1
|
Smith GLN, Taylor RW. Synthesis and structures of three benzoannelated macrobicyclic diamides. ACTA CRYSTALLOGRAPHICA SECTION C STRUCTURAL CHEMISTRY 2022; 78:176-180. [DOI: 10.1107/s2053229622001449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 02/06/2022] [Indexed: 11/10/2022]
Abstract
We report the synthesis and structures of 9,10,20,21-tetrahydro-5,14-(ethanooxyethano)dibenzo[e,q][1,4,10,13,7,16]tetraoxadiazacyclooctadecine-6,13-dione [systematic name: 8,11,21,24,29-pentaoxa-1,18-diazatetracyclo[16.8.5.02,7.012,17]hentriaconta-2,4,6,12(17),13,15-hexaene-19,26-dione C24H28N2O8, I], 6,7,9,10,12,13,20,21-octahydro-5,14-(ethanooxyethano)dibenzo[e,q][1,4,10,13,7,16]tetraoxadiazacyclooctadecine-23,27-dione (8,11,21,24,29-pentaoxa-1,18-diazatetracyclo[16.8.5.02,7.012,17]hentriaconta-2,4,6,12,14,16-hexaene-27,31-dione; C24H28N2O7, II), and 9,10,20,21-tetrahydro-5,14-(ethanooxyethanooxyethano)dibenzo[e,q][1,4,10,13,7,16]tetraoxadiazacyclooctadecine-6,13-dione [8,11,21,24,29,32-hexaoxa-1,18-diazatetracyclo[16.8.8.02,7.012,17]tetratriaconta-2,4,6,12(17),13,15-hexaene-19,26-dione; C26H32N2O7, III]. All three compounds are made up of two tertiary diamides and are composed of two 15-membered rings with N2O3 donor sets and one 18-membered ring with an N2O4 donor set (compounds I and II) or three 18-membered rings with N2O4 donor sets (compound III). The solid-state structures of compounds I and II show little effects from the movement of the amide groups. However, compound III has a larger cavity and a different orientation of donor atoms in comparison to compounds I and II.
Collapse
|
2
|
Lutz NW, Bernard M. A method for multiparametric statistical quantification of the heterogeneity of free Na + concentration by 19 F MR spectroscopy: Proof of principle in silico and in vitro. NMR IN BIOMEDICINE 2019; 32:e4117. [PMID: 31297903 DOI: 10.1002/nbm.4117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 04/01/2019] [Accepted: 04/23/2019] [Indexed: 06/10/2023]
Abstract
Sodium(I) (Na+ ) is one of the most important cations in mammalian tissues. Since Na+ plays a key role in basic cell function, noninvasive methods for measuring intracellular concentrations of free sodium ions in biological tissue have been developed on the basis of 19 F NMR spectroscopy. However, intracellular Na+ levels are often not uniform throughout a tissue volume (or voxel) being measured. In such cases, [Na+ ] heterogeneity is not reflected in results obtained by the classical technique, and may even result in biased average values. For this reason, we have designed an approach for quantifying [Na+ ] heterogeneity. First, the 19 F MRS resonance from FCrown-1 serving as a "Na+ probe" is transformed into a [Na+ ] curve. Then the digital points of the resulting [Na+ ] profile are used to construct a histogram with specially developed algorithms. From each [Na+ ] histogram, at least eight quantitative parameters describing the underlying statistical [Na+ ] distribution were computed: weighted median, weighted mean, standard deviation, range, mode(s), kurtosis, skewness, and entropy. In addition to our new paradigm, we present a first validation based on (i) computer simulations and (ii) experimentally obtained 19 F MR spectra of model solutions. This basic proof of principle warrants future in vivo experiments, in particular because of its ability to provide quantitative information complementary to that made available by commonly used 23 Na MRI: (i) multiparametric statistical characterization of [Na+ ] distributions; (ii) total [Na+ ] heterogeneity analysis not intrinsically limited by the size of any MRI voxels; and (iii) analysis of unequivocally intracellular [Na+ ], as opposed to measurement of a combination of intra- and extracellular [Na+ ].
