The engagement of integrin α7 in E63 skeletal muscle cells by laminin or anti-α7 antibodies triggered transient elevations in the intracellular free Ca(2+) concentration that resulted from both inositol triphosphate-evoked Ca(2+) release from intracellular stores and extracellular Ca(2+) influx through voltage-gated, L-type Ca(2+) channels. The extracellular domain of integrin α7 ... More
Cellular alterations produced by the experimental increase in intracellular calcium and the nature of protective effects from pretreatment with nimodipine.
The immortalized septal cell line, SN56 B5 G4, generated by the fusion of mouse septal area cells and neuroblastoma cells, was used to determine if nimodipine, an antagonist of voltage sensitive calcium 'L' channels, might act in a neuroprotective fashion when intracellular calcium levels were raised by incubation in ouabain ... More
Morphine-3-glucuronide's neuro-excitatory effects are mediated via indirect activation of N-methyl-D-aspartic acid receptors: mechanistic studies in embryonic cultured hippocampal neurones.
AuthorsHemstapat K,Monteith GR,Smith D,Smith MT
JournalAnesthesia and analgesia
PubMed ID12873944
Indirect evidence indicates that morphine-3-glucuronide (M3G) may contribute significantly to the neuro-excitatory side effects (myoclonus and allodynia) of large-dose systemic morphine. To gain insight into the mechanism underlying M3G's excitatory behaviors, we used fluo-3 fluorescence digital imaging techniques to assess the acute effects of M3G (5-500 microM) on the cytosolic ... More
Developmental regulation of neuroligand-induced responses in cultured oligodendroglia.
Using whole-cell patch-clamp techniques, we show that oligosphere-derived oligodendrocyte progenitor cells (OP) display GABA-, glutamate-, 5-HT-, glycine- and acetylcholine-gated inward currents. When OP differentiate into oligodendrocytes (ODC), the amplitude of peak currents elicited by saturating concentrations of these transmitters decreases except for 5-HT. Intracellular Ca2+ concentration changes induced by microperfusion ... More
Direct detection of uncaged glutamate and the laser photostimulation of cultured rat cortex.
AuthorsTorimitsu K, Niwa O
JournalNeuroreport
PubMed ID9559923
The photostimulation of nerve cells using a caged compound is very useful because it is non-invasive and non-destructive compared with standard electrophysiological techniques. There are no methods, however, for continuously measuring the photo-uncaged 'free' compound concentration at high temporal and spatial resolutions which can detect how much uncaged compound has ... More
Flow cytometric functional analysis of multidrug resistance by Fluo-3: a comparison with rhodamine-123.
AuthorsKoizumi S, Konishi M, Ichihara T, Wada H, Matsukawa H, Goi K, Mizutani S
JournalEur J Cancer
PubMed ID7488425
Using four cell lines including drug-sensitive K562/Parent cells, P-glycoprotein (Pgp)-mediated multidrug resistant (MDR) K562/VCR, K562/ADR and revertant K562/ADR-R cells, two fluorescent agents, Fluo-3 and rhodamine-123 (Rh-123), were compared as indicators in a functional assay of MDR. Cells were incubated with 4 microM Fluo-3 or 1 microM Rh-123 for 45 min ... More
Calcium signaling.
AuthorsClapham DE
JournalCell
PubMed ID7834745
Analysis of calcium binding to alpha-lactalbumin using a fluorescent calcium indicator.
AuthorsEberhard M, Erne P
JournalEur J Biochem
PubMed ID1765086
A sensitive and rapid assay of Ca2+ binding to proteins was developed, based on the competition of Ca2+ binding to the protein of interest and fluo-3, a fluorescent Ca2+ indicator. Ca2+ binding to fluo-3 and bovine alpha-lactalbumin was analyzed at ten different pH values and a range of Na+ and ... More
Selected contribution: effect of volatile anesthetics on cADP-ribose-induced Ca(2+) release system.
AuthorsChini EN
JournalJ Appl Physiol
PubMed ID11408471
Volatile anesthetics have multiple actions on intracellular Ca(2+) homeostasis, including activation of the ryanodine channel (RyR) and sensitization of this channel to agonists such as caffeine and ryanodine. Recently it has been described that the nucleotide cADP-ribose (cADPR) is the endogenous regulator of the RyR in many mammalian cells, and ... More
Intracellular Ca2+ signals evoked by stimulation of nicotinic acetylcholine receptors in SH-SY5Y cells: contribution of voltage-operated Ca2+ channels and Ca2+ stores.
AuthorsDajas-Bailador FA, Mogg AJ, Wonnacott S
JournalJ Neurochem
PubMed ID12065669
Neuronal nicotinic acetylcholine receptors (nAChR) can regulate several neuronal processes through Ca2+-dependent mechanisms. The versatility of nAChR-mediated responses presumably reflects the spatial and temporal characteristics of local changes in intracellular Ca2+ arising from a variety of sources. The aim of this study was to analyse the components of nicotine-evoked Ca2+ ... More
Simultaneous recording of receptor current and intraciliary Ca2+ concentration in salamander olfactory receptor cells.
AuthorsReisert J, Matthews HR
JournalJ Physiol
PubMed ID11559763
1. The suction pipette technique was combined with laser spot fluorescence microscopy to record simultaneously odour-induced current responses and intraciliary Ca2+ concentration from isolated salamander olfactory receptor cells loaded with the fluorescent Ca2+ indicator fluo-3. 2. When exposed for 1 s to increasing odour concentrations both the suction pipette current ... More
Conformational and biochemical differences in the TCR.CD3 complex of CD8(+) versus CD4(+) mature lymphocytes revealed in the absence of CD3gamma.
AuthorsZapata DA, Pacheco-Castro A, Torres PS, Ramiro AR, San José E, Alarcón B, Alibaud L, Rubin B, Toribio ML, Regueiro JR
JournalJ Biol Chem
PubMed ID10574994
'Mature CD4(+) and CD8(+) T lymphocytes are believed to build and express essentially identical surface alphabeta T-cell receptor-CD3 (TCR.CD3) complexes. However, TCR.CD3 expression has been shown to be more impaired in CD8(+) cells than in CD4(+) cells when CD3gamma is absent in humans or mice. We have addressed this paradox ... More
Amino acid residues critical for endoplasmic reticulum export and trafficking of platelet-activating factor receptor.
AuthorsHirota N, Yasuda D, Hashidate T, Yamamoto T, Yamaguchi S, Nagamune T, Nagase T, Shimizu T, Nakamura M,
JournalJ Biol Chem
PubMed ID20007715
'Several residues are conserved in the transmembrane domains (TMs) of G-protein coupled receptors. Here we demonstrate that a conserved proline, Pro(247), in TM6 of platelet-activating factor receptor (PAFR) is required for endoplasmic reticulum (ER) export and trafficking after agonist-induced internalization. Alanine-substituted mutants of the conserved residues of PAFRs, including P247A, ... More
Histamine regulates cytokine production in maturing dendritic cells, resulting in altered T cell polarization.
AuthorsMazzoni A, Young HA, Spitzer JH, Visintin A, Segal DM
JournalJ Clin Invest
PubMed ID11748270
'Atopic diseases such as allergy and asthma are characterized by increases in Th2 cells and serum IgE antibodies. The binding of allergens to IgE on mast cells triggers the release of several mediators, of which histamine is the most prevalent. Here we show that histamine, together with a maturation signal, ... More
The yeast prion Ure2p native-like assemblies are toxic to mammalian cells regardless of their aggregation state.
