Noninvasive measurement of chloride concentration in rat olfactory receptor cells with use of a fluorescent dye.
AuthorsKaneko H, Nakamura T, Lindemann B
JournalAm J Physiol Cell Physiol
PubMed ID11350733
Inwardly directed Ca(2+)-dependent chloride currents are thought to prolong and boost the odorant-induced transient receptor currents in olfactory cilia. Cl(-) inward current, of course, requires a sufficiently high intracellular Cl(-) concentration ([Cl(-)](i)). In previous measurements using a fluorescent Cl(-) probe, N-(ethoxycarbonylmethyl)-6-methoxyquinolinium bromide (MQAE), [Cl(-)](i) of newt olfactory cells was estimated ... More
TRPV1 acts as proton channel to induce acidification in nociceptive neurons.
AuthorsHellwig N, Plant TD, Janson W, Schäfer M, Schultz G, Schaefer M
JournalJ Biol Chem
PubMed ID15173182
The low extracellular pH of inflamed or ischemic tissues enhances painful sensations by sensitizing and activating the vanilloid receptor 1 (TRPV1). We report here that activation of TRPV1 results in a marked intracellular acidification in nociceptive dorsal root ganglion neurons and in a heterologous expression system. A characterization of the ... More
Mechanistic studies of lantibiotic-induced permeabilization of phospholipid vesicles.
AuthorsDriessen AJ, van den Hooven HW, Kuiper W, van de Kamp M, Sahl HG, Konings RN, Konings WN
JournalBiochemistry
PubMed ID7849020
'Nisin is a cationic polycyclic bacteriocin secreted by some lactic acid bacteria. Nisin has previously been shown to permeabilize liposomes. The interaction of nisin was analyzed with liposomes prepared of the zwitterionic phosphatidylcholine (PC) and the anionic phosphatidylglycerol (PG). Nisin induces the release of 6-carboxyfluorescein and other small anionic fluorescent ... More
Determination of the intracellular free chloride concentration in rat brain synaptoneurosomes using a chloride-sensitive fluorescent indicator.
AuthorsEngblom AC, Akerman KE
JournalBiochim Biophys Acta
PubMed ID8274496
'The chloride-sensitive fluorescent indicator MQAE (N-(6-methoxyquinolyl) acetoacetyl ester) has been used for determination of the intracellular free chloride concentration in rat brain synaptoneurosomes. Loading of the synaptoneurosomes with MQAE occurs by transmembrane diffusion. Calibration of the intracellular MQAE was done by determining the correlation between fluorescence intensity and intrasynaptoneurosomal Cl- ... More
Effects of sasanquasaponin on ischemia and reperfusion injury in mouse hearts.
AuthorsLai ZF, Shao Z, Chen YZ, He M, Huang Q, Nishi K
JournalJ Pharmacol Sci
PubMed ID15037817
'We investigated effects of sasanquasaponin (SQS), a traditional Chinese herb''s effective component, on ischemia and reperfusion injury in mouse hearts and the possible role of intracellular Cl- homeostasis on SQS''s protective effects during ischemia and reperfusion. An in vivo experimental ischemia model was made in mice (weight 27-45 g) using ... More
Human cytomegalovirus infection stimulates Cl-/HCO-3 exchanger activity in human fibroblasts.
AuthorsMaglova LM, Crowe WE, Altamirano AA, Russell JM
JournalAm J Physiol
PubMed ID9688606
'The effects of human cytomegalovirus (HCMV) infection on Cl-/HCO-3 exchanger activity in human lung fibroblasts (MRC-5 cells) were studied using fluorescent, ion-sensitive dyes. The intracellular pH (pHi) of mock- and HCMV-infected cells bathed in a solution containing 5% CO2-25 mM HCO-3 were nearly the same. However, replacement of external Cl- ... More
Assessment of swelling-activated Cl- channels using the halide-sensitive fluorescent indicator 6-methoxy-N-(3-sulfopropyl)quinolinium.
AuthorsSrinivas SP, Bonanno JA, Hughes BA
JournalBiophys J
PubMed ID9649372
'This study describes a quantitative analysis of the enhancement in anion permeability through swelling-activated Cl- channels, using the halide-sensitive fluorescent dye 6-methoxy-N-(3-sulfopropyl)quinolinium (SPQ). Cultured bovine corneal endothelial monolayers perfused with NO3- Ringer''s were exposed to I- pulses under isosmotic and, subsequently, hyposmotic conditions. Changes in SPQ fluorescence due to I- ... More
Site-directed mutagenesis identifies residues in uncoupling protein (UCP1) involved in three different functions.
AuthorsEchtay KS, Winkler E, Bienengraeber M, Klingenberg M
JournalBiochemistry
PubMed ID10727223
'Using site-specific mutagenesis, we have constructed several mutants of uncoupling protein (UCP1) from brown adipose tissue to investigate the function of acidic side chains at positions 27, 167, 209, and 210 in H(+) and Cl(-) transport as well as in nucleotide binding. The H(+) transport activity was measured with mitochondria ... More
In the uncoupling protein (UCP-1) His-214 is involved in the regulation of purine nucleoside triphosphate but not diphosphate binding.
AuthorsEchtay KS, Bienengraeber M, Winkler E, Klingenberg M
JournalJ Biol Chem
PubMed ID9733725
'The nucleotide binding to uncoupling protein (UCP-1) of brown adipose tissue is regulated by pH. The binding pocket of the nucleotide phosphate moiety has been proposed to be controlled by the protonization of a carboxyl group (pK approximately 4.5) for both nucleoside diphosphates (NDP) and nucleoside triphosphates (NTP) (identified as ... More
Intracellular pH regulation in cultured astrocytes from rat hippocampus. II. Electrogenic Na/HCO3 cotransport.
AuthorsBevensee MO, Apkon M, Boron WF
JournalJ Gen Physiol
PubMed ID9379176
'In the preceding paper (Bevensee, M.O., R.A. Weed, and W.F. Boron. 1997. 110: 453-465.), we showed that a Na-driven influx of HCO causes the increase in intracellular pH (pH) observed when astrocytes cultured from rat hippocampus are exposed to 5% CO/17 mM HCO. In the present study, we used the ... More
Cl- transport in an immortalized human epithelial cell line (NCM460) derived from the normal transverse colon.
'Cells of a newly described, immortalized, epithelial, human transverse colonic cell line, NCM460, reach approximately 90% confluence on plastic and develop transepithelial resistances of 120-250 Omega . cm2 on porous substrates. Its utility as a model for the transverse human colon was validated by comparing second messenger-mediated Cl- transport, using ... More
Development and biological applications of chloride-sensitive fluorescent indicators.
AuthorsVerkman AS
JournalAm J Physiol
PubMed ID2205105
'Chloride movement across cell plasma and internal membranes, is of central importance for regulation of cell volume and pH, vectorial salt movement in epithelia, and, probably, intracellular traffic. Quinolinium-based chloride-sensitive fluorescent indicators provide a new approach to study chloride transport mechanisms and regulation that is complementary to 36Cl tracer methods, ... More
Determination of chloride efflux by X-ray microanalysis versus MQAE-fluorescence.
AuthorsAndersson C, Roomans GM
JournalMicrosc Res Tech
PubMed ID12467030
'The importance of chloride channels for the cell is demonstrated by a number of serious human diseases that are due to mutations in chloride channels. The most well-known of these diseases is cystic fibrosis. Investigations into the mechanisms of the disease and possible treatments require the study of chloride fluxes ... More
Unusually common cystic fibrosis mutation in Portugal encodes a misprocessed protein.
AuthorsMendes F, Roxo Rosa M, Dragomir A, Farinha CM, Roomans GM, Amaral MD, Penque D
JournalBiochem Biophys Res Commun
PubMed ID14623323
'A561E, a novel cystic fibrosis (CF) associated mutation in the first nucleotide binding domain of CFTR, is the second most common CF mutation in Portugal. Properties of the A561E-CFTR protein were studied by immunoblotting, pulse-chase, immunocytochemistry, and MQAE halide-efflux assay in stably transfected BHK cells. Altogether, results presented here suggest ... More
A molecular mechanism for aberrant CFTR-dependent HCO(3)(-) transport in cystic fibrosis.
AuthorsKo SB, Shcheynikov N, Choi JY, Luo X, Ishibashi K, Thomas PJ, Kim JY, Kim KH, Lee MG, Naruse S, Muallem S
JournalEMBO J
PubMed ID12411484
'Aberrant HCO(3)(-) transport is a hallmark of cystic fibrosis (CF) and is associated with aberrant Cl(-)-dependent HCO(3)(-) transport by the cystic fibrosis transmembrane conductance regulator (CFTR). We show here that HCO(3)(-) current by CFTR cannot account for CFTR-activated HCO(3)(-) transport and that CFTR does not activate AE1-AE4. In contrast, CFTR ... More
Delayed shortening and shrinkage of cochlear outer hair cells.
AuthorsOhnishi S, Hara M, Inoue M, Yamashita T, Kumazawa T, Minato A, Inagaki C
JournalAm J Physiol
PubMed ID1443102
'Slow shortening of cochlear outer hair cells has been speculated to modify cochlear sensitivity. Tetanic electrical field stimulation of isolated outer hair cells from guinea pigs shortened the cells for 2-3 min. Electrical stimulation reduced cell length and volume (-13.5 +/- 1.5 and -37.3 +/- 3.0% of initial values, respectively, ... More
Permeation of halide anions through phospholipid bilayers occurs by the solubility-diffusion mechanism.
AuthorsPaula S, Volkov AG, Deamer DW
JournalBiophys J
PubMed ID9449332
'Two alternative mechanisms are frequently used to describe ionic permeation of lipid bilayers. In the first, ions partition into the hydrophobic phase and then diffuse across (the solubility-diffusion mechanism). The second mechanism assumes that ions traverse the bilayer through transient hydrophilic defects caused by thermal fluctuations (the pore mechanism). The ... More
Thallium mediates a rapid chloride/hydroxyl ion exchange through myelin lipid bilayers.
AuthorsDíaz RS, Monreal J
JournalMol Pharmacol
PubMed ID7808444
'We have investigated the effects of several heavy metal cations on the proton and chloride permeabilities of liposomes prepared with endogenous lipids from brain myelin, by monitoring the fluorescence emitted by acridine orange and N-(6-methoxyquinolyl)acetoethyl ester. In addition to Hg2+ and Cu+, nanomolar concentrations of Tl3+, but not Tl+, were ... More
Na-independent Cl(-)-HCO3- exchange mediates recovery of pHi from alkalosis in guinea pig ventricular myocytes.
AuthorsXu P, Spitzer KW
JournalAm J Physiol
PubMed ID8048611
'The pH-sensitive fluorescent indicator, carboxy-seminaphthorhodafluor 1 (SNARF 1) was used to assess the contribution of forward Na-independent Cl(-)-HCO3- exchange (1 external Cl- exchanged for 1 internal HCO3-) to intracellular pH (pHi) recovery from alkalosis in adult ventricular myocytes (guinea pig). Intracellular alkalosis was elicited by external application of the weak ... More
Calcium-sensing receptor abrogates secretagogue- induced increases in intestinal net fluid secretion by enhancing cyclic nucleotide destruction.
AuthorsGeibel J, Sritharan K, Geibel R, Geibel P, Persing JS, Seeger A, Roepke TK, Deichstetter M, Prinz C, Cheng SX, Martin D, Hebert SC
JournalProc Natl Acad Sci U S A
PubMed ID16760252
'The calcium-sensing receptor (CaSR) provides a fundamental mechanism for diverse cells to detect and respond to modulations in the ionic and nutrient compositions of their extracellular milieu. The roles for this receptor are largely unknown in the intestinal tract, where epithelial cells are normally exposed to large variations in extracellular ... More
Ion transport during growth and differentiation.