Collapse
Affiliation(s)
- Norbert W Lutz
- School of Medicine, CRMBM, Aix-Marseille University, Marseille, France
| | - Monique Bernard
- School of Medicine, CRMBM, Aix-Marseille University, Marseille, France
| |
Collapse
|
3
|
Affiliation(s)
- Zhenchuang Xu
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
| | - Chao Liu
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
| | - Shujuan Zhao
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
| | - Si Chen
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
| | - Yanchuan Zhao
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Ling-Ling Road, Shanghai 200032, China
| |
Collapse
|
4
|
Olaru AM, Robertson TBR, Lewis JS, Antony A, Iali W, Mewis RE, Duckett SB. Extending the Scope of 19F Hyperpolarization through Signal Amplification by Reversible Exchange in MRI and NMR Spectroscopy. ChemistryOpen 2017; 7:97-105. [PMID: 29318102 PMCID: PMC5754555 DOI: 10.1002/open.201700166] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Indexed: 01/21/2023] Open
Abstract
Fluorinated ligands have a variety of uses in chemistry and industry, but it is their medical applications as 18F-labelled positron emission tomography (PET) tracers where they are most visible. In this work, we illustrate the potential of using 19F-containing ligands as future magnetic resonance imaging (MRI) contrast agents and as probes in magnetic resonance spectroscopy studies by significantly increasing their magnetic resonance detectability through the signal amplification by reversible exchange (SABRE) hyperpolarization method. We achieve 19F SABRE polarization in a wide range of molecules, including those essential to medication, and analyze how their steric bulk, the substrate loading, polarization transfer field, pH, and rate of ligand exchange impact the efficiency of SABRE. We conclude by presenting 19F MRI results in phantoms, which demonstrate that many of these agents show great promise as future 19F MRI contrast agents for diagnostic investigations.
Collapse
Affiliation(s)
- Alexandra M Olaru
- Centre for Hyperpolarization in Magnetic Resonance, Department of Chemistry University of York Heslington YO10 5NY United Kingdom
| | - Thomas B R Robertson
- School of Science and the Environment, Division of Chemistry and Environmental Science Manchester Metropolitan University John Dalton Building, Chester St. Manchester M1 5GD United Kingdom
| | - Jennifer S Lewis
- Centre for Hyperpolarization in Magnetic Resonance, Department of Chemistry University of York Heslington YO10 5NY United Kingdom
| | - Alex Antony
- School of Science and the Environment, Division of Chemistry and Environmental Science Manchester Metropolitan University John Dalton Building, Chester St. Manchester M1 5GD United Kingdom
| | - Wissam Iali
- Centre for Hyperpolarization in Magnetic Resonance, Department of Chemistry University of York Heslington YO10 5NY United Kingdom
| | - Ryan E Mewis
- School of Science and the Environment, Division of Chemistry and Environmental Science Manchester Metropolitan University John Dalton Building, Chester St. Manchester M1 5GD United Kingdom
| | - Simon B Duckett
- Centre for Hyperpolarization in Magnetic Resonance, Department of Chemistry University of York Heslington YO10 5NY United Kingdom
| |
Collapse
|
5
|
Zhang C, Moonshi SS, Peng H, Puttick S, Reid J, Bernardi S, Searles DJ, Whittaker AK. Ion-Responsive 19F MRI Contrast Agents for the Detection of Cancer Cells. ACS Sens 2016. [DOI: 10.1021/acssensors.6b00216] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Cheng Zhang
- ARC
Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Shehzahdi Shebbrin Moonshi
- ARC
Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Hui Peng
- ARC
Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Simon Puttick
- ARC
Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Queensland, Brisbane, Queensland 4072, Australia
| | | | | | | | - Andrew K. Whittaker
- ARC
Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Queensland, Brisbane, Queensland 4072, Australia
| |
Collapse
|
6
|
Yu JX, Hallac RR, Chiguru S, Mason RP. New frontiers and developing applications in 19F NMR. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2013; 70:25-49. [PMID: 23540575 PMCID: PMC3613763 DOI: 10.1016/j.pnmrs.2012.10.001] [Citation(s) in RCA: 142] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Accepted: 10/23/2012] [Indexed: 05/06/2023]
Affiliation(s)
- Jian-Xin Yu
- Laboratory of Prognostic Radiology, Division of Advanced Radiological Sciences, Department of Radiology, UT Southwestern Medical Center, Dallas, Texas
| | - Rami R. Hallac
- Laboratory of Prognostic Radiology, Division of Advanced Radiological Sciences, Department of Radiology, UT Southwestern Medical Center, Dallas, Texas
| | - Srinivas Chiguru
- Laboratory of Prognostic Radiology, Division of Advanced Radiological Sciences, Department of Radiology, UT Southwestern Medical Center, Dallas, Texas
| | - Ralph P. Mason
- Laboratory of Prognostic Radiology, Division of Advanced Radiological Sciences, Department of Radiology, UT Southwestern Medical Center, Dallas, Texas
| |
Collapse
|
7
|
Jasanoff A. Contrast Agents for Magnetic Resonance Imaging. Cancer Imaging 2008. [DOI: 10.1016/b978-012374212-4.50011-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
8
|
Martin VV, Rothe A, Diwu Z, Gee KR. Fluorescent sodium ion indicators based on the 1,7-diaza-15-crown-5 system. Bioorg Med Chem Lett 2005; 14:5313-6. [PMID: 15454218 DOI: 10.1016/j.bmcl.2004.08.022] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2004] [Revised: 08/09/2004] [Accepted: 08/10/2004] [Indexed: 11/30/2022]
Abstract
A series of novel sodium ion-sensitive fluorescent reagents suitable for biological applications is described. The chelator nitrogen atom substituents affect the selectivity and affinity of cation binding, while the nature of the fluorophore determines the type of fluorescent response to metal ion chelation.
Collapse
Affiliation(s)
- Vladimir V Martin
- Molecular Probes, Inc., 29851 Willow Creek Road, Eugene, OR 97402, USA
| | | | | | | |
Collapse
|
9
|
Turner D, Stuenkel EL. Effects of depolarization evoked Na+ influx on intracellular Na+ concentration at neurosecretory nerve endings. Neuroscience 1998; 86:547-56. [PMID: 9881868 DOI: 10.1016/s0306-4522(98)00065-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Electrophysiological measurements of voltage-dependent Na+ influx using patch-clamp methodology were combined with optical monitoring of the free intracellular Na+ concentration in isolated rat neurohypophysial nerve endings to determine the relationship between Na+ influx generated by repetitive stimulation and change in [Na+]i. Application of step depolarizations under voltage-clamp-evoked tetrodotoxin-sensitive inward currents that were dependent upon extracellular Na+ and that exhibited rapid activation and inactivation properties. These characteristics substantiated the evoked current as a voltage-dependent Na+ current. Application of stimulus trains consisting of step depolarizations that mimick in frequency and duration those of action potentials were found to result in increases in [Na+]i. The induced change in [Na+]i was found to be related to the frequency and period of stimulation. Changes in [Na+]i were greatest at frequencies of 40 Hz and gave maximal changes with 30 s of continuous stimulation of approximately 2.4 mM. Sodium influx expressed as a molar quantity resulted in a nearly directly proportional increase in [Na+]i during the initial period of stimulation at low Na+ loads. When expressed as a charge density (pC/microm2) Na+ influx was found to increase with smaller diameter nerve endings as did the rate of change in [Na+]i in response to applied repetitive step depolarizations. Repetitive step depolarizations which simulate impulse activity that invade neuroendocrine nerve endings in vivo in response to physiological demand for hormone secretion resulted in an increased [Na+]i. It is postulated that this increased [Na+]i may provide a modulatory influence on the secretory response indirectly via alteration of intracellular calcium regulation or, perhaps, via a direct action on the secretory mechanism.