AuthorsPieri L, Bucciantini M, Nosi D, Formigli L, Savistchenko J, Melki R, Stefani M
JournalJ Biol Chem
PubMed ID16571726
'The yeast prion Ure2p assembles in vitro into oligomers and fibrils retaining the alpha-helix content and binding properties of the soluble protein. Here we show that the different forms of Ure2p native-like assemblies (dimers, oligomers, and fibrils) are similarly toxic to murine H-END cells when added to the culture medium. ... More
TRPC1 associates with BK(Ca) channel to form a signal complex in vascular smooth muscle cells.
AuthorsKwan HY, Shen B, Ma X, Kwok YC, Huang Y, Man YB, Yu S, Yao X,
JournalCirc Res
PubMed ID19168436
'TRPC1 (transient receptor potential canonical 1) is a Ca(2+)-permeable cation channel involved in diverse physiological function. TRPC1 may associate with other proteins to form a signaling complex, which is crucial for channel function. In the present study, we investigated the interaction between TRPC1 and large conductance Ca(2+)-sensitive K(+) channel (BK(Ca)). ... More
Inhibition of protein palmitoylation, raft localization, and T cell signaling by 2-bromopalmitate and polyunsaturated fatty acids.
AuthorsWebb Y, Hermida-Matsumoto L, Resh MD
JournalJ Biol Chem
PubMed ID10617614
'The ability of the Src family kinases Fyn and Lck to participate in signaling through the T cell receptor is critically dependent on their dual fatty acylation with myristate and palmitate. Here we identify a palmitate analog, 2-bromopalmitate, that effectively blocks Fyn fatty acylation in general and palmitoylation in particular. ... More
Triad formation: organization and function of the sarcoplasmic reticulum calcium release channel and triadin in normal and dysgenic muscle in vitro.
AuthorsFlucher BE, Andrews SB, Fleischer S, Marks AR, Caswell A, Powell JA
JournalJ Cell Biol
PubMed ID8245124
'Excitation-contraction (E-C) coupling is thought to involve close interactions between the calcium release channel (ryanodine receptor; RyR) of the sarcoplasmic reticulum (SR) and the dihydropyridine receptor (DHPR) alpha 1 subunit in the T-tubule membrane. Triadin, a 95-kD protein isolated from heavy SR, binds both the RyR and DHPR and may ... More
Involvement of nuclear factor of activated T cells activation in UV response. Evidence from cell culture and transgenic mice.
AuthorsHuang C, Mattjus P, Ma WY, Rincon M, Chen NY, Brown RE, Dong Z
JournalJ Biol Chem
PubMed ID10734048
'Mammalian cells respond to UV radiation by signaling cascades leading to activation of transcription factors, such as activated protein 1, NFkappaB, and p53, a process known as the "UV response." Nuclear factor of activated T cells (NFAT) was first identified as an inducible nuclear factor in immune response and subsequently ... More
Inositol 1,3,4,5-tetrakisphosphate is essential for T lymphocyte development.
AuthorsPouillon V, Hascakova-Bartova R, Pajak B, Adam E, Bex F, Dewaste V, Van Lint C, Leo O, Erneux C, Schurmans S
JournalNat Immunol
PubMed ID14517551
'Inositol 1,4,5-trisphosphate (Ins(1,4,5)P(3)) is phosphorylated by Ins(1,4,5)P(3) 3-kinase, generating inositol 1,3,4,5-tetrakisphosphate (Ins(1,3,4,5)P(4)). The physiological function of Ins(1,3,4,5)P(4) is still unclear, but it has been reported to be a potential modulator of calcium mobilization. Disruption of the gene encoding the ubiquitously expressed Ins(1,4,5)P(3) 3-kinase isoform B (Itpkb) in mice caused a ... More
The platelet cytoskeleton regulates the affinity of the integrin alpha(IIb)beta(3) for fibrinogen.
AuthorsBennett JS, Zigmond S, Vilaire G, Cunningham ME, Bednar B
JournalJ Biol Chem
PubMed ID10464255
'Agonist-generated inside-out signals enable the platelet integrin alpha(IIb)beta(3) to bind soluble ligands such as fibrinogen. We found that inhibiting actin polymerization in unstimulated platelets with cytochalasin D or latrunculin A mimics the effects of platelet agonists by inducing fibrinogen binding to alpha(IIb)beta(3). By contrast, stabilizing actin filaments with jasplakinolide prevented ... More
Real time fluorescence imaging of PLC gamma translocation and its interaction with the epidermal growth factor receptor.
AuthorsMatsuda M, Paterson HF, Rodriguez R, Fensome AC, Ellis MV, Swann K, Katan M
JournalJ Cell Biol
PubMed ID11331309
'The translocation of fluorescently tagged PLC gamma and requirements for this process in cells stimulated with EGF were analyzed using real time fluorescence microscopy applied for the first time to monitor growth factor receptor--effector interactions. The translocation of PLC gamma to the plasma membrane required the functional Src homology 2 ... More
Regulation of alphaIIb beta3 function in human B lymphocytes.
AuthorsQi W, Loh E, Vilaire G, Bennett JS
JournalJ Biol Chem
PubMed ID9614143
'We studied the function of the platelet integrin alphaIIb beta3 using a B lymphocyte model in which alphaIIb beta3 can be induced to interact with fibrinogen using phorbol myristate acetate (PMA). To determine whether a G protein-coupled receptor could also activate alphaIIb beta3 in lymphocytes, we coexpressed the human formyl ... More
Exercise training attenuates coronary smooth muscle phenotypic modulation and nuclear Ca2+ signaling.
AuthorsWamhoff BR, Bowles DK, Dietz NJ, Hu Q, Sturek M
JournalAm J Physiol Heart Circ Physiol
PubMed ID12388302
'Physical inactivity is an independent risk factor for coronary heart disease, yet the mechanism(s) of exercise-related cardioprotection remains unknown. We tested the hypothesis that coronary smooth muscle after exercise training would have decreased mitogen-induced phenotypic modulation and enhanced regulation of nuclear Ca(2+). Yucatan swine were endurance exercise trained (EX) on ... More
IL-4 enhances keratinocyte expression of CXCR3 agonistic chemokines.
AuthorsAlbanesi C, Scarponi C, Sebastiani S, Cavani A, Federici M, De Pità O, Puddu P, Girolomoni G
JournalJ Immunol
PubMed ID10903743
'IFN-induced protein of 10 kDa (IP-10), monokine induced by IFN-gamma (Mig), and IFN-inducible T-cell alpha-chemoattractant (I-TAC) belong to the non-glutamate-leucine-arginine motif CXC chemokine family and act solely through the CXCR3 receptor for potent attraction of T lymphocytes. In this study, we evaluated the capacity of the T cell-derived cytokines IL-4, ... More
Activated human T lymphocytes express a functional C3a receptor.
AuthorsWerfel T, Kirchhoff K, Wittmann M, Begemann G, Kapp A, Heidenreich F, Götze O, Zwirner J
JournalJ Immunol
PubMed ID11086104
'The C3a molecule is an anaphylatoxin of the C system with a wide spectrum of proinflammatory effects predominantly on cells of myeloid origin. In this study we investigated the expression of the high affinity receptor for C3a (C3aR) in human T lymphocytes using receptor-specific mAb. C3aR expression was detected in ... More
Vav1 and Ly-GDI two regulators of Rho GTPases, function cooperatively as signal transducers in T cell antigen receptor-induced pathways.
