The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
Chemical Compound Review

Furaptra     2-[6- (bis(carboxymethyl)amino)- 5...

Synonyms: Mag-fura-2, AG-D-44862, ACMC-20mozs, CTK0H8842, AC1L3XE4, ...
Welcome! If you are familiar with the subject of this article, you can contribute to this open access knowledge base by deleting incorrect information, restructuring or completely rewriting any text. Read more.

Disease relevance of Furaptra

  • By fluorescence spectroscopy with furaptra-loaded cells, the free intracellular Mg2+ concentration within the intact neuroblastoma cells was found to increase from 0 [1].
  • The intracellular magnesium and calcium concentrations in cultured dorsal root ganglion neurons were measured using a fluorescent Mg2+ indicator, Mag-Fura-2 and a Ca2+ indicator, Fura-2, respectively [2].
  • Fluorescence measurements of free [Mg2+] by use of mag-fura 2 in Salmonella enterica [3].
  • To test the hypothesis that abnormal platelet Ca2+ handling in essential hypertension results from cellular Mg2+ deficiency, cytosolic free Mg2+ concentration ([Mg2+]i) and Ca2+ metabolism were studied in mag-fura 2 and fura 2-loaded platelets from 30 essential hypertensive patients and 30 sex- and age-matched normotensive controls [4].

High impact information on Furaptra

  • METHODS: We evaluated the effects of DCA on Ca2+ signaling in BHK-21 fibroblasts using fura-2 and mag-fura-2 to measure cytoplasmic and intraluminal internal stores [Ca2+], respectively [5].
  • Making use of the fluorescent dye mag-fura 2 to measure free Mg(2+) concentrations continuously, we describe here a high capacity, rapid Mg(2+) influx system in isolated yeast mitochondria, driven by the mitochondrial membrane potential Deltapsi and inhibited by cobalt(III)hexaammine [6].
  • Ca homeostasis in thapsigargin-sensitive internal Ca stores of single permeabilized BHK-21 fibroblasts was examined using digital image processing of compartmentalized mag-fura-2 (a low-affinity Ca indicator) [7].
  • Free [Ca] within organelles of permeabilized BHK-21 cells was measured using ratio imaging of compartmentalized mag-fura-2 [8].
  • In experiments using cells loaded with mag-fura-2 to report endoplasmic reticulum Ca(2+), Msp reduced Ca(2+) efflux from endoplasmic reticulum stores when ATP was used as an agonist [9].

Biological context of Furaptra

  • In fibers containing less than 0.5 mM furaptra and stimulated by a single action potential, the calibrated peak value of delta[Ca2+] averaged 5.1 (+/- 0.3, SEM) microM [10].
  • These binding kinetics do not explain the difference in the size of the [Ca2+]i transients reported by fura-2 and furaptra [11].
  • The continuation of exocytosis was correlated with a persistent increase in [Ca2+]i in the synaptic terminal, as indicated by the activation of a Ca2+-dependent conductance and measurements of [Ca2+]i using the fluorescent indicator furaptra [12].
  • As detected with Mag-Fura-2, a brief 50ms light flash activated rapid Ca(2+) depletion of SER, followed by an effective refilling within 1min of dark adaptation after the light flash [13].
  • Furaptra is present at high concentrations (up to 500 microM) in the matrix when introduced by hydrolysis of the acetoxymethyl ester [14].

Anatomical context of Furaptra

  • To investigate the mechanism responsible for this quantal release phenomenon, [Ca2+] changes inside intracellular stores in isolated single smooth muscle cells were monitored with mag-fura 2 [15].
  • Free Ca2+ was measured in intracellular stores of individual mouse pancreatic beta-cells using dual-wavelength microfluorometry and the low-affinity Ca2+ indicator furaptra [16].
  • Controlled permeabilization of the plasma membrane with 4 micromol/l digitonin revealed that 22% of the furaptra was trapped in intracellular nonnuclear compartments [16].
  • Porcine aortic endothelial cells were extensively coupled, as assessed by gap junctional transfer of Lucifer yellow and the fluorescent calcium indicators fluo-3 and furaptra, but were not permeable to rhodamine B isothiocyanate-dextran 10S [17].
  • Myoplasmic calcium transients in intact frog skeletal muscle fibers monitored with the fluorescent indicator furaptra [10].