Collapse
Affiliation(s)
- D Turner
- Department of Physiology, University of Michigan Medical School, Ann Arbor 48109-0622, USA
| | | |
Collapse
|
10
|
Plenio H, Diodone R. Covalently Bonded Fluorine as a σ-Donor for Groups I and II Metal Ions in Partially Fluorinated Macrocycles. J Am Chem Soc 1996. [DOI: 10.1021/ja952928a] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Herbert Plenio
- Contribution from the Institut für Anorganische und Analytische Chemie, Albertstrasse 21, 79104 Freiburg, Germany
| | - Ralph Diodone
- Contribution from the Institut für Anorganische und Analytische Chemie, Albertstrasse 21, 79104 Freiburg, Germany
| |
Collapse
|
11
|
Gerber SH, Haunstetter A, Krüger C, Kaufmann A, Nobiling R, Haass M. Role of [Na+]i and [Ca2+]i in nicotine-induced norepinephrine release from bovine adrenal chromaffin cells. THE AMERICAN JOURNAL OF PHYSIOLOGY 1995; 269:C572-81. [PMID: 7573386 DOI: 10.1152/ajpcell.1995.269.3.c572] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Intracellular free sodium ([Na+]i) and calcium ([Ca2+]i) concentrations were determined by sodium-binding benzofuran isophthalate (SBFI) and fura 2 microfluorimetry, respectively, in bovine adrenal chromaffin cells (BCC). Validation of SBFI microfluorimetry by in vitro and in vivo calibration revealed a reliable assessment of [Na+]i within a range of 1-30 mM in single BCC. Nicotine (0.1-10 microM) induced concentration-dependent increases of both [Na+]i (from 3.3 +/- 0.1 to 25.6 +/- 0.4 mM, n = 76, P < 0.001) and [Ca2+]i (from 64 +/- 1 to 467 +/- 16 nM, n = 87, P < 0.001), which were accompanied by an increase in [3H]norepinephrine (NE) release. Consistent with an exocytotic release mechanism, nicotine-induced increments of [Ca2+]i and [3H]NE release were reduced under calcium-free conditions and by gadolinium chloride (40 microM), whereas [Na+]i was not affected. In contrast, a parallel attenuation of nicotine-evoked changes in [Na+]i, [Ca2+]i, and [3H]NE release was observed during reduction of the extracellular sodium concentration. The nicotine-evoked responses were neutralized by the nicotinic receptor antagonist hexamethonium (100 microM) but not by blockade of voltage-dependent sodium channels (1 microM tetrodotoxin). In conclusion, the nicotine-induced exocytotic release of [3H]NE is triggered by an increase in [Ca2+]i, which is facilitated by sodium influx through the nicotinic receptor ionophore.
Collapse
Affiliation(s)
- S H Gerber
- Department of Cardiology, University of Heidelberg, Germany
| | | | | | | | | | | |
Collapse
|
12
|
Plenio H, Diodone R. Komplexe partiell fluorierter Makrocyclen mit Metall-Fluor-??-Donorbindung und ihre Eignung als Metall-Ionen-Indikatoren. Angew Chem Int Ed Engl 1994. [DOI: 10.1002/ange.19941062111] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
13
|
Affiliation(s)
- R A Kauppinen
- Department of Biochemistry and Biotechnology, A.I. Virtanen Institute, University of Kuopio, Finland
| | | |
Collapse
|
14
|
Ivanics T, Blum H, Wroblewski K, Wang DJ, Osbakken M. Intracellular sodium in cardiomyocytes using 23Na nuclear magnetic resonance. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1221:133-44. [PMID: 8148390 DOI: 10.1016/0167-4889(94)90005-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Intracellular sodium content in superfused isolated rat cardiomyocytes was measured using 23Na nuclear magnetic resonance. The shift reagent dysprosium tripolyphosphate was added to the buffer to distinguish between NMR signals from the intracellular region and the extracellular buffer. The NMR visibility of the intracellular sodium signal was experimentally determined by measuring the changes induced in the sodium NMR signals by application of ischemia as an intervention. Intracellular volume was accounted for by determining the change in the sodium signal upon adding cells (in beads) to the buffer solution at the beginning of each experiment and by killing the cells (in beads) with Triton X-100 at the end of each experiment. The visibility of intracellular sodium (relative to extracellular) was 0.47 +/- 0.12 (mean +/- S.D., n = 12). The average intracellular sodium concentration using this visibility is 29 +/- 4.5 mM (n = 12). This value is much higher than results obtained by some investigators using NMR techniques and by others using different standard methods, with the exception of those methods which evaluate the total intracellular sodium (atomic absorption spectroscopy and X-ray microanalysis). We conclude that total Nai is higher than generally reported, using other accepted techniques such as ion-specific electrodes, and that 23Na-NMR analysis can be used to accurately determine Nai in intact cells.