AuthorsVenkatasubramanian J, Sahi J, Rao MC
JournalAnn N Y Acad Sci
PubMed ID11193599
'The major function of the adult colon is to reabsorb fluid from the chyme. This ability to conserve salt and water is especially important in newborns, where reserves are small and diarrhea is frequent. Although much is known about regulation of Cl- transport in the adult colon, postnatal changes in ... More
Two-photon chloride imaging in neurons of brain slices.
AuthorsMarandi N, Konnerth A, Garaschuk O
JournalPflugers Arch
PubMed ID12466938
'Two-photon laser scanning microscopy has been used successfully for imaging activity-dependent changes of intracellular calcium and sodium levels. Here we introduce a simple technique for two-photon chloride imaging in intact neurons. It involves the use of the membrane-permeable Cl(-) indicator dye MQAE [N-(6-methoxyquinolyl) acetoethyl ester]. Brief incubation with MQAE produced ... More
Fluorophore toxicity in mouse eggs and zygotes.
AuthorsPhillips KP, Zhou WL, Baltz JM
JournalZygote
PubMed ID9770776
'Ion-sensitive fluorophores are commonly used for quantitative measurements of intracellular ion concentrations. However, both the method of intracellular loading--which for many fluorophores involves endogenous esterase-mediated removal of hydrophobic groups such as acetoxymethyl esters (AM)--and fluorescence excitation of fluorophores in the cell, can produce toxic metabolites and reactive species. Techniques used ... More
Mechanisms of chloride transport in thymic lymphocytes.
AuthorsStakisaitis D, Lapointe MS, Batlle D
JournalAm J Physiol Renal Physiol
PubMed ID11208607
'This study examined mechanisms of Cl- transport in rat lymphocytes under a variety of conditions. Basal intracellular Cl- concentration ([Cl-]i) was not different between cells assayed in the presence of HCO3- or its absence (HEPES). Removal of external Cl- resulted in a fall in [Cl-]i and a rapid rise in ... More
On membrane motor activity and chloride flux in the outer hair cell: lessons learned from the environmental toxin tributyltin.
AuthorsSong L, Seeger A, Santos-Sacchi J
JournalBiophys J
PubMed ID15596517
'The outer hair cell (OHC) underlies mammalian cochlea amplification, and its lateral membrane motor, prestin, which drives the cell''s mechanical activity, is modulated by intracellular chloride ions. We have previously described a native nonselective conductance (G(metL)) that influences OHC motor activity via Cl flux across the lateral membrane. Here we ... More
Na+-K+-Cl- cotransport in human fibroblasts is inhibited by cytomegalovirus infection.
AuthorsMaglova LM, Crowe WE, Smith PR, Altamirano AA, Russell JM
JournalAm J Physiol
PubMed ID9814982
'We examined the effects of human cytomegalovirus (HCMV) infection on the Na+-K+-Cl- cotransporter (NKCC) in a human fibroblast cell line. Using the Cl--sensitive dye MQAE, we showed that the mock-infected MRC-5 cells express a functional NKCC. 1) Intracellular Cl- concentration ([Cl-]i) was significantly reduced from 53.4 +/- 3.4 mM to ... More
Activation of CFTR by genistein in human airway epithelial cell lines.
AuthorsAndersson C, Servetnyk Z, Roomans GM
JournalBiochem Biophys Res Commun
PubMed ID12914781
'Cystic fibrosis (CF) is caused by a mutation in the cystic fibrosis transmembrane conductance regulator (CFTR), a chloride channel expressed in epithelial cells. The effects of genistein and 4-phenylbutyrate (PBA) on CFTR were studied in three human airway epithelial cell lines expressing wild-type or DeltaF508 CFTR: Calu-3, CFSMEo-, and CFBE41o- ... More
Modulation of intracellular Cl- homeostasis by lectin-stimulation in Jurkat T lymphocytes.
AuthorsLai ZF, Chen YZ, Nishi K
JournalEur J Pharmacol
PubMed ID14659998
'We investigated changes in intracellular Cl(-) concentration ([Cl(-)](i)) during lectin-induced activation and proliferation in human Jurkat T lymphocytes. [Cl(-)](i) was measured using Cl(-) fluorescence dye (N-(6-methoyquinolyl) acetoxy-acetyl-ester, MQAE) methods. Lectins, phytohemagglutinin and concanavalin A, dose-dependently increased [Cl(-)](i) and triggered intracellular Cl(-) oscillation in human Jurkat T lymphocytes. However, some mitochondria ... More
Uneven distribution of intracellular Cl- in rat hippocampal neurons.
AuthorsHara M, Inoue M, Yasukura T, Ohnishi S, Mikami Y, Inagaki C
JournalNeurosci Lett
PubMed ID1436657
'Electrophysiological observations of neurons suggest that perikarya and dendrites differ in local intracellular Cl- concentration ([Cl-]i), that has not been demonstrated yet. Regional [Cl-]i in cultured hippocampal neurons was estimated using a Cl(-)-sensitive fluorescent dye. Calibration showed that perikaryonic [Cl-]i was lower than dendritic [Cl-]i. Ethacrynic acid, an inhibitor of ... More
Synthesis and characterization of improved chloride-sensitive fluorescent indicators for biological applications.
AuthorsVerkman AS, Sellers MC, Chao AC, Leung T, Ketcham R
JournalAnal Biochem
PubMed ID2751097
'A class of N-substituted quinoline compounds has been introduced recently for the fluorescence measurement of Cl concentration in biological preparations. The most Cl-sensitive compound was 6-methoxy-N-[3-sulfopropyl] quinolinium with peak excitation and emission wavelengths of 350 and 442 nm and a Stern-Volmer constant for quenching by Cl of 118 M-1. Six ... More
Fluorescence-optical measurements of chloride movements in cells using the membrane-permeable dye diH-MEQ.
AuthorsWöll E, Gschwentner M, Fürst J, Hofer S, Buemberger G, Jungwirth A, Frick J, Deetjen P, Paulmichl M
JournalPflugers Arch
PubMed ID8766008
'Fluorescence-optical measurements of the intracellular chloride concentration facilitate identification of chloride movements across the cell membrane of living cells. The two main dyes used for this purpose are 6-methoxy-N-(3-sulfopropyl)quinolinium (SPQ) and 6-methoxy-quinolyl acetoethyl ester (MQAE). The use of both substances is impaired by their poor membrane permeability and therefore limited ... More
An ATP-driven Cl- pump regulates Cl- concentrations in rat hippocampal neurons.
AuthorsInoue M, Hara M, Zeng XT, Hirose T, Ohnishi S, Yasukura T, Uriu T, Omori K, Minato A, Inagaki C
JournalNeurosci Lett
PubMed ID1667680
'To investigate the role of Cl(-)-stimulated Mg(2+)-ATPase (Cl(-)-ATPase) in neurons, we examined the effects of ethacrynic acid (0.3 mM), which completely inhibits Cl(-)-ATPase on the intracellular Cl- concentrations of cultured rat hippocampal neurons, using Cl(-)-sensitive fluorescent probes. Ethacrynic acid and ATP consuming treatment increased the intracellular Cl- concentration, but elevation ... More
NarK is a nitrite-extrusion system involved in anaerobic nitrate respiration by Escherichia coli.
Escherichia coli can use nitrate as a terminal electron acceptor for anaerobic respiration. A polytopic membrane protein, termed NarK, has been implicated in nitrate uptake and nitrite excretion and is thought to function as a nitrate/nitrite antiporter. The longest-lived radioactive isotope of nitrogen, 13N-nitrate (half-life = 9.96 min) and the ... More
Direct measurement of the chloride concentration in newt olfactory receptors with the fluorescent probe.
AuthorsNakamura T, Kaneko H, Nishida N
JournalNeurosci Lett
PubMed ID9406866
Chloride (Cl-) current in the olfactory cell has been proposed to be excitatory and amplifying the receptor current. As an intracellular concentration of Cl- ([Cl-]i) is critically important for the proposed function, we tried to measure [Cl-]i of the isolated newt olfactory receptors using chloride-sensitive fluorescent dye, N-(6-methoxyquinolyl)-acetoethyl ester (MQAE). ... More
Amplification of CD95 activation by caspase 8-induced endosomal acidification in rat hepatocytes.
AuthorsReinehr R, Sommerfeld A, Keitel V, Grether-Beck S, Haüssinger D,
JournalJ Biol Chem
PubMed ID18045865
Although in rat hepatocytes CD95 is predominantly located inside the cell with almost undetectable immunostaining at the plasma membrane, the addition of CD95-ligand (CD95L) induces hepatocyte apoptosis, which is preceded by a targeting and activation of intracellularly localized CD95 to the plasma membrane including formation of the death-inducing signaling complex. ... More
ATP-induced P2X7-associated uptake of large molecules involves distinct mechanisms for cations and anions in macrophages.
AuthorsSchachter J, Motta AP, de Souza Zamorano A, da Silva-Souza HA, Guimarães MZ, Persechini PM,
JournalJ Cell Sci
PubMed ID18782864
Macrophages express the P2X(7) receptor and other nucleotide (P2) receptors, and display the phenomenon of extracellular ATP (ATP(e))-induced P2X(7)-dependent membrane permeabilization, which occurs through a poorly understood mechanism. We used patch-clamp recordings, cytoplasmic Ca(2+) measurements and fluorescent dye uptake assays to compare P2X(7)-associated transport phenomena of macrophages and HEK-293 cells ... More
Increased functional cell surface expression of CFTR and DeltaF508-CFTR by the anthracycline doxorubicin.
AuthorsMaitra R, Shaw CM, Stanton BA, Hamilton JW
JournalAm J Physiol Cell Physiol
PubMed ID11287314
Cystic fibrosis (CF) is a disease that is caused by mutations within the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The most common mutation, DeltaF508, accounts for 70% of all CF alleles and results in a protein that is defective in folding and trafficking to the cell surface. However, DeltaF508-CFTR ... More
S-Nitrosoglutathione induces functional DeltaF508-CFTR in airway epithelial cells.
AuthorsAndersson C, Gaston B, Roomans GM
JournalBiochem Biophys Res Commun
PubMed ID12270130
S-Nitrosoglutathione (GSNO) is an endogenous bronchodilator levels of which are reduced in the airways of cystic fibrosis (CF) patients. GSNO has recently been shown to increase maturation of CFTR in CF cell lines at physiological concentrations. The ability of S-nitrosoglutathione to direct the DeltaF508-CFTR to the plasma membrane and restore ... More
Fluorescent imaging of Cl- in Amphiuma red blood cells: how the nuclear exclusion of Cl- affects the plasma membrane potential.
AuthorsHoffman JF, Geibel JP
JournalProc Natl Acad Sci U S A
PubMed ID15637151
In this work, we test the idea that most, if not all, cellular Cl- of Amphiuma red blood cells is contained in the cytoplasm. If true, this could resolve the difference between the measured plasma membrane potential (Em) and that expected from the Donnan equilibrium distribution of Cl-. We studied ... More
Effects of hyperthermia on intracellular chloride.
AuthorsAmorino GP, Fox MH
JournalJ Membr Biol
PubMed ID8672083
Hyperthermia induces transient changes in [Na+]i and [K+]i in mammalian cells. Since Cl- flux is coupled with Na+ and K+ in several processes, including cell volume control, we have measured the effects of heat on [Cl-]i using the chloride indicator, MQAE, with flow cytometry. The mean basal level of [Cl-]i ... More
Normotonic cell shrinkage because of disordered volume regulation is an early prerequisite to apoptosis.
AuthorsMaeno E, Ishizaki Y, Kanaseki T, Hazama A, Okada Y
JournalProc Natl Acad Sci U S A
PubMed ID10900263
A major hallmark of apoptosis is normotonic shrinkage of cells. Here, we studied the relation between apoptotic cell shrinkage and apoptotic cell death. Induction of the apoptotic volume decrease (AVD) under normotonic conditions was found to be coupled to facilitation of the regulatory volume decrease (RVD), which is known to ... More
Microfluorometric analysis of Cl- permeability and its relation to oscillatory Ca2+ signalling in glucose-stimulated pancreatic beta-cells.
AuthorsEberhardson M, Patterson S, Grapengiesser E
JournalCell Signal
PubMed ID11152964
The cytoplasmic concentrations of Cl-([Cl-]i) and Ca2+ ([Ca2+]i) were measured with the fluorescent indicators N-(ethoxycarbonylmethyl)-6-methoxyquinilinum bromide (MQAE) and fura-2 in pancreatic beta-cells isolated from ob/ob mice. Steady-state [Cl-]i in unstimulated beta-cells was 34 mM, which is higher than expected from a passive distribution. Increase of the glucose concentration from 3 ... More
Ca(2+)-activated Cl- currents in pulmonary arterial myocytes.
AuthorsClapp LH, Turner JL, Kozlowski RZ
JournalAm J Physiol
PubMed ID8928862
Currents from smooth muscle cells isolated from the pulmonary arterial tree of the rat were recorded under voltage clamp using the whole cell configuration of the patch-clamp technique. Rapid increases in cytosolic free calcium evoked by flash photolysis of Nitr-5 activated a current that, following ion substitution and pharmacological experiments, ... More
Polarization of specific tropomyosin isoforms in gastrointestinal epithelial cells and their impact on CFTR at the apical surface.
AuthorsDalby-Payne JR, O'Loughlin EV, Gunning P
JournalMol Biol Cell
PubMed ID12960432
Microfilaments have been reported to be polarized in a number of cell types based both on function and isoform composition. There is evidence that microfilaments are involved in the movement of vesicles and the polarized delivery of proteins to specialized membrane domains. We have investigated the composition of actin microfilaments ... More
Chloride accumulation in mammalian olfactory sensory neurons.
AuthorsKaneko H, Putzier I, Frings S, Kaupp UB, Gensch T
JournalJ Neurosci
PubMed ID15356206
The generation of an excitatory receptor current in mammalian olfactory sensory neurons (OSNs) involves the sequential activation of two distinct types of ion channels: cAMP-gated Ca(2+)-permeable cation channels and Ca(2+)-gated Cl(-) channels, which conduct a depolarizing Cl(-) efflux. This unusual transduction mechanism requires an outward-directed driving force for Cl(-), established ... More
A microplate assay measuring chloride ion channel activity.
AuthorsWest MR, Molloy CR
JournalAnal Biochem
PubMed ID8921165
A microplate chloride ion channel assay, using N-(6-methoxyquinolyl) acetoethyl ester (MQAE) fluorescence changes has been developed. Forskolin stimulation of T84 cells caused cAMP-dependent, increased Cl- loss. Forskolin responses after 6 min gave an EC50 of 0.27 +/- 0.05 microM, illustrating the reproducibility of the assay. Forskolin exposure of CFPAC-1 cells, ... More
Clostridium perfringens epsilon toxin induces a rapid change of cell membrane permeability to ions and forms channels in artificial lipid bilayers.
AuthorsPetit L, Maier E, Gibert M, Popoff MR, Benz R
JournalJ Biol Chem
PubMed ID11278669
Epsilon toxin is a potent toxin produced by Clostridium perfringens types B and D, which are responsible for a rapidly fatal enterotoxemia in animals. One of the main properties of epsilon toxin is the production of edema. We have previously found that epsilon toxin causes a rapid swelling of Madin-Darby ... More
Characteristics and physiological role of the Ca(2+)-activated Cl- conductance in smooth muscle.
AuthorsLarge WA, Wang Q
JournalAm J Physiol
PubMed ID8769982
In this review we discuss the properties of the Ca(2+)-activated Cl- current [ICl(Ca)] recorded in isolated smooth muscle cells with electrophysiological techniques and speculate on the possible physiological role(s) of ICl(Ca) in smooth muscle function. In particular, we concentrate on 1) the Ca2+ dependence of ICl(Ca), 2) the mechanisms that ... More
Use of MQAE for measurement of intracellular [Cl-] in cultured aortic smooth muscle cells.
AuthorsKoncz C, Daugirdas JT
JournalAm J Physiol
PubMed ID7810712
A novel fluorescent indicator, N-[ethoxycarbonylmethyl]-6-methoxy-quinolinium bromide (MQAE), was used to measure intracellular chloride concentration ([Cl-]i) in primary cultures of rat aortic smooth muscle cells (VSMC). The hydrolytic and fluorescent properties of the dye were characterized. The intracellular Stern-Volmer constant was calculated to be 25 M-1. Cl- efflux curves were characteristic ... More
Reciprocal protein kinase A regulatory interactions between cystic fibrosis transmembrane conductance regulator and Na+/H+ exchanger isoform 3 in a renal polarized epithelial cell model.
AuthorsBagorda A, Guerra L, Di Sole F, Hemle-Kolb C, Cardone RA, Fanelli T, Reshkin SJ, Gisler SM, Murer H, Casavola V
JournalJ Biol Chem
PubMed ID11937500
Although Cystic fibrosis transmembrane conductance regulator (CFTR) has been shown to regulate the activity of NHE3, the potential reciprocal interaction of NHE3 to modulate the protein kinase A (PKA)-dependent regulation of CFTR in epithelial cells is still unknown. In the present work, we describe experiments to define the interactions between ... More
Role of intrahelical arginine residues in functional properties of uncoupling protein (UCP1).
AuthorsEchtay KS, Bienengraeber M, Klingenberg M
JournalBiochemistry
PubMed ID11318647
The functional role of the four intrahelical arginines in uncoupling protein (UCP1) from brown adipose tissue were studied in mutants where they were replaced by noncharged residues. Wild-type and mutant UCP1 were expressed in Saccharomyces cerevisiae. As measured in isolated UCP1, nucleotide binding was largely lost in mutants of R83, ... More
Measurement of changes in cell volume based on fluorescence quenching.
AuthorsSrinivas SP, Bonanno JA
JournalAm J Physiol
PubMed ID9142868
The intracellular fluorescence of 6-methoxy-N-(3-sulfopropyl)-quinolinium (SPQ), a Cl(-) -sensitive fluorescent dye, is quenched by intracellular organic anions and proteins of unknown identity. The concentration of these intracellular quenchers (ICQs), however, is dependent on cell volume. In the absence of Cl-, changes in the observed SPQ fluorescence may therefore reflect changes ... More
Chloride-dependent calcium transients induced by angiotensin II in vascular smooth muscle cells.
AuthorsMa YH, Wei HW, Su KH, Ives HE, Morris RC
JournalAm J Physiol Cell Physiol
PubMed ID14660489
Cl- is essential for the vasoconstrictive response to angiotensin II (ANG II). In vascular smooth muscle cells (VSMC), we determined whether ANG II-induced transient increase in intracellular Ca2+ concentration ([Ca2+]i) is Cl- dependent. After incubating the cells at different extracellular Cl- concentration ([Cl-]e) for 40 min, the ANG II-induced Ca2+ ... More
Coordinated regulation of gastric chloride secretion with both acid and alkali secretion.
Gastric secretion of hydrochloric acid requires protons and chloride, yet the mechanisms and regulation of gastric chloride secretion remain unclear. We developed an in vivo technique to simultaneously measure acid/base and chloride secretion into the gastric lumen of anesthetized rats. The cannulated stomach lumen was perfused with weakly pH-buffered chloride-free ... More
Differences in Ca(2+) signaling underlie age-specific effects of secretagogues on colonic Cl(-) transport.
AuthorsVenkatasubramanian J, Selvaraj N, Carlos M, Skaluba S, Rasenick MM, Rao MC
JournalAm J Physiol Cell Physiol
PubMed ID11171585
Taurodeoxycholic acid (TDC) stimulates Cl(-) transport in adult (AD), but not weanling (WN) and newborn (NB), rabbit colonic epithelial cells (colonocytes). The present study demonstrates that stimuli like neurotensin (NT) are also age specific and identifies the age-dependent signaling step. Bile acid actions are segment and bile acid specific. Thus ... More
Apical membrane sodium and chloride entry during osmotic swelling of renal (A6) epithelial cells.
AuthorsCrowe WE, Ehrenfeld J, Brochiero E, Wills NK
JournalJ Membr Biol
PubMed ID7541082
To assess the role of chloride in cell volume and sodium transport regulation, we measured cell height changes (CH), transepithelial chloride and sodium fluxes, and intracellular chloride content during challenge with hyposmotic solutions under open circuit (OC) conditions. CH maximally increased following hyposmotic challenge within approximately 5 minutes. The change ... More
Intracellular Cl- concentration in striated intralobular ducts from rabbit mandibular salivary glands.
AuthorsLau KR, Evans RL, Case RM
JournalPflugers Arch
PubMed ID8058473
Intralobular striated ducts have been isolated from rabbit mandibular salivary glands and maintained in primary culture for up to 2 days. Such ducts were loaded with the Cl(-)-sensitive fluorescent dye N-(ethoxycarbonylmethyl)-(6-methoxyquinolinium bromide) (MQAE) and intracellular Cl- concentration ([Cl-]i) monitored using a fluorescence microscope. Intracellular Cl- could be rapidly and reversibly ... More
Involvement of myosin light-chain kinase in chloride-sensitive Ca2+ influx in porcine aortic endothelial cells.
AuthorsTran QK, Watanabe H, Zhang XX, Takahashi R, Ohno R
JournalCardiovasc Res
PubMed ID10690296
OBJECTIVES: This study was designed to investigate the involvement of myosin light-chain kinase (MLCK) in bradykinin- and thapsigargin-induced changes in intracellular Cl- and Ca2+ concentrations ([Cl-]i; [Ca2+]i) in porcine aortic endothelial cells. METHODS: Using the fluorescent probes N-ethoxycarbonylmethyl-6-methoxyquinolinium bromide (MQAE) and fura-2/AM, the effects of different MLCK inhibitors on bradykinin- ... More
Regulation of pH in rat brain synaptosomes. II. Role of Cl-.
AuthorsMartínez-Zaguilán R, Gillies RJ, Sánchez-Armass S
JournalJ Neurophysiol
PubMed ID7931514
1. We have previously shown that rat brain synaptosomes exhibit a very dynamic Na+/H+ exchanger. We have also observed that although synaptosomes lack HCO3(-)-based transport mechanisms, they do respond with changes in pHi upon Clo- removal. 2. Here we show that when synaptosomes are transferred from Ringer solution (RS) to ... More
Calcium regulated chloride permeabilities in primary cultures of rabbit colonocytes.
AuthorsSahi J, Wiggins MP, Gibori GB, Layden TJ, Rao MC
JournalJ Cell Physiol
PubMed ID8707863
To determine if calcium-dependent secretagogues directly act on epithelial cells to elicit Cl- secretion, their effects on Cl- transport and intracellular Ca(2+) concentrations ([Ca2+]i) were determined in primary cultures of rabbit distal colonic crypt cells. The Cl- sensitive fluorescent probe, 6-methoxyquinolyl acetoethyl ester, MQAE and the Ca(2+)-sensitive fluorescent probe, fura-2AM ... More
Functional comparison of mouse slc26a6 anion exchanger with human SLC26A6 polypeptide variants: differences in anion selectivity, regulation, and electrogenicity.