AuthorsGroysman M, Hornstein I, Alcover A, Katzav S
JournalJ Biol Chem
PubMed ID12386169
'The Rho family GTPases are pivotal for T cell signaling; however, the regulation of these proteins is not fully known. One well studied regulator of Rho GTPases is Vav1; a hematopoietic cell-specific guanine nucleotide exchange factor critical for signaling in T cells, including stimulation of the nuclear factor of activated ... More
Purinergic junctional transmission and propagation of calcium waves in spinal cord astrocyte networks.
AuthorsBennett MR, Buljan V, Farnell L, Gibson WG
JournalBiophys J
PubMed ID16905605
'Micro-photolithographic methods have been employed to form discrete patterns of spinal cord astrocytes that allow quantitative measurements of Ca(2+) wave propagation. Astrocytes were confined to lanes 20-100 microm wide and Ca(2+) waves propagated from a point of mechanical stimulation or of application of adenosine triphosphate; all Ca(2+) wave propagation was ... More
Plasma membrane repair is mediated by Ca(2+)-regulated exocytosis of lysosomes.
AuthorsReddy A, Caler EV, Andrews NW
JournalCell
PubMed ID11511344
'Plasma membrane wounds are repaired by a mechanism involving Ca(2+)-regulated exocytosis. Elevation in intracellular [Ca(2+)] triggers fusion of lysosomes with the plasma membrane, a process regulated by the lysosomal synaptotagmin isoform Syt VII. Here, we show that Ca(2+)-regulated exocytosis of lysosomes is required for the repair of plasma membrane disruptions. ... More
Novel subcellular and molecular tools to study Ca(2+) transport mechanisms during the elusive moulting stages of crustaceans: flow cytometry and polyclonal antibodies.
AuthorsWheatly M, Zhang Z, Weil J, Rogers J, Stiner L
JournalJ Exp Biol
PubMed ID11171419
'Our understanding of calcium homeostasis during the crustacean moulting cycle derives from research on intermoult animals that has been extrapolated to other stages. In terms of transepithelial Ca(2+) flux, the more interesting stages are those surrounding ecdysis since crustaceans experience a sizeable negative calcium balance in immediate premoult and a ... More
Vasopressin-induced cytoplasmic and nuclear calcium signaling in cultured cortical astrocytes.
AuthorsZhao L, Brinton RD
JournalBrain Res
PubMed ID12088846
'We sought to determine whether vasopressin V(1a) receptor (V(1a)R) mRNA detected in cortical astrocytes [Brain Res. Mol. Brain Res. 45 (1997) 138] was translated into functional receptors by investigating the effector calcium signaling cascade associated with the vasopressin V(1a) receptor subtype. Analysis of intracellular calcium dynamics using the calcium-sensitive dye ... More
High density distribution of endoplasmic reticulum proteins and mitochondria at specialized Ca2+ release sites in oligodendrocyte processes.
AuthorsSimpson PB, Mehotra S, Lange GD, Russell JT
JournalJ Biol Chem
PubMed ID9278423
'In oligodendrocyte processes, methacholine-evoked Ca2+ waves propagate via regions of specialized Ca2+ release kinetics (wave amplification sites) at which the amplitude and rate of rise of local Ca2+ signals are markedly higher than in surrounding areas (Simpson, P. B., and Russell, J. T. (1996) J. Biol. Chem. 271, 33493-33501). In ... More
Lead and calcium produce rod photoreceptor cell apoptosis by opening the mitochondrial permeability transition pore.
AuthorsHe L, Poblenz AT, Medrano CJ, Fox DA
JournalJ Biol Chem
PubMed ID10766853
'Calcium overload is suggested to play a fundamental role in the process of rod apoptosis in chemical-induced and inherited retinal degenerations. However, this hypothesis has not been tested directly. We developed an in vitro model utilizing isolated rat retinas to determine the mechanisms underlying Ca(2+)- and/or Pb(2+)-induced retinal degeneration. Confocal ... More
Regulation of cytosolic free calcium concentration by intrasynaptic mitochondria.
AuthorsMartínez-Serrano A, Satrústegui J
JournalMol Biol Cell
PubMed ID1550964
'By the use of digitonin permeabilized presynaptic nerve terminals (synaptosomes), we have found that intrasynaptic mitochondria, when studied "in situ," i.e., surrounded by their cytosolic environment, are able to buffer calcium in a range of calcium concentrations close to those usually present in the cytosol of resting synaptosomes. Adenine nucleotides ... More
CD18/ICAM-1-dependent oxidative NF-kappaB activation leading to nitric oxide production in rat Kupffer cells cocultured with syngeneic hepatoma cells.
AuthorsKurose I, Saito H, Miura S, Ebinuma H, Higuchi H, Watanabe N, Zeki S, Nakamura T, Takaishi M, Ishii H
JournalJ Clin Invest
PubMed ID9062344
'Previous studies have indicated that nitric oxide (NO) released from Kupffer cells modulates biological viability of cocultured hepatoma cells. This study was designed to evaluate the mechanisms by which Kupffer cells synthesize and release NO in reponse to cocultured hepatoma cells. Kupffer cells isolated from male Wistar rats were cocultured ... More
Evidence that the substance P-induced enhancement of pacemaking in lymphatics of the guinea-pig mesentery occurs through endothelial release of thromboxane A2.
AuthorsRayner SE, Van Helden DF
JournalBr J Pharmacol
PubMed ID9283691
'1. In vitro studies were performed to examine the mechanisms underlying substance P-induced enhancement of constriction rate in guinea-pig mesenteric lymphatic vessels. 2. Substance P caused an endothelium-dependent increase in lymphatic constriction frequency which was first significant at a concentration of 1 nM (115 +/- 3% of control, n = ... More
Detection of a trigger zone of bradykinin-induced fast calcium waves in PC12 neurites.
AuthorsReber BF, Schindelholz B
JournalPflugers Arch
PubMed ID8772141
'Bradykinin and caffeine were used as two different agonists to study inositol 1,4,5-trisphosphate (IP3)-sensitive and caffeine/ryanodine-sensitive intracellular Ca2+ release in the outgrowing neurites of nerve-growth-factor (NGF)-treated rat phaeochromocytoma cells (PC12). Changes in neuritic intracellular free Ca2+ ([Ca2+]i) in single cells were measured after loading with a 1:1 mixture of the ... More
Acetylcholine and potassium elicit different patterns of exocytosis in chromaffin cells when the intracellular calcium handling is disturbed.
AuthorsCuchillo-Ibáñez I, Olivares R, Aldea M, Villarroya M, Arroyo G, Fuentealba J, García AG, Albillos A
JournalPflugers Arch
PubMed ID11976925
'During fast superfusion of bovine chromaffin cells with normal Krebs-HEPES solution containing 2 mM Ca2+, pulses of 100 microM ACh or 100 mM K+ of increasing duration (1-5 s) caused similar exocytosis of about 3-4 microC catecholamine. Depletion of endoplasmic reticulum (ER) Ca2+ by pretreatment with 1 microM thapsigargin, 10 ... More
Images of Ca2+ flux in astrocytes: evidence for spatially distinct sites of Ca2+ release and uptake.