Associations of Furaptra with other chemical compounds


Gene context of Furaptra

  • Ionic selectivity of low-affinity ratiometric calcium indicators: mag-Fura-2, Fura-2FF and BTC [23].
  • The peak calcium transient studied with mag-fura-2 (400 microM) was 6.3 +/- 0.4 microM and 4.2 +/- 0.3 microM for young and old muscle fibers, respectively [24].
  • In cells loaded with the Mg(2+)-sensitive fluorescent indicator, Mag-fura-2, intracellular Mg2+ concentration ([Mg2+]i) increased after exposure to EGF after a 5-min lag; a similar lag was routinely observed before the stimulation of 28Mg2+ uptake by EGF [25].
  • Because the total Mg content and cell volume remained constant during this time, the difference between the amount of Mg2+ liberated (2.7 mM) and the 0.9 mM increase in cytosolic Mg2+ activity measured fluorometrically with mag-fura-2 indicates a sizable Mg2+ buffering [26].

Analytical, diagnostic and therapeutic context of Furaptra

  • Fluorometry with the dye, mag-fura-2, was used to characterize intracellular Mg2+ concentration ([Mg2+]i) in single cTAL cells [27].
  • The regulation of the intracellular free Mg2+ concentration ([Mg2+]i) was monitored in rat sublingual mucous acini using dual wavelength microfluorometry of the Mg(2+)-sensitive dye mag-fura-2 [28].
  • Recordings using the low-affinity dye mag-fura-2 and a Cs+-based intracellular solution revealed a similar pattern of hot spots in response to depolarisation, ruling out measurement artefacts or possible effects of inhomogeneous dye distribution in the generation of hot spots [29].
  • Extracellular perfusion of muscle fibers with high Mg2+ concentration solution or low Na+ concentration solution did not cause any detectable changes in the [Mg2+]-related furaptra fluorescence within 4 min [30].
  • 3. In the current study we used the low-affinity Ca2+ indicator mag-fura-2 to reexamine the spatiotemporal distribution pattern of Ca2+ after axotomy and to map the free intracellular Mg2+ concentration gradients [31].