The unusually low 78% amino acid identity between the orthologous human SLC26A6 and mouse slc26a6 polypeptides prompted systematic comparison of their anion transport functions in Xenopus oocytes. Multiple human SLC26A6 variant polypeptides were also functionally compared. Transport was studied as unidirectional fluxes of (36)Cl(-), [(14)C]oxalate, and [(35)S]sulfate; as net fluxes ... More
In the previous sections we demonstrated imaging of intracellular Ca2+ using our approach to FLIM. What other analytes can be imaged using FLIM? We have now characterized the lifetime of a good number of ion indicators. Based on these studies we know that Cl- can be imaged using FLIM with ... More
Control of apical membrane chloride permeability in the renal A6 cell line by nucleotides.
AuthorsBanderali U, Brochiero E, Lindenthal S, Raschi C, Bogliolo S, Ehrenfeld J
JournalJ Physiol
PubMed ID10457087
1. The effect of extracellular nucleotides applied on the apical side of polarised A6 cells grown on permeant filters was investigated by measuring the changes in (i) the 36Cl efflux through the apical membranes, (ii) the intracellular chloride concentrations (aCli, measured with N-(6-methoxyquinolyl) acetoethyl ester, MQAE), (iii) ICl, the short-circuit ... More
Basolateral membrane chloride permeability of A6 cells: implication in cell volume regulation.
AuthorsBrochiero E, Banderali U, Lindenthal S, Raschi C, Ehrenfeld J
JournalPflugers Arch
PubMed ID8584416
The permeability to Cl- of the basolateral membrane (blm) was investigated in renal (A6) epithelial cells, assessing their role in transepithelial ion transport under steady-state conditions (isoosmotic) and following a hypoosmotic shock (i.e. in a regulatory volume decrease, RVD). Three different complementary studies were made by measuring: (1) the Cl- ... More
Cell volume response to hyposmotic shock and elevated cAMP in bovine trabecular meshwork cells.
AuthorsSrinivas SP, Maertens C, Goon LH, Goon L, Satpathy M, Yue BY, Droogmans G, Nilius B
JournalExp Eye Res
PubMed ID14667824
PURPOSE: Hyposmolar perfusion of intact trabecular meshwork (TM) induces a decrease in its hydraulic conductivity (Lp). However, exposure to agents that elevate intracellular cAMP in TM cells increases Lp. Since volume of TM cells could directly influence porosity of the TM and hence Lp, this study has investigated changes in ... More
H+ transport by uncoupling protein (UCP-1) is dependent on a histidine pair, absent in UCP-2 and UCP-3.
AuthorsBienengraeber M, Echtay KS, Klingenberg M
JournalBiochemistry
PubMed ID9453747
UCP from brown adipose tissue of hamster (now UCP-1) expressed in Saccharomyces cerevisiae was used to examine the role of a conspicuous histidine pair H145 and H147 which is conserved among UCP-1 from various animals. Single and double mutants were generated by converting H145 and H147 into neutral residues (H145Q ... More
Hemolysis of erythrocytes by granulysin-derived peptides but not by granulysin.
AuthorsLi Q, Dong C, Deng A, Katsumata M, Nakadai A, Kawada T, Okada S, Clayberger C, Krensky AM
JournalAntimicrob Agents Chemother
PubMed ID15616319
Granulysin, a 9-kDa protein localized in human cytolytic T lymphoctyes and natural killer cell granules, is cytolytic against tumors and microbes but not against red blood cells. Synthetic peptides corresponding to the central region of granulysin recapitulate the lytic activity of the intact molecule, and some peptides cause hemolysis of ... More
Topiramate enhances GABA-mediated chloride flux and GABA-evoked chloride currents in murine brain neurons and increases seizure threshold.
AuthorsWhite HS, Brown SD, Woodhead JH, Skeen GA, Wolf HH
JournalEpilepsy Res
PubMed ID9332882
The anticonvulsant topiramate is effective in laboratory animals against maximal electroshock seizures, amygdala kindling, and spike-wave discharges and has demonstrated efficacy in humans for the treatment of complex partial seizures. However, its mechanism of action has yet to be clearly elucidated. When the chloride-sensitive fluorescent probe N-(ethoxycarbonylmethyl)-6-methoxyquinolinium bromide (MQAE) was ... More
Human trabecular meshwork cell volume regulation.
AuthorsMitchell CH, Fleischhauer JC, Stamer WD, Peterson-Yantorno K, Civan MM
JournalAm J Physiol Cell Physiol
PubMed ID12055101
The volume of certain subpopulations of trabecular meshwork (TM) cells may modify outflow resistance of aqueous humor, thereby altering intraocular pressure. This study examines the contribution that Na+/H+, Cl-/HCO exchange, and K+-Cl- efflux mechanisms have on the volume of TM cells. Volume, Cl- currents, and intracellular Ca2+ activity of cultured ... More
Janus kinase 2 (JAK2) regulates prolactin-mediated chloride transport in mouse mammary epithelial cells through tyrosine phosphorylation of Na+-K+-2Cl- cotransporter.
AuthorsSelvaraj NG, Omi E, Gibori G, Rao MC
JournalMol Endocrinol
PubMed ID11117534
Epithelial chloride (Cl-) transport is achieved by the coordinated action of symporters such as the Na+-K+-2Cl- cotransporter (NKCC1) and chloride channels such as the cystic fibrosis transmembrane conductance regulator (CFTR). As a secretory tissue, mammary epithelial cells are obvious candidates for such mechanisms, but Cl- transport and its hormonal regulation ... More
Long-wavelength iodide-sensitive fluorescent indicators for measurement of functional CFTR expression in cells.