AuthorsLaskey AD, Roth BJ, Simpson PB, Russell JT
JournalCell Calcium
PubMed ID9924634
'In this study, we have developed a mathematical method to derive the Ca2+ fluxes underlying agonist-evoked Ca2+ waves in cultured rat cortical astrocytes. Astrocytes were stimulated with norepinephrine (100 nM) to evoke Ca2+ waves, which were recorded by measuring Fluo-3 fluorescence changes with high spatial and temporal resolution. Normalized fluorescence ... More
Presynaptic calcium signals and transmitter release are modulated by calcium-activated potassium channels.
AuthorsRobitaille R, Charlton MP
JournalJ Neurosci
PubMed ID1370323
'The regulation of synaptic transmission by Ca(2+)-activated potassium (gKca) channels was investigated at the frog neuromuscular junction (nmj). Charybdotoxin (CTX), a blocker of certain types of gKca channels, induced a twofold increase of transmitter release. Similar results were obtained with purified natural toxin, synthetic toxin, and recombinant toxin. Apamin, a ... More
Dynamic imaging of functional nerve terminals and Schwann cells in presynaptic 'nerve plates' isolated from the skate electric organ
AuthorsDowdall M, Green A, Richardson C
JournalJ Exp Biol
PubMed ID9317554
'The cholinergic innervation and its glial support were isolated in a functional state from the electric organ of the skate (Raja species) using a combined enzymatic and mechanical dissociation technique. Examination using light and electron microscopy showed that this ''nerve plate'' is a disc-shaped structure several hundred micrometres in diameter ... More
Fast Ca2+ signals at mouse inner hair cell synapse: a role for Ca2+-induced Ca2+ release.
AuthorsKennedy HJ, Meech RW
JournalJ Physiol
PubMed ID11850498
'Inner hair cells of the mammalian cochlea translate acoustic stimuli into ''phase-locked'' nerve impulses with frequencies of up to at least 1 kHz. Little is known about the intracellular Ca2+ signal that links transduction to the release of neurotransmitter at the afferent synapse. Here, we use confocal microscopy to provide ... More
Localization of the 12.6-kDa FK506-binding protein (FKBP12.6) binding site to the NH2-terminal domain of the cardiac Ca2+ release channel (ryanodine receptor).
AuthorsMasumiya H, Wang R, Zhang J, Xiao B, Chen SR
JournalJ Biol Chem
PubMed ID12446682
'The 12.6-kDa FK506-binding protein (FKBP12.6) interacts with the cardiac ryanodine receptor (RyR2) and modulates its channel function. However, the molecular basis of FKBP12.6-RyR2 interaction is poorly understood. To investigate the significance of the isoleucine-proline (residues 2427-2428) dipeptide epitope, which is thought to form an essential part of the FKBP12.6 binding ... More
Calcium elevation in sheep cumulus-oocyte complexes after luteinising hormone stimulation.
AuthorsMattioli M, Gioia L, Barboni B
JournalMol Reprod Dev
PubMed ID9621313
'We investigated Ca2+ levels in intact cumulus-oocyte complexes (COCs) on exposure to peak levels of luteinising hormone (LH). Specific preparations were used where cumulus corona cells were loaded with a membrane-permeant Ca(2+)-sensitive dye (FLUO-3AM), whereas the oocyte was injected directly with the nonpermeant form of the dye (FLUO-3). After exposure ... More
Trachynilysin mediates SNARE-dependent release of catecholamines from chromaffin cells via external and stored Ca2+.
AuthorsMeunier FA, Mattei C, Chameau P, Lawrence G, Colasante C, Kreger AS, Dolly JO, Molgó J
JournalJ Cell Sci
PubMed ID10704363
'Trachynilysin, a 159 kDa dimeric protein purified from stonefish (Synanceia trachynis) venom, dramatically increases spontaneous quantal transmitter release at the frog neuromuscular junction, depleting small clear synaptic vesicles, whilst not affecting large dense core vesicles. The basis of this insensitivity of large dense core vesicles exocytosis was examined using a ... More
Ca2+ sparks in embryonic mouse skeletal muscle selectively deficient in dihydropyridine receptor alpha1S or beta1a subunits.
AuthorsConklin MW, Powers P, Gregg RG, Coronado R
JournalBiophys J
PubMed ID9929471
'Ca2+ sparks are miniature Ca2+ release events from the sarcoplasmic reticulum of muscle cells. We examined the kinetics of Ca2+ sparks in excitation-contraction uncoupled myotubes from mouse embryos lacking the beta1 subunit and mdg embryos lacking the alpha1S subunit of the dihydropyridine receptor. Ca2+ sparks occurred spontaneously without a preferential ... More
N-oleoyldopamine, a novel endogenous capsaicin-like lipid that produces hyperalgesia.
AuthorsChu CJ, Huang SM, De Petrocellis L, Bisogno T, Ewing SA, Miller JD, Zipkin RE, Daddario N, Appendino G, Di Marzo V, Walker JM
JournalJ Biol Chem
PubMed ID12569099
'N-Arachidonoyldopamine (NADA) was recently identified as an endogenous ligand for the vanilloid type 1 receptor (VR1). Further analysis of the bovine striatal extract from which NADA was isolated indicated the existence of substances corresponding in molecular mass to N-oleoyldopamine (OLDA), N-palmitoyldopamine (PALDA), and N-stearoyldopamine (STEARDA). Quadrupole time-of-flight mass spectrometric analysis ... More
Frequency dependence of Ca2+ release from the sarcoplasmic reticulum in human ventricular myocytes from end-stage heart failure.
AuthorsSipido KR, Stankovicova T, Flameng W, Vanhaecke J, Verdonck F
JournalCardiovasc Res
PubMed ID9614502
'OBJECTIVES: Human cardiac muscle from failing heart shows a decrease in active tension development and a rise in diastolic tension at stimulation frequencies above 50-60 beats/min due to both systolic and diastolic dysfunction. We have investigated underlying changes in cellular [Ca2+]i regulation. METHODS: Single ventricular myocytes were isolated enzymatically from ... More
Nonlinear propagation of spherical calcium waves in rat cardiac myocytes.
AuthorsWussling MH, Salz H
JournalBiophys J
PubMed ID8785274
'Spontaneous calcium waves in enzymatically isolated rat cardiac myocytes were investigated by confocal laser scanning microscopy (CLSM) using the fluorescent Ca2+-indicator fluo-3 AM. As recently shown, a spreading wave of enhanced cytosolic calcium appears, most probably during Ca2+ overload, and is initiated by an elementary event called a "calcium spark." ... More
Human anti-CD38 autoantibodies raise intracellular calcium and stimulate insulin release in human pancreatic islets.
AuthorsAntonelli A, Baj G, Marchetti P, Fallahi P, Surico N, Pupilli C, Malavasi F, Ferrannini E
JournalDiabetes
PubMed ID11334442
'CD38 is involved in transmembrane signaling in many cell types; anti-CD38 autoantibodies have been described in diabetic patients. We tested whether human anti-CD38 antibodies possess signaling properties by measuring their ability to raise intracellular calcium ([Ca2+]i) using the fluo-3-acetoxymethyl ester method in a human-derived T-cell line (Jurkat T-cells, expressing high ... More
A simplified method for Ca2+ flux measurement on isolated human B cells that uses flow cytometry.
