Erythrocyte Na+/K+ ATPase activity measured with sup 23 Na NMR

Journal Article · Wed Nov 01 00:00:00 EST 1989 · Magnetic Resonance in Medicine; (USA)

DOI:https://doi.org/10.1002/mrm.1910120203· OSTI ID:7192024

Ouwerkerk, R; van Echteld, C J; Staal, G E; Rijksen, G ^[1]

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1. University Hospital, Utrecht (Netherland)

A {sup 23}Na NMR assay for measurement of erythrocyte Na+/K+ ATPase activity is presented. Using the nonpermeant shift reagent dysprosium tripolyphosphate the signals of intra- and extracellular sodium are separated, enabling measurement of sodium fluxes nondestructively, without the need to physically separate the cells from their environment. By increasing membrane permeability with nystatin we have shown that the assay allows the detection of differences in membrane permeability. With low doses of nystatin the ouabain-sensitive sodium flux increased more than twofold. With high doses of nystatin the Na+/K+ pump could not prevent an almost total equilibration of intra- and extracellular sodium. All sodium that entered the cells remained NMR visible, proving that sodium influx can be measured quantitatively. {sup 31}P NMR spectra taken before and after the assay revealed a slight acidification of the cells and no significant change in ATP concentration. No evidence of Dy3+ entering the cell was observed.

• OSTI ID: 7192024
• Journal Information: Magnetic Resonance in Medicine; (USA), Vol. 12:2; ISSN 0740-3194
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ATP
ENZYME ACTIVITY
CELL MEMBRANES
PERMEABILITY
CHEMICAL SHIFT
ERYTHROCYTES
MAN
MEMBRANE TRANSPORT
NMR SPECTRA
NUCLEAR MAGNETIC RESONANCE
OUABAIN
PHOSPHORUS 31
POTASSIUM COMPOUNDS
SODIUM 23
SODIUM COMPOUNDS
ALKALI METAL COMPOUNDS
ALKALI METAL ISOTOPES
ANIMALS
BIOLOGICAL MATERIALS
BLOOD
BLOOD CELLS
BODY FLUIDS
CARBOHYDRATES
CARDIAC GLYCOSIDES
CARDIOTONICS
CARDIOVASCULAR AGENTS
CELL CONSTITUENTS
DRUGS
GLYCOSIDES
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
MAMMALS
MATERIALS
MEMBRANES
NUCLEI
NUCLEOTIDES
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
PHOSPHORUS ISOTOPES
PRIMATES
RESONANCE
SODIUM ISOTOPES
SPECTRA
STABLE ISOTOPES
STROPHANTHINS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques