And we also make progress the operation trial test at the speed of 10km with the use of ATS units, used in existing lines, for the purpose of the reliability assessment of the developed tilting trains. In MLTM, they have decided to accelerate the speed at more than 200km/h for the 7 existing lines including Jungang-line and Chungbuk-line where KTX has not operated. According to this decision, Train control system is to be changed from ATS to ATP. We should install an ATP on-board unit in tilting trains and verify the operational suitability. Therefore, we have installed and tested the same ATP on-board unit on tilting trains that used in the ATP construction project on Gyeongbu-line and Honam-line.

Apoptosis Induced by Adenosine 5'-triphosphate in Mouse Leukemic Cells (Mouse Leukemia 세포에서 Adenosine 5'-triphosphate에 의한 Apoptosis)

  • Joo, Nan-Young;Park, Kyu-Sang;Chung, Hae-Sook;Kong, In-Deok;Lee, Joong-Woo
    • The Korean Journal of Physiology and Pharmacology
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    • v.1 no.6
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    • pp.817-824
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    • 1997
  • Extracellular ATP elicits various biological responses and plays a significant role in physiological regulation. Recently, ATP-induced growth inhibitions were reported in some tumor cell lines, but these effects and mechanisms are not well hewn. This study was conducted to investigate ATP-induced growth inhibition in mouse $leukemic(P388D_1)$ cells. ATP inhibited cell growth in a dose-dependent manner as analyzed by MTS assay$(IC_{50}: 33.1\;{\mu}M)$. Nucleotides other than ATP, such as ADP$(37.5;{\mu}M)$ and AMP$(33.2;{\mu}M)$ had the same effects as ATP but adenosine$(57.8;{\mu}M)$ showed less effect than ATP. ATP attenuated the cells in $G_0/G_l\;and\;G_2/M$ phases but increased those in S phase in flow cytometric analysis. Hypodiploid cells$(A_0)$, the presumptive findings of apoptosis, were found among the ATP-treated cells. ATP induced DNA fragmentation into $180{\mu}200\;bps $as measured by electrophoresis. some apoptotic cells were stained by TUNEL method. ATP increased the intracellular free $Ca^{++}$concentration$([Ca^{++}]_i)$ and the increment of $([Ca^{++}]_i)$ was caused by influx from the extracellular space. These results suggest that extracellular ATP induces growth inhibition through apoptosis.

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Evidence for Adenosine Triphosphate (ATP) as an Excitatory Neurotransmitter in Guinea-Pig Gastric Antrum

  • Kang, Tong-Mook;Xu, Wenxie;Kim, Sung-Joon;Ahn, Seung-Cheol;Kim, Young-Chul;So, In-Suk;Park, Myoung-Kyu;Uhm, Dae-Yong;Kim, Ki-Whan
    • The Korean Journal of Physiology and Pharmacology
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    • v.3 no.2
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    • pp.165-174
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    • 1999
  • We explore the question of whether adenosine 5'-triphosphate (ATP) acts as an excitatory neurotransmitter in guinea-pig gastric smooth muscle. In an organ bath system, isometric force of the circular smooth muscle of guinea-pig gastric antrum was measured in the presence of atropine and guanethidine. Under electrical field stimulation (EFS) at high frequencies (>20 Hz), NO-mediated relaxation during EFS was followed by a strong contraction after the cessation of EFS (a 'rebound-contraction'). Exogenous ATP mimicked the rebound-contraction. A known $P_{2Y}-purinoceptor$ antagonist, reactive blue 2 (RB-2), blocked the rebound-contraction while selective desensitization of $P_{2Y}-purinoceptor$ with ${\alpha},{\beta}-MeATP$ did not affect it. ATP and 2-MeSATP induced smooth muscle contraction, which was effectively blocked by RB-2 and suramin, a nonselective $P_2-purinoceptor$ antagonist. Particularly, in the presence of RB-2, exogenous ATP and 2-MeSATP inhibited spontaneous phasic contractions, suggesting the existence of different populations of purinoceptors. Both the rebound-contraction and the agonist-induced contraction were not inhibited by indomethacin. The rank orders of agonists' potency were 2-MeSATP > ATP ${ge}$ UTP for contraction and ${\alpha},{\beta}-MeATP\;{\ge}\;{\beta},{\gamma}-MeATP$ for inhibition of the phasic contraction, that accord with the commonly accepted rank order of the classical $P_{2Y}-purinoceptor$ subtypes. Electrical activities of smooth muscles were only slightly influenced by ATP and 2-MeSATP, whereas ${\alpha},{\beta}-MeATP$ attenuated slow waves with membrane hyperpolarization. From the above results, it is suggested that ATP acts as an excitatory neurotransmitter, which mediates the rebound-contraction via $P_{2Y}-purinoceptor$ in guinea-pig gastric antrum.

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ATP Receptor/Channels: Their Contribution to Calcium Regulation and Modulation by Neurotransmitters

  • Nakazawa, Ken
    • Proceedings of the Korean Biophysical Society Conference
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    • pp.11-12
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    • 1997
  • A concept that extracellular ATP plays a role as a neurotransmitter is now widely accepted. ATP released from nerve terminals transmits both excitatory and inhibitory signals to postsynaptic neurons, muscle cells, and non-excitable cells. ATP-activated channels are effectors that convert the binding of ATP into the opening of ion channel pores in postsynaptic membrane.(omitted)

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Application of ATP Bioluminescence Assay for a Rapid Estimation of Microbial Levels in Mackerel(Scomber japonicus) (고등어 표피의 미생물 오염도 신속측정을 위한 ATP Bioluminescence assay)

  • Oh, Se-Wook;Jo, Jin-Ho;Lee, Nam-Hyouck
    • Korean Journal of Food Science and Technology
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    • v.31 no.5
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    • pp.1345-1348
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    • 1999
  • The utility of a bioluminescence adenosine triphosphate(ATP) assay method for estimating bacterial levels in mackerel(Scomber japonicus) was investigated. Mackerel was stored at $1^{\circ}C$ throughout 10 days and its RLU(relative light unit) and APC(aerobic plate count) was determined. The ATP bioluminescence assay was validated during the storage of 32 samples, resulting in an agreement between the ATP assay and standard plate count methods of over 90% credibility. Therefore, ATP bioluminescence assay was considered as a rapid and near real-time means in estimating the microbial load on mackerel skin.

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Effects of Exogenous ATP on Calcium Mobilization and Cell Proliferation in C6 Glioma Cell

  • Lee, Eun-Jung;Cha, Seok-Ho;Lee, Woon-Kyu;Lee, Kweon-Haeng;Lee, Sang-Bok
    • The Korean Journal of Physiology and Pharmacology
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    • v.2 no.4
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    • pp.419-425
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    • 1998
  • To clarify the effect of extracellular ATP in cultured C6 glioma cells, ATP-induced cytosolic free calcium ($[Ca^{2+}]_i$) mobilization and cell proliferation were investigated. ATP-induced $[Ca^{2+}]_i$ increased in a dose-dependent manner $(10^{-7}\;M{\sim}10^{-3}\;M)$. ATP-induced $[Ca^{2+}]_i$ increases were slightly slowed in extracellular calcium-free conditions especially in sustained phase. ATP-induced $[Ca^{2+}]_i$ increment was also inhibited by the pretreatment of U73122, a phospholipase C (PLC) inhibitor, in a time-dependent manner. Suramin, a putative $P_{2Y}$ receptor antagonist, dose-dependently weakened ATP-induced $[Ca^{2+}]_i$ mobilization. Significant increases in cell proliferation were observed at 2, 3, and 4 days after ATP was added. Stimulated cell proliferation was also observed with adenosine at days 2 and 3. This cell proliferation was significantly inhibited by the treatment with suramin. Ionomycin also stimulated cell proliferation in a concentration-dependent manner. In conclusion, we suggest that extracellular ATP stimulates C6 glioma cell proliferation via intracellular free calcium mobilization mediated by purinoceptor.

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