AuthorsJayaraman S, Teitler L, Skalski B, Verkman AS
JournalAm J Physiol
PubMed ID10564094
Limitations of available indicators [such as 6-methoxy-N-(3-sulfopropyl)quinolinium (SPQ)] for measurement of intracellular Cl(-) are their relatively dim fluorescence and need for ultraviolet excitation. A series of long-wavelength polar fluorophores was screened to identify compounds with Cl(-) and/or I(-) sensitivity, bright fluorescence, low toxicity, uniform loading of cytoplasm with minimal leakage, ... More
Mutagenesis of the uncoupling protein of brown adipose tissue. Neutralization Of E190 largely abolishes pH control of nucleotide binding.
AuthorsEchtay KS, Bienengraeber M, Klingenberg M
JournalBiochemistry
PubMed ID9204870
For expression in Saccharomyces cerevisiae the cDNA of the uncoupling protein (UCP) of brown adipose tissue from hamster has been isolated and used to transform yeast cells. Optimized expression conditions yielded 2% of mitochondrial protein as UCP. UCP was isolated, avoiding copurification of ADP/ATP carrier and porin. Intrahelical E190, previously ... More
Cystic fibrosis transmembrane conductance regulator (CFTR) activity in nasal epithelial cells from cystic fibrosis patients with severe genotypes.
AuthorsAndersson C, Dragomir A, Hjelte L, Roomans GM
JournalClin Sci (Lond)
PubMed ID12241542
Cystic fibrosis is a heterogenic disease, in which the phenotype can also vary for patients with the same genotype. In the present study the function of the cystic fibrosis transmembrane conductance regulator (CFTR) in nasal epithelial cells from 19 adult patients with cystic fibrosis was investigated. All patients had severe ... More
Reconstitution of purified GABAA receptors: ligand binding and chloride transporting properties.
AuthorsDunn SM, Thuynsma RP
JournalBiochemistry
PubMed ID8292603
GABAA receptors have been solubilized from bovine brain membranes and, following purification by benzodiazepine affinity chromatography, have been reconstituted into phospholipid vesicles. Reconstituted vesicles were about 120 nm in diameter, and, on average, each vesicle contained fewer than one GABAA receptor which was reconstituted in an outside-out orientation. These preparations ... More
Ca2+ activates cystic fibrosis transmembrane conductance regulator- and Cl- -dependent HCO3 transport in pancreatic duct cells.
AuthorsNamkung W, Lee JA, Ahn W, Han W, Kwon SW, Ahn DS, Kim KH, Lee MG
JournalJ Biol Chem
PubMed ID12409301
Pancreatic duct cells secrete bicarbonate-rich fluids, which are important for maintaining the patency of pancreatic ductal trees as well as intestinal digestive function. The bulk of bicarbonate secretion in the luminal membrane of duct cells is mediated by a Cl(-)-dependent mechanism (Cl(-)/HCO(3)(-) exchange), and we previously reported that the mechanism ... More
Expression and regulation of the Na+-K+-2Cl- cotransporter NKCC1 in the normal and CFTR-deficient murine colon.
AuthorsBachmann O, Wüchner K, Rossmann H, Leipziger J, Osikowska B, Colledge WH, Ratcliff R, Evans MJ, Gregor M, Seidler U
JournalJ Physiol
PubMed ID12692180
Defective regulation and/or reduced expression of the Na+-K+-2Cl- cotransporter NKCC1 may contribute to the severe secretory defect that is observed in cystic fibrosis, but data concerning the expression and function of NKCC1 in cystic fibrosis transmembrane conductance regulator (CFTR)-deficient cells are equivocal. We therefore investigated NKCC1 mRNA expression, Na+-K+-2Cl- cotransport ... More
Cystic fibrosis transmembrane conductance regulator regulates luminal Cl-/HCO3- exchange in mouse submandibular and pancreatic ducts.
AuthorsLee MG, Choi JY, Luo X, Strickland E, Thomas PJ, Muallem S
JournalJ Biol Chem
PubMed ID10329661
We have demonstrated previously the regulation of Cl-/HCO3- exchange activity by the cystic fibrosis transmembrane conductance regulator (CFTR) in model systems of cells stably or transiently transfected with CFTR (Lee, M. G., Wigley, W. C., Zeng, W., Noel, L. E., Marino, C. R., Thomas, P. J., and Muallem, S. (1999) ... More
Increased intracellular Cl- concentration promotes ongoing inflammation in airway epithelium.
Authors
JournalMucosal Immunol
PubMed ID29545647
Vitexin reduces epilepsy after hypoxic ischemia in the neonatal brain via inhibition of NKCC1.
Authors
JournalJ Neuroinflammation
PubMed ID29925377
The role of voltage-gated chloride channels in the epileptogenesis of temporal lobe epilepsy.
Authors
JournalEBioMedicine
PubMed ID34391093
Enhanced Activity by NKCC1 and Slc26a6 Mediates Acidic pH and Cl- Movement after Cardioplegia-Induced Arrest of db/db Diabetic Heart.
Authors
JournalMediators Inflamm
PubMed ID31582903
Consequences of CRISPR-Cas9-Mediated CFTR Knockout in Human Macrophages.
Authors
JournalFront Immunol
PubMed ID32973772
CLIC1 recruits PIP5K1A/C to induce cell-matrix adhesions for tumor metastasis.
Authors
JournalJ Clin Invest
PubMed ID33079727
Chloride sensing by WNK1 regulates NLRP3 inflammasome activation and pyroptosis.
Authors
JournalNat Commun
PubMed ID34315884
Chloride Influx of Anion Exchanger 2 Was Modulated by Calcium-Dependent Spinophilin in Submandibular Glands.
Authors
JournalFront Physiol
PubMed ID30072910
(R)-Roscovitine and CFTR modulators enhance killing of multi-drug resistant Burkholderia cenocepacia by cystic fibrosis macrophages.