Electrical and chemical excitability appear one week before birth in the embryonic rat spinal cord.
AuthorsMandler RN, Schaffner AE, Novotny EA, Lange GD, Smith SV, Barker JL
JournalBrain Res
PubMed ID1699635
'Embryonic rat spinal cord cells were acutely dissociated with the enzyme papain, stained with a voltage-sensitive oxonol dye and incubated with various pharmacological agents. Changes in the fluorescence intensity and, by inference, membrane potential of the cells were analyzed in a flow cytometer. Veratridine caused depolarization of the cells in ... More
Voltage-sensitive oxonol dyes are novel large-conductance Ca2+-activated K+ channel activators selective for beta1 and beta4 but not for beta2 subunits.
'The large-conductance Ca(2+)-activated K(+) (BK) channel is activated by both the increase of intracellular Ca(2+) concentration and membrane depolarization. The BK channel plays crucial roles as a key molecule in the negative feedback mechanism regulating membrane excitability and cellular Ca(2+) in various cell types. Here, we report that a widely ... More
Bretylium causes a K(+)-Na+ pump activation that is independent of Na+/H+ exchange in depolarized rat, mouse and human lymphocytes.
AuthorsTrón L, Pieri C, Márián T, Balkay L, Emri M, Damjanovich S
JournalMol Immunol
PubMed ID2177149
'We have studied a bretylium tosylate induced increase of the membrane potentials of partially depolarized rat, mouse and human lymphocytes, using the potential sensitive dye, bis [1,3, dibutylbarbituric acid-(5) trimethine oxonol]. The extent of this repolarization is dose-dependent and decreased in magnitude as the temp was reduced from 37 degrees ... More
Mechanism through which GABAA receptor modulates catecholamine secretion from bovine chromaffin cells.
AuthorsGonzalez MP, Oset-Gasque MJ, Castro E, Bugeda J, Arce C, Parramon M
JournalNeuroscience
PubMed ID1322511
'The actions and mechanism of GABAergic modulation of catecholamine secretion from isolated bovine chromaffin cells were investigated. The GABAA receptor agonist muscimol induced a fast rise in cytosolic [Ca2+]. The mean peak increase was 290 +/- 30 nM over basal levels. The increase in cytosolic [Ca2+] was abolished in the ... More
GABAergic cells and signals appear together in the early post-mitotic period of telencephalic and striatal development.
AuthorsFiszman ML, Behar T, Lange GD, Smith SV, Novotny EA, Barker JL
JournalBrain Res Dev Brain Res
PubMed ID8394789
'Single cell suspensions derived from embryonic telencephala taken from embryos of gestational day 13 (E13) as well as rat striatal tissue from E14, 15 and 17 were prepared by tissue digestion with papain. Cell suspensions were analyzed by flow cytometry or plated onto poly-D-lysine-coated culture dishes for either nuclear staining ... More
Flow cytometric analysis of membrane potential in embryonic rat spinal cord cells.
AuthorsMandler RN, Schaffner AE, Novotny EA, Lange GD, Barker JL
JournalJ Neurosci Methods
PubMed ID3361946
'Flow cytometric analysis of membrane potential in suspensions of embryonic rat spinal cord cells was carried out in a fluorescence-activated cell sorter (FACS) using anionic voltage-sensitive, fluorescent dyes (oxonols). The FACS or flow cytometer is an analytical instrument that measures optical properties of large cell populations at a single cell ... More
Distribution of GABA(C)-like responses among acutely dissociated rat retinal neurons.
AuthorsNelson R, Schaffner AE, Li YX, Walton MK
JournalVis Neurosci
PubMed ID10022489
'GABAergic responses of acutely dissociated rat retinal neurons, including both bipolar cells (BCs) and other, morphologically round cells (RCs), were assayed with the fluorescent (FL), voltage-sensitive probe oxonol DiBaC4(5). Using intensified video microscopy and simultaneous recording, GABA responses were identified in one-third of cells in a typical microscope field; of ... More
Sequence of metabolic changes during X-ray-induced apoptosis.
AuthorsFerlini C, De Angelis C, Biselli R, Distefano M, Scambia G, Fattorossi A
JournalExp Cell Res
PubMed ID10047458
'A cell population undergoing apoptosis usually contains varying proportions of cells in the diverse stages of the process, from very early continuously through to secondary necrosis. This heterogeneity acts as a confounding factor in metabolic studies if a general population is investigated. Using fluorescent probes and multiparameter flow cytometry, we ... More
Mechanism of potential-dependent light absorption changes of lipid bilayer membranes in the presence of cyanine and oxonol dyes.
AuthorsWaggoner AS, Wang CH, Tolles RL
JournalJ Membr Biol
PubMed ID864684
Dye indicators of membrane potential.
AuthorsWaggoner AS
JournalAnnu Rev Biophys Bioeng
PubMed ID383007
Kinetics of the association of potential-sensitive dyes with model and energy-transducing membranes: implications for fast probe response times.
AuthorsSmith JC, Frank SJ, Bashford CL, Chance B, Rudkin B
JournalJ Membr Biol
PubMed ID7401166
Mechanisms of rapid optical changes of potential sensitive dyes.
AuthorsWaggoner AS, Grinvald A
JournalAnn N Y Acad Sci
PubMed ID290293
Imaging membrane potential with voltage-sensitive dyes.
AuthorsZochowski M, Wachowiak M, Falk CX, Cohen LB, Lam YW, Antic S, Zecevic D
JournalBiol Bull
PubMed ID10707808
Membrane potential can be measured optically using a variety of molecular probes. These measurements can be useful in studying function at the level of an individual cell, for determining how groups of neurons generate a behavior, and for studying the correlated behavior of populations of neurons. Examples of the three ... More
Dual-fluorescence flow cytometric analysis of membrane potential and cytoplasmic free Ca2+ concentration in embryonic rat hippocampal cells.
AuthorsMitsumoto Y, Mohri T
JournalCell Struct Funct
PubMed ID2560680
We have demonstrated simultaneous measurement of the membrane potential and cytoplasmic free Ca2+ concentration ([Ca2+]i) by utilizing a dual-laser flow cytometer in embryonic rat hippocampal cell suspensions. Veratrine, a Na+ channel activator, induced both membrane depolarization and elevation of [Ca2+]i. These actions of veratrine were all reversed by the presence ... More
Metabolic effects of some electrofluorimetric dyes.
AuthorsKinnally KW, Tedeschi H
JournalBiochim Biophys Acta
PubMed ID687611
The effect of five electrofluorimetric dyes on mitochondrial metabolism was examined to determine their suitability for mitochondrial studies and other biological uses. The dyes merocyanine 540, 8-anilino-1-naphthalene sulfonic acid and bis(1,3-dibutyl barbituric acid-(5))-pentamethane oxonol were found to be inhibitors of the respiratory chain. However, the first two exerted their effect ... More
Use of dyes to estimate the electrical potential of the mitochondrial membrane.
AuthorsKinnally KW, Tedeschi H, Maloff BL
JournalBiochemistry
PubMed ID687593
A number of cationic or anionic fluorescent dyes were investigated as possible monitors of the membrane potential of rat liver mitochondria, and giant mitochondria isolated from the liver of mice maintained on a diet containing cuprizone. The fluorescence of four dyes (8-anilino-1-naphthalenesulfonic acid, merocyanine 540, 3,3'-dipropyl-thiocarbocyanine, and bis[1,3-dibutylbarbituric acid-(5)]-pentamethine oxonol) ... More
Flow cytometric detection of membrane potential changes in murine lymphocytes induced by concanavalin A.
AuthorsTatham PE, Delves PJ
JournalBiochem J
PubMed ID6540562
The effect of the mitogenic lectin concanavalin A on the membrane potential of murine lymphocytes was investigated by observing the fluorescence of cells stained with carbocyanine and oxonol dyes. We describe a rapid and reliable method for detecting lectin-induced membrane potential changes in individual cells by flow cytometric analysis of ... More
Optical probe responses on sarcoplasmic reticulum. Merocyanine and oxonol dyes.
AuthorsRussell JT, Beeler T, Martonosi A
JournalJ Biol Chem
PubMed ID422566
The fluorescence and absorbance of merocyanine 540 in suspensions of skeletal muscle microsomes is altered by the binding of Ca2+ and other cations to the membrane. The order of effectiveness of various cations in causing this effect is La greater than Ca congruent to Mg greater than K. Competition between ... More
Differential inhibition of AE1 and AE2 anion exchangers by oxonol dyes and by novel polyaminosterol analogs of the shark antibiotic squalamine.
AuthorsAlper SL, Chernova MN, Williams J, Zasloff M, Law FY, Knauf PA
JournalBiochem Cell Biol
PubMed ID10353714
Oxonol and polyaminosterol drugs were examined as inhibitors of recombinant mouse AE1 and AE2 anion exchangers expressed in Xenopus laevis oocytes and were compared as inhibitors of AE1-mediated anion flux in red cells and in HL-60 cells that express AE2. The oxonols WW-781, diBA(5)C4, and diBA(3)C4 inhibited HL-60 cell Cl-/Cl- ... More
Stimulation of leucine transport by a mitogen through intracellular Ca2+ increase in human peripheral lymphocytes.