Collapse
Affiliation(s)
- T Ivanics
- Department of Medicine (Cardiology), University of Pennsylvania School of Medicine, Philadelphia 19104
| | | | | | | | | |
Collapse
|
15
|
Plenio H, Burth D. 19F NMR indicator for protons and metal ions with direct fluorine–metal interactions. ACTA ACUST UNITED AC 1994. [DOI: 10.1039/c39940002297] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
16
|
Fluorinated macromolecular probes for non-invasive assessment of pH by Magnetic resonance spectroscopy. Bioorg Med Chem Lett 1993. [DOI: 10.1016/s0960-894x(01)80874-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
17
|
Ruiz-Cabello J, Cohen JS. NMR and the study of pathological state in cells and tissues. INTERNATIONAL REVIEW OF CYTOLOGY 1993; 145:1-63. [PMID: 8500979 DOI: 10.1016/s0074-7696(08)60424-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- J Ruiz-Cabello
- Department of Pharmacology, Georgetown University Medical School, Washington, D.C. 20007
| | | |
Collapse
|
18
|
Daniell LC. Determination of the intravesicular ionized sodium concentration in a cell-free brain membrane vesicle preparation using the fluorescent indicator, SBFI. Anal Biochem 1992; 202:239-44. [PMID: 1519747 DOI: 10.1016/0003-2697(92)90100-l] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The intravesicular ionized Na concentration (Nai) was measured using the fluorescent Na indicator, SBFI, in microsacs, a cell-free brain vesicle preparation. SBFI fluorescence was monitored by a dual excitation-wavelength method at the same wavelengths commonly employed for Fura-2 determination of intracellular ionized calcium concentrations (Cai). Calibration of SBFI fluorescence was reliably performed in brain microsacs in situ. Resting Nai was dependent on the extravesicular Na concentration (Nao) and was about 36 mM in the presence of 120 mM extracellular Nao. In the presence of ouabain, an inhibitor of the plasma membrane Na/K-ATPase, Nai increased by 27 mM over 60 s. Nai was also increased by resuspension of microsacs in buffers of low free Ca concentrations (0 to 0.8 mM), indicating that the extravesicular Ca concentration (Cao) is an important regulator of Nai. Alkaloids active at voltage-sensitive Na channels, veratridine and aconitine, also increased Nai. These results demonstrate the presence of homeostatic mechanisms for neuronal Nai regulation and show that Nai can be measured in a cell-free brain vesicle preparation using SBFI.
Collapse
Affiliation(s)
- L C Daniell
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta 30912-2300
| |
Collapse
|
19
|
|
20
|
Prior MJW, Maxwell RJ, Griffiths JR. Fluorine-19F NMR Spectroscopy and Imaging In-Vivo. ACTA ACUST UNITED AC 1992. [DOI: 10.1007/978-3-642-77218-4_4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
|
21
|
Sage SO, Rink TJ, Mahaut-Smith MP. Resting and ADP-evoked changes in cytosolic free sodium concentration in human platelets loaded with the indicator SBFI. J Physiol 1991; 441:559-73. [PMID: 1816386 PMCID: PMC1180214 DOI: 10.1113/jphysiol.1991.sp018767] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
1. Cytosolic free Na+ concentration, [Na+]i, was investigated in human platelets loaded with the fluorescent indicator SBFI (sodium-binding benzofuran isophthalate). 2. SBFI fluorescence from platelet suspensions was measured at excitation wavelengths of 340 and 385 nm and the 340/385 nm fluorescence ratio was calibrated in terms of [Na+]i in situ. [Na+]i was set to known values by resuspending cells in media with various [Na+], in the presence of the Na(+)-K+ ionophore, gramicidin. 3. Basal free [Na+]i was 5.5 +/- 0.3 mM (n = 50). This is considerably lower than estimates of total platelet Na+, suggesting that much intracellular Na+ is sequestered or bound. 4. ADP (40 microM) evoked a rise in [Na+]i from 6.4 +/- 0.7 to 18.3 +/- 1.1 mM (n = 8). The ADP-evoked rise in [Na+]i was abolished when external Na+ was replaced with N-methyl-D-glucamine. This indicates that the rise in [Na+]i was due to Na+ entry. 5. In platelets loaded with the fluorescent pH indicator, BCECF, 40 microM-ADP was shown to evoke a fall in cytosolic pH (pHi) from 7.21 +/- 0.03 to 7.12 +/- 0.03 (n = 10). Three minutes after ADP addition pHi had only recovered to 7.15 +/- 0.03. The recovery was dependent on external Na+, suggesting it was mediated by Na(+)-H+ exchange. However, this would only account for an increase in [Na+]i of approximately 0.5 mM, indicating most of the ADP-evoked Na+ entry occurred by other mechanisms. 6. Stopped-flow fluorimetry showed that the ADP-evoked rise in [Na+]i commenced without measurable delay and peaked within 1 s. The initial kinetics were thus similar to those reported for ADP-evoked rises in [Ca2+]i. 7. Cell-attached patch-clamp recordings showed that ADP evoked single-channel inward currents when included in the pipette-filling solution. The currents were similar whether Ca2+ was present or absent from the pipette. The slope conductance was 11 pS in the presence of external Ca2+ and 10 pS in its absence. Current-voltage relationships were similar and the reversal potentials were close to 0 mV under both conditions. 8. SK & F 96,365 (20 microM), a blocker of receptor-mediated Ca2+ entry in several non-excitable cells, blocked the ADP-evoked rise in [Na+]i. This compound has been shown to only partly block the biphasic ADP-evoked rise in [Ca2+]i, being selective for the fast, receptor-operated phase of entry. 9. These data suggest that ADP rapidly activates a channel in that platelet plasma membrane which is permeable to Na+ and divalent cations.