AuthorsGergely L, Cook L, Agnello V
JournalClin Diagn Lab Immunol
PubMed ID9008284
'A method for Ca2+ flux measurement on isolated human peripheral B cells that uses flow cytometry is described. B cells were isolated by anti-CD19 magnetic bead sorting, and Ca2+ flux was measured with the fluo-3 reagent on a standard single-laser flow cytometer. The response of B-cell stimulation by anti-immunoglobulin B ... More
Synaptic-type acetylcholine receptors raise intracellular calcium levels in neurons by two mechanisms.
AuthorsRathouz MM, Berg DK
JournalJ Neurosci
PubMed ID7965089
'Nicotinic acetylcholine receptors (AChRs) located in the postsynaptic membrane on neurons are responsible for mediating fast, excitatory synaptic transmission. If synaptic AChRs are also highly permeable to calcium as reported recently for several kinds of neuronal AChRs, the synaptic receptors could regulate calcium-dependent events in the neurons in concert with ... More
Different triggers for calcium oscillations in mouse eggs involve a ryanodine-sensitive calcium store.
AuthorsSwann K
JournalBiochem J
PubMed ID1417794
'Relative intracellular free Ca2+ concentrations ([Ca2+]i) were monitored in mature unfertilized mouse eggs by measuring fluorescence of intracellular fluo3. A number of different agents were found to cause sustained repetitive transient [Ca2+]i oscillations. These were microinjection of a cytosolic sperm factor, sustained injection of Ins-(1,4,5)P1, or extracellular addition of the ... More
Elevation of intracellular free calcium levels in HEp-2 cells infected with enteropathogenic Escherichia coli.
AuthorsBaldwin TJ, Ward W, Aitken A, Knutton S, Williams PH
JournalInfect Immun
PubMed ID2019431
'Enteropathogenic Escherichia coli (EPEC) are a class of diarrheagenic organisms that induce a characteristic attaching and effacing lesion in enterocytes and various cultured cell lines. Infection of cultured HEp-2 cells by EPEC isolates 2036-80 (serotype O119) and E2348-69 (serotype O127) resulted in significant elevation of intracellular free calcium levels, determined ... More
Fatty acyl-CoA-acyl-CoA-binding protein complexes activate the Ca2+ release channel of skeletal muscle sarcoplasmic reticulum.
AuthorsFulceri R, Knudsen J, Giunti R, Volpe P, Nori A, Benedetti A
JournalBiochem J
PubMed ID9230123
'We previously reported that fatty acyl-CoA esters activate ryanodine receptor/Ca2+ release channels in a terminal cisternae fraction from rabbit skeletal muscle [Fulceri, Nori, Gamberucci, Volpe, Giunti and Benedetti (1994) Cell Calcium 15, 109-116]. Skeletal muscle cytosol contains a high-affinity fatty acyl-CoA-binding protein (ACBP) [Knudsen, Hojrup, Hansen, H.O., Hansen, H.F. and ... More
Nuclear and cytosolic calcium are regulated independently.
'Nuclear calcium (Ca(2+)) regulates a number of important cellular processes, including gene transcription, growth, and apoptosis. However, it is unclear whether Ca(2+) signaling is regulated differently in the nucleus and cytosol. To investigate this possibility, we examined subcellular mechanisms of Ca(2+) release in the HepG2 liver cell line. The type ... More
Coordination between Ca2+ release and subsequent re-uptake in the sarcoplasmic reticulum.
AuthorsSaiki Y, Ikemoto N
JournalBiochemistry
PubMed ID10074365
'We here report the results of our recent effort to produce, in the isolated sarcoplasmic reticulum (SR), a biphasic Ca2+ release and Ca2+ re-uptake transient and to resolve the kinetic relationship between Ca2+ release and re-uptake of the released Ca2+. Ca2+ release from the SR was induced by polylysine (the ... More
Kinetics of calcium release by immunoaffinity-purified inositol 1,4,5-trisphosphate receptor in reconstituted lipid vesicles.
AuthorsHirota J, Michikawa T, Miyawaki A, Furuichi T, Okura I, Mikoshiba K
JournalJ Biol Chem
PubMed ID7642567
'The kinetics of inositol 1,4,5-trisphosphate (IP3)-induced Ca2+ release of the immunoaffinity-purified IP3 receptor (IP3R), reconstituted into lipid vesicles, was investigated using the fluorescent Ca2+ indicator fluo-3. IP3R was purified from mouse cerebellar microsomal fraction by using an immunoaffinity column conjugated with an anti-IP3R type 1 (IP3R1) antibody. The immunoblotting analysis ... More
Hydrolysis of Ca2+-sensitive fluorescent probes by perfused rat heart.
AuthorsScaduto RC, Grotyohann LW
JournalAm J Physiol Heart Circ Physiol
PubMed ID14561682
'Rat hearts were loaded with the fluorescent calcium indicators fura 2, indo 1, rhod 2, or fluo 3 to determine cytosolic calcium levels in the perfused rat heart. With fura 2, however, basal tissue fluorescence increased above anticipated levels, suggesting accumulation of intermediates of fura 2-AM deesterification. To examine this ... More
Hypoxia and cyanide induce depolarization and catecholamine release in dispersed guinea-pig chromaffin cells.
AuthorsInoue M, Fujishiro N, Imanaga I
JournalJ Physiol
PubMed ID9508841
'1. The perforated patch method and amperometry were used to determine whether the adrenal medullary cell itself is capable of sensing hypoxia and, if so, how such sensation is transduced to secretion of catecholamines (CA). 2. Exposure to hypoxia, cyanide (CN), or muscarine facilitated CA secretion from dissociated chromaffin cells. ... More
Thimerosal potentiates Ca2+ release mediated by both the inositol 1,4,5-trisphosphate and the ryanodine receptors in sea urchin eggs. Implications for mechanistic studies on Ca2+ signaling.
AuthorsTanaka Y, Tashjian AH
JournalJ Biol Chem
PubMed ID8157654
'Two intracellular Ca2+ release pathways are modulated by Ca2+ itself, namely Ca(2+)-induced Ca2+ release (classical CICR), and Ca(2+)-sensitized inositol 1,4,5-trisphosphate (InsP3)-induced Ca2+ release (CSIICR). Both of these pathways are thought to be important in generating cytosolic Ca2+ oscillations. Caffeine and the sulfhydryl reagent thimerosal (TMS) are frequently used as selective ... More
Improved four-color flow cytometry method using fluo-3 and triple immunofluorescence for analysis of intracellular calcium ion ([Ca2+]i) fluxes among mouse lymph node B- and T-lymphocyte subsets.
AuthorsGreimers R, Trebak M, Moutschen M, Jacobs N, Boniver J
JournalCytometry
PubMed ID8974866
'A visible-light, dual-laser, flow cytometric method was developed for the simultaneous analysis of intracellular ionized calcium concentration ([Ca2+]i) and three cell-surface markers (CD4, CD8, and Thy-1.2 antigens) by using the calcium probe fluo-3 and using R-phycoerythrin (PE), peridinin chlorophyll-alpha protein (PerCP), and allophycocyanin (APC) conjugated monoclonal antibodies (MoAbs). This improved ... More
The role of calcium and phosphorylation of cytosolic phospholipase A2 in regulating arachidonic acid release in macrophages.
