Spatial and temporal Mg2+ signaling in single human tracheal gland cells.
AuthorsSébille S,Millot JM,Maizières M,Arnaud M,Delabroise AM,Jacquot J,Manfait M
JournalBiochemical and biophysical research communications
PubMed ID8886004
Are intracellular ionic concentrations accessible using fluorescent probes? The example of Mag-indo-1.
AuthorsMorelle B, Salmon JM, Vigo J, Viallet P
JournalCell Biol Toxicol
PubMed ID7697494
'The study of the physicochemical properties of Mag-indo-1, a fluorescent probe used for intracellular magnesium measurements, has shown that in a biological environment the deprotonated form of this probe is in simultaneous equilibrium with a protonated form, a protein and a magnesium-bound form. The complex emission fluorescence spectrum emitted by ... More
Regulation of intracellular free Mg2+ and contraction in single adult mammalian cardiac myocytes.
AuthorsSilverman HS, Di Lisa F, Hui RC, Miyata H, Sollott SJ, Hanford RG, Lakatta EG, Stern MD
JournalAm J Physiol
PubMed ID8304418
'Studies in isolated cardiac myocytes have increased our understanding of intracellular Ca2+ regulation. Because less is known about Mg2+ regulation, adult rat ventricular myocytes were loaded with the Mg(2+)-sensitive fluorescent probe mag-indo 1, and changes in intracellular Mg2+ concentration ([Mg2+]i) and cell length were examined under a variety of conditions. ... More
High cytoplasmic Ca2+ levels reached during Ca(2+)-induced Ca2+ release in single smooth muscle cell as reported by a low affinity Ca2+ indicator Mag-Indo-1.
AuthorsGanitkevich VYa Hirche H
JournalCell Calcium
PubMed ID8793179
'The low-affinity Ca2+ indicator Mag-Indo-1 was used to measure increments of ionised Ca2+ concentration in the cytoplasm of single smooth muscle cells isolated from guinea-pig urinary bladder. With 3.6 mM [Ca2+]o, depolarization steps to 0 mV were associated with a transient increase of fluorescence ratio (F410/F470) only when Ica triggered ... More
Mag-indo1 affinity for Ca(2+), compartmentalization and binding to proteins: the challenge of measuring Mg(2+) concentrations in living cells.
AuthorsPesco J, Salmon JM, Vigo J, Viallet P
JournalAnal Biochem
PubMed ID11237323
'A physicochemical study of the Mag-indo1 binding to Ca(2+) in solution showed that: (i) the characteristic fluorescence spectra of Ca(2+)-bound and Mg(2+)-bound Mag-indo1 are identical; (ii) two successive equilibria occur for increasing Ca(2+) concentrations; and (iii) the value of the dissociation constant of the first one, as determined by using ... More
Subcellular localization of glutamate-stimulated intracellular magnesium concentration changes in cultured rat forebrain neurons using confocal microscopy.
AuthorsCheng C, Reynolds IJ
JournalNeuroscience
PubMed ID10682704
'Glutamate can stimulate increases in intracellular magnesium concentration ([Mg2+]i) and induce neurotoxicity, both independent of Ca2+ changes. Although Mg2+ is essential within the cell, very little is known about how it is regulated, especially in neurons. Therefore we used the fluorescent indicator, magindo-1 and confocal microscopy to examine possible intracellular ... More
Role of Ca2+/K+ ion exchange in intracellular storage and release of Ca2+.
AuthorsNguyen T, Chin WC, Verdugo P
JournalNature
PubMed ID9804425
'Although fluctuations in cytosolic Ca2+ concentration have a crucial role in relaying intracellular messages in the cell, the dynamics of Ca2+ storage in and release from intracellular sequestering compartments remains poorly understood. The rapid release of stored Ca2+ requires large concentration gradients that had been thought to result from low-affinity ... More
Measurement of intracellular magnesium concentration in 3T3 fibroblasts with the fluorescent indicator Mag-indo-1.
AuthorsMorelle B, Salmon JM, Vigo J, Viallet P
JournalAnal Biochem
PubMed ID8053551
'Mag-indo-1, a fluorescent probe for measuring intracellular magnesium concentration, was used in 3T3 fibroblasts with microspectrofluorometry. The complex emission fluorescence spectrum emitted by a single living cell was analyzed with a computerized method, making it possible to evaluate the contribution of each species of Mag-indo-1 to the total fluorescence. The ... More
The effect of pH on rate constants, ion selectivity and thermodynamic properties of fluorescent calcium and magnesium indicators.
AuthorsLattanzio FA, Bartschat DK
JournalBiochem Biophys Res Commun
PubMed ID2043105
Fluorescent calcium indicators fluo-3, fura-2 and indo-1, and fluorescent magnesium indicators mag-fura-2 (FURAPTRA) and mag-indo-1 were evaluated for the effects of pH on their association and dissociation rates, ion selectivity and thermodynamic properties. Calcium indicator affinities for Ca and Mg were reduced and the discrimination between Ca and Mg decreased ... More
Cyclic Ca2+ changes in intracellular stores of gonadotropes during gonadotropin-releasing hormone-stimulated Ca2+ oscillations.