AuthorsMitsumoto Y, Sato K, Mohri T
JournalBiochim Biophys Acta
PubMed ID3125859
The effect of concanavalin A and ionophore A23187 on leucine uptake by human peripheral lymphocytes has been examined. Preincubation of the cells with 32 micrograms/ml concanavalin A or 0.1 microM A23187 increased leucine uptake by 67% and 100%, respectively. Both concanavalin A and A23187 could, within 2 min, induce a ... More
Characterization of an electrogenic ATP and chloride-dependent proton translocating pump from rat renal medulla.
AuthorsKaunitz JD, Gunther RD, Sachs G
JournalJ Biol Chem
PubMed ID2995342
To study acidification mechanisms in the distal nephron, microsomes were prepared from rat renal medulla by differential centrifugation. Microsomes were enriched in the enzyme marker gamma-glutamyl transferase and contained an ATP-dependent proton pump, as evidenced by ATP-dependent, 3,3',4',5-tetrachlorosalicylanilide-reversible quenching of acridine orange fluorescence. Acidification was vanadate-insensitive, but was completely inhibited ... More
An oxonol dye is the most potent known inhibitor of band 3-mediated anion exchange.
AuthorsKnauf PA, Law FY, Hahn K
JournalAm J Physiol
PubMed ID7485448
When cells are acutely exposed to the oxonol dye, bis(1,3-dibutylbarbituric acid)pentamethine oxonol (diBA), at 0 degrees C, the concentration that gives half inhibition of Cl- exchange (IC50) is 0.146 +/- 0.013 microM (n = 12) initially, but the inhibition increases with time. These characteristics indicate that a rapid initial binding ... More
Sodium channels, GABAA receptors, and glutamate receptors develop sequentially on embryonic rat spinal cord cells.
AuthorsWalton MK, Schaffner AE, Barker JL
JournalJ Neurosci
PubMed ID8386754
It is not well understood when during embryonic development the elements of a cell's responsiveness first appear, nor the factors controlling their appearance. A strategy to approach this issue is to determine which aspects of neuronal development are highly stereotyped in presence, timing, or pattern across a variety of cell ... More
Murine T lymphocytes modulate activity of an ATP-activated P2Z-type purinoceptor during differentiation.
AuthorsChused TM, Apasov S, Sitkovsky M
JournalJ Immunol
PubMed ID8759716
Murine T, but not B, lymphocytes constitutively express a membrane receptor for adenosine nucleotides that opens a nonspecific pore that admits Ca2+ and ethidium (314 Da), but not propidium (415 Da) ions. ATP, ADP, and AMP show decreasing potency; UTP and adenosine are inactive. Nonhydrolyzable ATP analogues are completely ineffective. ... More
Acute hypoxia causes membrane depolarization and calcium influx in fetal pulmonary artery smooth muscle cells.
Changes in oxygen tension in the perinatal period contribute to high pulmonary vascular tone in the fetus and the decline in resistance that occurs at birth. Distal pulmonary artery smooth muscle cells (PASMC) isolated from late-gestation ovine fetuses respond to acute hypoxia with an increase in cytosolic calcium concentration ([Ca2+]i) ... More
Volume-activated chloride channels in HL-60 cells: potent inhibition by an oxonol dye.
AuthorsArreola J, Hallows KR, Knauf PA
JournalAm J Physiol
PubMed ID7485447
When swollen in hypotonic media, HL-60 cells exhibit a regulatory volume decrease (RVD) response as a result of net losses of K+ and Cl-. This is primarily caused by a dramatic increase in Cl- permeability, which may reflect the opening of volume-sensitive channels (11). To test this hypothesis, we measured ... More
In situ measurement of the electrical potential across the phagosomal membrane using FRET and its contribution to the proton-motive force.
AuthorsSteinberg BE, Touret N, Vargas-Caballero M, Grinstein S
JournalProc Natl Acad Sci U S A
PubMed ID17517624
Phagosomes employ lytic enzymes, cationic peptides, and reactive oxygen intermediates to eliminate invading microorganisms. The effectiveness of these microbicidal mechanisms is potentiated by the acidic pH created by H(+)-pumping vacuolar-type ATPases (V-ATPases) on the phagosomal membrane. The degree of phagosomal acidification varies greatly among neutrophils, macrophages, and dendritic cells and ... More
Embryonic and early postnatal hippocampal cells respond to nanomolar concentrations of muscimol.
AuthorsFiszman ML, Novotny EA, Lange GD, Barker JL
JournalBrain Res Dev Brain Res
PubMed ID2357791
Embryonic and early postnatal tissue taken from rat hippocampi were papain digested in order to obtain cell suspensions suitable for analysis in a fluorescence-activated cell sorter (FACS). Cell suspensions consisted of two major peaks of forward-angle light scatter (FALS). FACS analysis showed that the population which stained intensely with the ... More