AuthorsQiu ZH, Gijón MA, de Carvalho MS, Spencer DM, Leslie CC
JournalJ Biol Chem
PubMed ID9525925
'Arachidonic acid release is induced in macrophages with diverse agonists including calcium ionophores, phorbol myristate acetate (PMA), okadaic acid, and the phagocytic particle, zymosan, and correlates with activation of cytosolic phospholipase A2 (cPLA2). The role of calcium and phosphorylation of cPLA2 in regulating arachidonic acid release was investigated. Zymosan induced ... More
Transmural heterogeneity of calcium activity and mechanical function in the canine left ventricle.
AuthorsCordeiro JM, Greene L, Heilmann C, Antzelevitch D, Antzelevitch C
JournalAm J Physiol Heart Circ Physiol
PubMed ID14670817
'Although electrical heterogeneity within the ventricular myocardium has been the focus of numerous studies, little attention has been directed to the mechanical correlates. This study examines unloaded cell shortening, Ca(2+) transients, and inward L-type Ca(2+) current (I(Ca,L)) characteristics of epicardial, endocardial, and midmyocardial cells isolated from the canine left ventricle. ... More
Localisation, function and composition of primary Ca(2+) spark discharge region in isolated smooth muscle cells from guinea-pig mesenteric arteries.
AuthorsPucovský V, Bolton TB
JournalCell Calcium
PubMed ID16297446
'Smooth muscle cells (SMCs) contain numerous calcium release domains, grouped into regions discharging as a single unit. Laser scanning confocal microscopy, voltage clamp and immunocytochemistry of single SMCs from small mesenteric arteries of guinea-pig were used to study the localisation, function and macromolecular composition of such calcium discharge regions (CDRs). ... More
Differential regulation of skeletal muscle L-type Ca2+ current and excitation-contraction coupling by the dihydropyridine receptor beta subunit.
AuthorsBeurg M, Sukhareva M, Ahern CA, Conklin MW, Perez-Reyes E, Powers PA, Gregg RG, Coronado R
JournalBiophys J
PubMed ID10096875
'The dihydropyridine receptor (DHPR) of skeletal muscle functions as a Ca2+ channel and is required for excitation-contraction (EC) coupling. Here we show that the DHPR beta subunit is involved in the regulation of these two functions. Experiments were performed in skeletal mouse myotubes selectively lacking a functional DHPR beta subunit. ... More
Effects of angiotensin II on intracellular calcium and contracture in metabolically inhibited cardiomyocytes.
AuthorsBoston DR, Koyama T, Rodriguez-Larrain J, Zou A, Su Z, Barry WH
JournalJ Pharmacol Exp Ther
PubMed ID9580618
'Angiotensin II (A-II) is known to potentiate ischemic dysfunction during ischemia, but the mechanisms involved are not completely established. We examined the effects of A-II on intracellular calcium concentration ([Ca++]i) and cell contracture caused by metabolic inhibition in isolated adult rabbit ventricular myocytes. [Ca++]i was assessed by flow cytometry, using ... More
Developmental regulation of the hypothalamic metabotropic glutamate receptor mGluR1.
Authorsvan den Pol AN, Kogelman L, Ghosh P, Liljelund P, Blackstone C
JournalJ Neurosci
PubMed ID8207490
'The expression of the metabotropic glutamate receptor mGluR1 was studied with Northern and Western blot analysis, with immunocytochemistry, and with Ca2+ digital imaging in the developing rat hypothalamus. mGluR1 is coupled to a G protein and activation by glutamate and related agonists leads to intracellular phosphotidylinositol hydrolysis and Ca2+ mobilization. ... More
Nitric oxide-dependent mitochondrial biogenesis generates Ca2+ signaling profile of lupus T cells.
AuthorsNagy G, Barcza M, Gonchoroff N, Phillips PE, Perl A
JournalJ Immunol
PubMed ID15356113
'Abnormal T cell activation and cell death underlie the pathology of systemic lupus erythematosus. Although mitochondrial hyperpolarization (MHP) represents an early and reversible checkpoint of T cell activation and apoptosis, lupus T cells exhibit persistent MHP. NO has recently been recognized as a key signal of mitochondrial biogenesis and mediator ... More
Stimulation of calcium influx and calcium cascade by cyclic AMP in cultured carrot cells.
AuthorsKurosaki F, Nishi A
JournalArch Biochem Biophys
PubMed ID8385897
'Treatment of cultured carrot (Daucus carota L.) cells with activators of adenylate cyclase, forskolin, and cholera toxin induced the biosynthesis of an antifungal isocoumarin, 6-methoxymellein, in the cells. Addition of dibutyryl cyclic AMP to carrot cell culture also stimulated the accumulation of the compound. The cyclic AMP-evoked 6-methoxymellein production was ... More
AM-loading of fluorescent Ca2+ indicators into intact single fibers of frog muscle.
AuthorsZhao M, Hollingworth S, Baylor SM
JournalBiophys J
PubMed ID9168048
'The AM loading of a number of different fluorescent Ca2+ indicators was compared in intact single fibers of frog muscle. Among the 13 indicators studied, loading rates (the average increase in the fiber concentration of indicator per first 60 min of loading) varied approximately 100-fold, from approximately 3 microM/h to ... More
Characterization of a plasma membrane calcium oscillator in rat pituitary somatotrophs.
AuthorsTomic M, Koshimizu T, Yuan D, Andric SA, Zivadinovic D, Stojilkovic SS
JournalJ Biol Chem
PubMed ID10585449
'In excitable cells, oscillations in intracellular free calcium concentrations ([Ca(2+)](i)) can arise from action-potential-driven Ca(2+) influx, and such signals can have either a localized or global form, depending on the coupling of voltage-gated Ca(2+) influx to intracellular Ca(2+) release pathway. Here we show that rat pituitary somatotrophs generate spontaneous [Ca(2+)](i) ... More
The immunomodulatory beta-galactoside-specific lectin from mistletoe: partial sequence analysis, cell and tissue binding, and impact on intracellular biosignalling of monocytic leukemia cells.
AuthorsGabius HJ, Walzel H, Joshi SS, Kruip J, Kojima S, Gerke V, Kratzin H, Gabius S
JournalAnticancer Res
PubMed ID1622124
'Nanogram quantities of the beta-galactoside-specific lectin from mistletoe (ML-I) that is composed of two different types of subunits exhibit immunomodulatory potency and enhance cytokine secretion in vitro and in vivo. Partial sequence analysis of the carbohydrate-binding B chain revealed a ragged N-terminus and overall homologies to the B subunit of ... More
Role of Na+/Ca2+ exchange in [Ca2+]i clearance in rat culture Purkinje neurons requires reevaluation.
AuthorsRojas H, Ramos M, Mijares A, DiPolo R
JournalJpn J Physiol
PubMed ID14606965
'Previous studies have shown that in contrast to other neuronal cells, Na(+)/Ca(2+) exchange contributes little to Ca(i)(2+) homeostasis in rat cerebellar Purkinje neurons under intracellular perfused conditions and at room temperature [Fierro et al.: J Physiol (Lond) 510: 499-512, 1998]. The purpose of this study was to clarify the role ... More
Factors shaping the confocal image of the calcium spark in cardiac muscle cells.