AuthorsTse FW, Tse A, Hille B
JournalProc Natl Acad Sci U S A
PubMed ID7937885
Gonadotropin-releasing hormone induces oscillatory release of Ca2+ from inositol trisphosphate-sensitive stores of gonadotropes. Simultaneously with electrophysiological measures of cytoplasmic [Ca2+], corresponding changes in [Ca2+] within intracellular stores were monitored with a fluorescent dye, mag-indo-1. Each cycle of oscillation released only 10% of the detectable stored Ca2+. Some Ca2+ was recovered ... More
Regulation of intracellular Mg2+ by superoxide in amnion cells.
AuthorsMasumoto N, Tasaka K, Mizuki J, Miyake A, Tanizawa O
JournalBiochem Biophys Res Commun
PubMed ID1310402
Changes of intracellular free Mg2+ concentration ([Mg2+]i) in human amnion cells induced by superoxide anion were determined using a highly Mg(2+)-sensitive fluorescent dye Mg(2+)-fura2 or Mg(2+)-indol. Superoxide anion, produced by addition of xanthine oxidase to hypoxanthine, induced decrease of [Mg2+]i. The decrease was significantly inhibited by an anion channel blocker, ... More
Extracellular Mg2+ inhibits both histamine-stimulated Ca(2+)-signaling and exocytosis in human tracheal secretory gland cells.
AuthorsSebille S, Pereira M, Millot JM, Jacquot J, Delabroise AM, Arnaud M, Manfait M
JournalBiochem Biophys Res Commun
PubMed ID9600077
The effects of extracellular Mg2+ concentration have been investigated on the histamine-stimulated exocytotic process of human tracheal secretory gland (HTG) cells. The exocytosis of secretory granules (SG) was observed concomitantly with dynamic changes of intracellular Ca2+ ([Ca2+]i) and Mg2+ concentrations ([Mg2+]i). The rate of SG exocytosis was appraised by the ... More
L-glutamate increases internal free calcium levels in synaptoneurosomes from immature rat brain via quisqualate receptors.
AuthorsBenavides J, Claustre Y, Scatton B
JournalJ Neurosci
PubMed ID2903912
Internal free calcium concentrations ([Ca2+]i) have been monitored in synaptoneurosomes from 8-d-old rat whole brain previously loaded with the calcium-sensitive fluorescent probe Fura 2. Under basal conditions, [Ca2+]i was around 200 nM, this concentration increasing only slowly during storage of the synaptoneurosomes at room temperature (40% increase 2 hr after ... More
Properties of tri- and tetracarboxylate Ca2+ indicators in frog skeletal muscle fibers.
AuthorsZhao M, Hollingworth S, Baylor SM
JournalBiophys J
PubMed ID8789107
Recently a number of lower-affinity fluorescent Ca2+ indicators have become available with principal absorbance bands at visible wavelengths. This article evaluates these indicators, as well as two shorter wavelength indicators, mag-fura-5 and mag-indo-1, for their suitability as rapid Ca2+ indicators in frog skeletal muscle fibers. With three lower-affinity tricarboxylate indicators ... More
Interaction of a protein, BSA, and a fluorescent probe, Mag-Indo-1, influence of EDTA and calcium on the equilibrium.
AuthorsRibou AC, Vigo J, Viallet P, Salmon JM
JournalBiophys Chem
PubMed ID10535100
Recent findings indicate that ion-chelator probes with tetracarboxylate structure bind proteins. It was suggested that these fluorescent probes are valuable tools to gain information on protein structure through the energy transfer from tryptophans to the bound probe. Here, the binding of the fluorescent probe Mag-Indo-1 to bovine serum albumin (BSA) ... More
Amino acid sequences and Ca2(+)-binding properties of two isoforms of barnacle troponin C.
AuthorsCollins JH, Theibert JL, Francois JM, Ashley CC, Potter JD
JournalBiochemistry
PubMed ID1988057
Much of our knowledge of the relationship between elevation of free sarcoplasmic [Ca2+] and skeletal muscle contraction has come from physiological studies on barnacle muscle fibers. Little is known, however, about the biochemical properties of the barnacle proteins responsible for Ca2+ regulation. In order to help rectify this unfortunate situation, ... More
Loss of cardiac magnesium in experimental heart failure prolongs and destabilizes repolarization in dogs.
AuthorsHaigney MC, Wei S, Kääb S, Griffiths E, Berger R, Tunin R, Kass D, Fisher WG, Silver B, Silverman H
JournalJ Am Coll Cardiol
PubMed ID9502656
OBJECTIVES: We sought to determine whether heart failure results in loss of cardiac magnesium sufficient to alter cellular electrophysiology. BACKGROUND: Free magnesium has numerous intracellular roles affecting metabolism, excitability and RNA synthesis. Total cardiac magnesium content is reduced in heart failure, but it is unclear whether magnesium loss is primary ... More