  1. Competition between Li+ and Mg2+ in neuroblastoma SH-SY5Y cells: a fluorescence and 31P NMR study. Amari, L., Layden, B., Nikolakopoulos, J., Rong, Q., Mota de Freitas, D., Baltazar, G., Castro, M.M., Geraldes, C.F. Biophys. J. (1999) [Pubmed]
  2. Intracellular Mg2+ surge follows Ca2+ increase during depolarization in cultured neurons. Gotoh, H., Kajikawa, M., Kato, H., Suto, K. Brain Res. (1999) [Pubmed]
  3. Fluorescence measurements of free [Mg2+] by use of mag-fura 2 in Salmonella enterica. Froschauer, E.M., Kolisek, M., Dieterich, F., Schweigel, M., Schweyen, R.J. FEMS Microbiol. Lett. (2004) [Pubmed]
  4. Abnormal platelet Ca2+ handling accompanied by increased cytosolic free Mg2+ in essential hypertension. Hiraga, H., Oshima, T., Yoshimura, M., Matsuura, H., Kajiyama, G. Am. J. Physiol. (1998) [Pubmed]
  5. Deoxycholic acid activates protein kinase C and phospholipase C via increased Ca2+ entry at plasma membrane. Lau, B.W., Colella, M., Ruder, W.C., Ranieri, M., Curci, S., Hofer, A.M. Gastroenterology (2005) [Pubmed]
  6. Mrs2p is an essential component of the major electrophoretic Mg2+ influx system in mitochondria. Kolisek, M., Zsurka, G., Samaj, J., Weghuber, J., Schweyen, R.J., Schweigel, M. EMBO J. (2003) [Pubmed]
  7. ATP regulates calcium leak from agonist-sensitive internal calcium stores. Hofer, A.M., Curci, S., Machen, T.E., Schulz, I. FASEB J. (1996) [Pubmed]
  8. Spatial distribution and quantitation of free luminal [Ca] within the InsP3-sensitive internal store of individual BHK-21 cells: ion dependence of InsP3-induced Ca release and reloading. Hofer, A.M., Schlue, W.R., Curci, S., Machen, T.E. FASEB J. (1995) [Pubmed]
  9. A spirochete surface protein uncouples store-operated calcium channels in fibroblasts: a novel cytotoxic mechanism. Wang, Q., Ko, K.S., Kapus, A., McCulloch, C.A., Ellen, R.P. J. Biol. Chem. (2001) [Pubmed]
  10. Myoplasmic calcium transients in intact frog skeletal muscle fibers monitored with the fluorescent indicator furaptra. Konishi, M., Hollingworth, S., Harkins, A.B., Baylor, S.M. J. Gen. Physiol. (1991) [Pubmed]
  11. Ca2+ transients in cardiac myocytes measured with high and low affinity Ca2+ indicators. Berlin, J.R., Konishi, M. Biophys. J. (1993) [Pubmed]
  12. The kinetics of exocytosis and endocytosis in the synaptic terminal of goldfish retinal bipolar cells. Neves, G., Lagnado, L. J. Physiol. (Lond.) (1999) [Pubmed]
  13. InsP(3)-induced Ca(2+) release in permeabilized invertebrate photoreceptors: a link between phototransduction and Ca(2+) stores. Ukhanov, K., Mills, S.J., Potter, B.V., Walz, B. Cell Calcium (2001) [Pubmed]
  14. On the use of fluorescent probes to estimate free Mg2+ in the matrix of heart mitochondria. Jung, D.W., Chapman, C.J., Baysal, K., Pfeiffer, D.R., Brierley, G.P. Arch. Biochem. Biophys. (1996) [Pubmed]
  15. The quantal nature of calcium release to caffeine in single smooth muscle cells results from activation of the sarcoplasmic reticulum Ca(2+)-ATPase. Steenbergen, J.M., Fay, F.S. J. Biol. Chem. (1996) [Pubmed]
  16. In situ characterization of nonmitochondrial Ca2+ stores in individual pancreatic beta-cells. Tengholm, A., Hagman, C., Gylfe, E., Hellman, B. Diabetes (1998) [Pubmed]
  17. Porcine aortic endothelial gap junctions: identification and permeation by caged InsP3. Carter, T.D., Chen, X.Y., Carlile, G., Kalapothakis, E., Ogden, D., Evans, W.H. J. Cell. Sci. (1996) [Pubmed]
  18. Extracellular Mg2+ regulates intracellular Mg2+ and its subcellular compartmentation in fission yeast, Schizosaccharomyces pombe. Zhang, A., Cheng, T.P., Wu, X.Y., Altura, B.T., Altura, B.M. Cell. Mol. Life Sci. (1997) [Pubmed]
  19. Measurement of matrix free Mg2+ concentration in rat heart mitochondria by using entrapped fluorescent probes. Rutter, G.A., Osbaldeston, N.J., McCormack, J.G., Denton, R.M. Biochem. J. (1990) [Pubmed]
  20. Intracellular and extracellular concentrations of Na+ modulate Mg2+ transport in rat ventricular myocytes. Tashiro, M., Tursun, P., Konishi, M. Biophys. J. (2005) [Pubmed]
  21. Allosteric regulation by cytoplasmic Ca2+ and IP3 of the gating of IP3 receptors in permeabilized guinea-pig vascular smooth muscle cells. Hirose, K., Kadowaki, S., Iino, M. J. Physiol. (Lond.) (1998) [Pubmed]
  22. Simultaneous measurements of Ca2+ in the intracellular stores and the cytosol of hepatocytes during hormone-induced Ca2+ oscillations. Chatton, J.Y., Liu, H., Stucki, J.W. FEBS Lett. (1995) [Pubmed]
  23. Ionic selectivity of low-affinity ratiometric calcium indicators: mag-Fura-2, Fura-2FF and BTC. Hyrc, K.L., Bownik, J.M., Goldberg, M.P. Cell Calcium (2000) [Pubmed]
  24. Excitation-calcium release uncoupling in aged single human skeletal muscle fibers. Delbono, O., O'Rourke, K.S., Ettinger, W.H. J. Membr. Biol. (1995) [Pubmed]
  25. Effect of epidermal growth factor on magnesium homeostasis in BC3H1 myocytes. Grubbs, R.D. Am. J. Physiol. (1991) [Pubmed]
  26. Mg2+ buffering in cultured chick ventricular myocytes: quantitation and modulation by Ca2+. Koss, K.L., Putnam, R.W., Grubbs, R.D. Am. J. Physiol. (1993) [Pubmed]
  27. Intracellular Mg2+ and magnesium depletion in isolated renal thick ascending limb cells. Dai, L.J., Quamme, G.A. J. Clin. Invest. (1991) [Pubmed]
  28. Secretagogue-induced mobilization of an intracellular Mg2+ pool in rat sublingual mucous acini. Zhang, G.H., Melvin, J.E. J. Biol. Chem. (1992) [Pubmed]
  29. Action potential-evoked Ca2+ signals and calcium channels in axons of developing rat cerebellar interneurones. Forti, L., Pouzat, C., Llano, I. J. Physiol. (Lond.) (2000) [Pubmed]
  30. Fluorescence signals from the Mg2+/Ca2+ indicator furaptra in frog skeletal muscle fibers. Konishi, M., Suda, N., Kurihara, S. Biophys. J. (1993) [Pubmed]
  31. Axotomy induces a transient and localized elevation of the free intracellular calcium concentration to the millimolar range. Ziv, N.E., Spira, M.E. J. Neurophysiol. (1995) [Pubmed]
WikiGenes - Universities