AuthorsPratusevich VR, Balke CW
JournalBiophys J
PubMed ID8968567
'The interpretation of confocal line-scan images of local [Ca2+]i transients (such as Ca2+ sparks in cardiac muscle) is complicated by uncertainties in the position of the origin of the Ca2+ spark (relative to the scan line) and by the dynamics of Ca(2+)-dye interactions. An investigation of the effects of these ... More
Calcitonin gene-related peptide decreases expression of HLA-DR and CD86 by human dendritic cells and dampens dendritic cell-driven T cell-proliferative responses via the type I calcitonin gene-related peptide receptor.
AuthorsCarucci JA, Ignatius R, Wei Y, Cypess AM, Schaer DA, Pope M, Steinman RM, Mojsov S
JournalJ Immunol
PubMed ID10725702
'These studies were performed to establish whether functional receptors for calcitonin gene-related peptide (CGRP) are present on human dendritic cells (DCs) and to investigate potential immunomodulatory effects of CGRP on DCs other than Langerhans cells. Reverse transcriptase-PCR revealed expression of mRNA for a type 1 CGRP receptor by mature and ... More
Role of cAMP and calcium influx in endothelin-1-induced ANP release in rat cardiomyocytes.
AuthorsRebsamen MC, Church DJ, Morabito D, Vallotton MB, Lang U
JournalAm J Physiol
PubMed ID9374678
'The mechanism of endothelin-1 (ET-1)-induced atrial natriuretic peptide (ANP) release was studied in neonatal rat ventricular cardiomyocytes. These cells expressed a single high-affinity class of ETA receptor (dissociation constant = 54 +/- 18 pM, n = 3), but no ETB receptors. Incubation of cardiomyocytes with ET-1 led to concentration-dependent ANP ... More
Imaging caffeine-induced Ca2+ transients in individual fast-twitch and slow-twitch rat skeletal muscle fibers.
AuthorsPagala MK, Taylor SR
JournalAm J Physiol
PubMed ID9530093
'Fast-twitch and slow-twitch rat skeletal muscles produce dissimilar contractures with caffeine. We used digital imaging microscopy to monitor Ca2+ (with fluo 3-acetoxymethyl ester) and sarcomere motion in intact, unrestrained rat muscle fibers to study this difference. Changes in Ca2+ in individual fibers were markedly different from average responses of a ... More
HgCl2-induced interleukin-4 gene expression in T cells involves a protein kinase C-dependent calcium influx through L-type calcium channels.
AuthorsBadou A, Savignac M, Moreau M, Leclerc C, Pasquier R, Druet P, Pelletier L
JournalJ Biol Chem
PubMed ID9405450
'Mercuric chloride (HgCl2) induces T helper 2 (Th2) autoreactive anti-class II T cells in Brown Norway rats. These cells produce interleukin (IL)-4 and induce a B cell polyclonal activation that is responsible for autoimmune disease. In Brown Norway rats, HgCl2 triggers early IL-4 mRNA expression both in vivo and in ... More
Calcium permeability of the neuronal nuclear envelope: evaluation using confocal volumes and intracellular perfusion.
AuthorsO'Malley DM
JournalJ Neurosci
PubMed ID7931542
'In many calcium-imaging studies, the nuclear envelope appears to maintain a gradient of free calcium between the nucleus and cytosol. This issue was examined by loading amphibian sympathetic neurons with the calcium indicator fluo 3 via whole-cell patch clamping. Confocal optical sectioning allowed acquisition of independent calibration curves for the ... More
A study of the fluorescence measurement using a 96-well microplate by a remodelled parallel luminescent measuring system.
AuthorsKumae T
JournalLuminescence
PubMed ID10602312
'To develop an index to measure alveolar macrophage activity, the fluorescent technique for detection of calcium flux was paid special attention. In this study, a parallel luminescence measuring system was remodelled for fluorescence measurement using a 96-well microplate. The fluorescence indicators widely used to measure cytosolic free calcium ion concentration ... More
Ca2+ sparks triggered by patch depolarization in rat heart cells.
AuthorsShorofsky SR, Izu L, Wier WG, Balke CW
JournalCirc Res
PubMed ID9506702
'The goal of this study was to examine the relationship between Ca2+ entry through L-type Ca2+ channels and local [Ca2+]i transients (Ca2+ sparks) in single rat cardiac ventricular cells. L-type Ca2+ channels were activated by depolarization of cell-attached membrane patches, and [Ca2+]i was measured simultaneously as fluo 3 fluorescence using ... More
Comparison of human recombinant adenosine A2B receptor function assessed by Fluo-3-AM fluorometry and microphysiometry.
AuthorsPatel H, Porter RH, Palmer AM, Croucher MJ
JournalBr J Pharmacol
PubMed ID12598421
'1. The aim of this study was to establish the utility of a fluorometric imaging plate reader (FLIPR) assay to assess human adenosine A(2B) receptor function by characterizing its receptor pharmacology and comparing this profile to that obtained using a microphysiometer. 2. FLIPR was used, in conjunction with a Ca(2+)-sensitive ... More
Comparison of sarcoplasmic reticulum Ca2+-ATPase function in human, dog, rabbit, and mouse ventricular myocytes.
AuthorsSu Z, Li F, Spitzer KW, Yao A, Ritter M, Barry WH
JournalJ Mol Cell Cardiol
PubMed ID12818566
'It has been reported that sarcoplasmic reticulum (SR) Ca(2+) uptake is more rapid in rat than rabbit ventricular myocytes, but little information is available on the relative SR Ca(2+) uptake activity in others species, including humans. We induced Ca(2+) transients with a short caffeine pulse protocol (rapid solution switcher, 10 ... More
Imaging single cardiac ryanodine receptor Ca2+ fluxes in lipid bilayers.
'In this and an accompanying report we describe two steps, single-channel imaging and channel immobilization, necessary for using optical imaging to analyze the function of ryanodine receptor (RyR) channels reconstituted in lipid bilayers. An optical bilayer system capable of laser scanning confocal imaging of fluo-3 fluorescence due to Ca2+ flux ... More
Effects of gallium nitrate on calcium transients in UMR-106 rat osteoblastic osteosarcoma cells.
AuthorsLakatos P, Tatrai A, Stern PH
JournalBone
PubMed ID1419379
'Gallium nitrate is an effective antihypercalcemic and antiresorptive agent. Although its effects on osteoclasts are well documented, the mechanism of action of gallium nitrate on osteoblasts is still not established. To determine the effects of gallium nitrate on calcium signalling, we studied its effects on intracellular calcium concentration in UMR-106 ... More
Increased internal Ca2+ mediates neural induction in the amphibian embryo.
AuthorsMoreau M, Leclerc C, Gualandris-Parisot L, Duprat AM
JournalProc Natl Acad Sci U S A
PubMed ID7809092
'The molecular mechanism of neural induction is still unknown and the identity of the natural inducer remains elusive. It has been suggested that both the protein kinase C and cAMP signal transduction pathways may be involved in mediating its action. Here we provide evidence that Ca2+ is implicated in the ... More
Effects of 8-bromo-cyclic GMP on membrane potential of single swine tracheal smooth muscle cells.