Collapse
Affiliation(s)
- S O Sage
- Physiological Laboratory, University of Cambridge
| | | | | |
Collapse
|
22
|
Lundberg P, Harmsen E, Ho C, Vogel HJ. Nuclear magnetic resonance studies of cellular metabolism. Anal Biochem 1990; 191:193-222. [PMID: 2085167 DOI: 10.1016/0003-2697(90)90210-z] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- P Lundberg
- Department of Biological Sciences, University of Calgary, Alberta, Canada
| | | | | | | |
Collapse
|
23
|
|
24
|
|
25
|
Harootunian AT, Kao JP, Eckert BK, Tsien RY. Fluorescence ratio imaging of cytosolic free Na+ in individual fibroblasts and lymphocytes. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(19)47322-5] [Citation(s) in RCA: 244] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
|
26
|
Malet-Martino MC, Martino R. The application of nuclear magnetic resonance spectroscopy to drug metabolism studies. Xenobiotica 1989; 19:583-607. [PMID: 2669361 DOI: 10.3109/00498258909042297] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
1. The applications of n.m.r. spectroscopy studies to drug metabolism, both in vitro (biofluids, isolated cells, excised tissue samples, isolated organs) and in vivo (animals, humans) are reviewed. 2. N.m.r. is a relatively insensitive technique, but it has the great advantage of being non-invasive and non-destructive, i.e. it allows a direct study of intact biological samples. 3. The majority of studies examined deal with 19F-n.m.r. spectroscopy mainly because of the favourable n.m.r. characteristics of this nucleus, and the low level of endogenous fluorine which gives no detectable 19F signal. However, the potential utility of 1H-31P- and 13C-n.m.r. is also emphasized.
Collapse
Affiliation(s)
- M C Malet-Martino
- Groupe de RMN Biomédicale, Laboratoire des IMRCP, Université Paul Sabatier, Toulouse, France
| | | |
Collapse
|
27
|
Affiliation(s)
- R Y Tsien
- Department of Physiology-Anatomy, University of California, Berkeley 94720
| |
Collapse
|
28
|
Civan MM, Shporer M. Chapter 1 Physical State of Cell Sodium. CURRENT TOPICS IN MEMBRANES AND TRANSPORT 1989. [DOI: 10.1016/s0070-2161(08)60005-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
29
|
Kirschenlohr HL, Metcalfe JC, Morris PG, Rodrigo GC, Smith GA. Ca2+ transient, Mg2+, and pH measurements in the cardiac cycle by 19F NMR. Proc Natl Acad Sci U S A 1988; 85:9017-21. [PMID: 3194404 PMCID: PMC282653 DOI: 10.1073/pnas.85.23.9017] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
19F NMR indicators have been used to measure the free cytosolic cation concentrations ([Mn+]i, where M is the atomic symbol and n is the value of the charge) of Ca2+, H+, and Mg2+ in perfused ferret hearts. The [Ca2+]i transient, cytosolic pH (pHi), and [Mg2+]i have also been followed at 16 phases in the cardiac cycle in hearts paced at 1.25 Hz at 30 degrees C. The initial [Ca2+]i rose rapidly after a 50-ms delay, was maximal at greater than 1.5 microM after 150 ms, and declined thereafter to the initial concentration. In contrast, no significant changes in pHi (pH 7.03 +/- 0.08) or [Mg2+]i (1.2 +/- 0.1 mM) were detected in the cycle. A decrease in developed pressure when the [Ca2+]i indicator (but not the pHi or [Mg2+]i indicator) was loaded into hearts was substantially reversed by the addition of 50 microM ZnCl2 to the perfusion medium. The Zn2+ was taken up into the myoplasm and displaced Ca2+ bound to the indicator, a symmetrically substituted difluoro derivative of 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (5FBAPTA), as evidenced by the appearance of the Zn-5FBAPTA resonance. The decrease in developed pressure caused by 5FBAPTA, therefore, may be due to its Ca2+ buffering effect on the myoplasm. By coloading hearts with the [Ca2+]i and pHi indicators, simultaneous measurement of several [Mn+]i was demonstrated, which should provide a useful addition to the methods available to monitor cardiac function and pharmacology.