AuthorsChoi J, Farley JM
JournalJ Pharmacol Exp Ther
PubMed ID9580602
'Cyclic GMP relaxes swine tracheal smooth muscle. Relaxation occurs because of decreases in intracellular calcium concentration ([Ca++]i) that are thought to occur through hyperpolarization which inhibits calcium influx. Activation of K+ channels has been suggested as the underlying mechanism for the hyperpolarization. In the present study, the effects of 8-bromoguanosine ... More
Depletion of intracellular Ca2+ stores sensitizes the flow-induced Ca2+ influx in rat endothelial cells.
AuthorsKwan HY, Leung PC, Huang Y, Yao X
JournalCirc Res
PubMed ID12595340
'Hemodynamic shear stress elicits a rise in endothelial [Ca2+]i, which may serve as a key second messenger to regulate many flow-associated physiological and biochemical processes. In the present study, we used Mn2+ quenching of fluorescent dye Fluo3 as an assay to investigate the Ca2+ influx of rat aortic endothelial cells ... More
Thapsigargin activates a calcium influx pathway in the unfertilized mouse egg and suppresses repetitive calcium transients in the fertilized egg.
AuthorsKline D, Kline JT
JournalJ Biol Chem
PubMed ID1387638
'At fertilization, the sperm initiates development of the mouse egg by inducing a large transient increase in the intracellular Ca2+ concentration ([Ca2+]i), which is followed by repetitive transient increases in [Ca2+]i. To determine how the repetitive Ca2+ transients are produced, thapsigargin, an inhibitor of the endoplasmic reticulum Ca-ATPase, was used ... More
Phototropism and geotropism in maize coleoptiles are spatially correlated with increases in cytosolic free calcium.
AuthorsGehring CA, Williams DA, Cody SH, Parish RW
JournalNature
PubMed ID11540625
'Phototropism and gravitropism in the shoots and roots of higher plants are the result of asymmetric growth. This is explained by the redistribution of growth regulators following exposure to gravity or unilateral light (the Cholodny-Went hypothesis). The positive phototropism and the negative geotropism of grass seedling coleoptiles are believed to ... More
Nongenomic effects of androstenedione on human granulosa luteinizing cells.
AuthorsMachelon V, Nomé F, Tesarik J
JournalJ Clin Endocrinol Metab
PubMed ID9435453
'This study examines rapid (5-60 s) effects of androgens on the cytosolic free Ca2+ concentration ([Ca2+]i) in human granulosa lutenizing cells. Cells were obtained from human preovulatory follicles, and [Ca2+]i was measured with the use of the Ca(2+)-responsive fluorescent dye fluo-3. Molar concentrations between 100 pmol/L and 1 mumol/L androstenedione ... More
Bradykinin induced a positive chronotropic effect via stimulation of T- and L-type calcium currents in heart cells.
AuthorsEl-Bizri N, Bkaily G, Wang S, Jacques D, Regoli D, D'Orléans-Juste P, Sukarieh R
JournalCan J Physiol Pharmacol
PubMed ID12733823
'Using Fluo-3 calcium dye confocal microscopy and spontaneously contracting embryonic chick heart cells, bradykinin (10(-10) M) was found to induce positive chronotropic effects by increasing the frequency of the transient increase of cytosolic and nuclear free Ca2+. Pretreatment of the cells with either B1 or B2 receptor antagonists (R126 and ... More
Functional screening of intracellular proteins in single cells and in patterned cell arrays using electroporation.
AuthorsNolkrantz K, Farre C, Hurtig KJ, Rylander P, Orwar O
JournalAnal Chem
PubMed ID12199607
'A tool for detection and characterization of intracellular enzyme-substrate and receptor-ligand interactions inside the cytoplasm of single targeted cells or small confined groups of cells is presented. Fluorogenic enzyme substrates and receptor ligands were rapidly delivered by electroosmosis and internalized by electroporation in cells using an electrolyte-filled capillary (EFC) biased ... More
Imaging the hierarchical Ca2+ signalling system in HeLa cells.
AuthorsBootman M, Niggli E, Berridge M, Lipp P
JournalJ Physiol
PubMed ID9080361
'1. Confocal microscopy was used to investigate hormone-induced subcellular Ca2+ release signals from the endoplasmic reticulum (ER) in a prototype non-excitable cell line (HeLa cells). 2. Histamine application evoked two types of elementary Ca2+ signals: (i) Ca2+ blips arising from single ER Ca2+ release channels (amplitude, 30 nM; lateral spreading, ... More
Interleukin-13 inhibits protein kinase C-triggered respiratory burst in human monocytes. Role of calcium and cyclic AMP.
AuthorsSozzani P, Cambon C, Vita N, Séguélas MH, Caput D, Ferrara P, Pipy B
JournalJ Biol Chem
PubMed ID7890616
'Interleukin-13 (IL-13), a novel cytokine produced by activated lymphocytes modulates some monocyte functions, but no data is available concerning the signal transduction pathway. We show here, the inhibitory effect of IL-13 on 12-O-tetradecanoylphorbol-13-acetate (TPA)-triggered reactive oxygen intermediate production in human monocytes and the signals involved in this response. Our results ... More
Spectral studies on the calcium-binding properties of Mts1 protein and its interaction with target protein.
AuthorsDukhanina EA, Dukhanin AS, Lomonosov MY, Lukanidin EM, Georgiev GP
JournalFEBS Lett
PubMed ID9237671
'Two calcium-binding sites of the Mts1 protein, a member of S-100 protein family, were distinguished with the Fluo-3 fluorescent technique. The geometric mean of the apparent dissociation constant (Kd) for these two sites is 2.6 microM; the Hill coefficient (nH) is 0.98. In the presence of a novel target protein ... More
Electrofusion-induced intracellular Ca2+ flux and its effect on murine oocyte activation.
AuthorsRickords LF, White KL
JournalMol Reprod Dev
PubMed ID1599684
'These experiments were designed to monitor influx of extracellular Ca2+ into the murine ooplasm following a 1.56 kV.cm-1 direct current (DC) electrofusion pulse and subsequently to determine its effect on rate of activation. Pulse media consisted of non-electrolyte (0.3 M mannitol) and electrolyte (phosphate-buffered saline; PBS) media each containing 0.0, ... More
Mitochondrial calcium spiking: a transduction mechanism based on calcium-induced permeability transition involved in cell calcium signalling.
AuthorsIchas F, Jouaville LS, Sidash SS, Mazat JP, Holmuhamedov EL
JournalFEBS Lett
PubMed ID8034044
'We report reversible Ca(2+)-induced Ca2+ release from mitochondria, which takes the form of Ca2+ spikes. Mitochondrial Ca2+ spiking is an all-or-none process with a threshold dependence on both the frequency and the amplitude of the Ca2+ pulses used as stimuli. This spiking relies on the transient operation of the mitochondrial ... More
Suppression by staurosporine of Ca(2+)-mobilization triggered by ligation of antigen-specific receptors on t and B lymphocytes. An essential role of protein tyrosine kinase in the signal transduction.
AuthorsYamashita Y, Hasegawa-Sasaki H, Sasaki T
JournalFEBS Lett
PubMed ID1879563
'It is known that the receptor for platelet-derived growth factor (PDGF) activates phospholipase C (PLC) by phosphorylating the gamma 1 isoform of PLC with the receptor protein-tyrosine kinase (PTK), whereas a guanine nucleotide-binding protein participates as a transducer in the PLC activation through the receptors for vasopressin, bombesin and prostaglandin ... More