Collapse
Affiliation(s)
- H L Kirschenlohr
- Department of Biochemistry, University of Cambridge, United Kingdom
| | | | | | | | | |
Collapse
|
30
|
Smith GA, Hesketh TR, Metcalfe JC. Design and properties of a fluorescent indicator of intracellular free Na+ concentration. Biochem J 1988; 250:227-32. [PMID: 3355514 PMCID: PMC1148837 DOI: 10.1042/bj2500227] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
We have recently described a cryptand structure, FCryp-1, with appropriate properties for an indicator of intracellular free Na+ concentration using the 19F-n.m.r. chemical shift of the incorporated 5FBAPTA [1,2-bis-(2-amino-5-fluorophenoxy)ethane-NNN'N'-tetra-acetic acid] reporter group to measure the free cytosolic Na+ concentration [( Na+]i) [Smith, Morris, Hesketh and Metcalfe (1986) Biochim. Biophys. Acta 889, 82-83]. FCryp-1 carries four carboxylate groups to confer aqueous solubility and the indicator is membrane-permeant when the carboxyls are esterified with acetoxymethyl ester groups. Here we describe the synthesis of FCryp-2 to provide a fluorescent indicator of [Na+]i. FCryp-2 retains the parent tribenzo (2:2:1) cryptand structure of FCryp-1, in which the benzenoid ring at C-21 in FCryp-1 is replaced by an indole derivative which acts as the fluorophor in FCryp-2. With excitation at 340 nm, FCryp-2 gives an emission maximum at 460 nm in the absence of Na+ which shifts to 395 nm when FCryp-2 is saturated with Na+, with an isosbestic point at 455 nm. The apparent dissociation constant of FCryp-2 in a buffer solution of 100 mM-KCl/20 mM-KH2PO4/K2HPO4, pH 7.0, at 37 degrees C is 6.0 mM and the free Na+ concentration can be measured either from the calibrated fluorescence intensity at 395 nm, which increases 25-fold when Na+ is bound to FCryp-2, or from the ratio of fluorescence intensities at 395 nm and 455 nm. The measurement of free [Na+] by either method is unaffected by K+, Ca2+ or Mg2+ in the normal intracellular concentration ranges. Free [Na+] measurements by the ratio method are unaffected by pH from 6.6 to 7.6.
Collapse
Affiliation(s)
- G A Smith
- Department of Biochemistry, University of Cambridge, U.K
| | | | | |
Collapse
|
31
|
Abstract
19F-nuclear magnetic resonance (NMR) has been used to determine both intracellular pH and oxygen concentrations in cell suspensions. Oxygen concentrations in Paracoccus denitrificans and insulinoma cells, RINm5F, in the NMR probe can be monitored directly by 1/T1 measurements of perfluorotripropylamine (FTPA)/lecithin emulsion added to the suspensions. With FTPA oxygen monitoring, we investigated the relative aeration capabilities of two types of NMR chambers. Both normal and transformed eucaryotic cells can be maintained in either chamber for at least 1-2 h at cytocrits of up to 20-25%, with 30% oxygen saturation and cell viabilities of 90-95%. Similar concentrations of procaryotes were maintained aerobic with high FTPA concentrations in the more efficient of the two NMR chambers. A new precursor molecule for the 19F-NMR pH indicator difluoromethylalanine, the para-chlorophenyl ester, has been tested and used in RINm5F cells and P. denitrificans, neither of which hydrolyzes methyl esters.
Collapse
Affiliation(s)
- J Taylor
- Department of Physiology, Univesity of Pennsylvania School of Medicine, Philadelphia 19104-6085
| | | |
Collapse
|