Abstract
Na+-K+ cotransport in human erythrocytes from healthy subjects has been studied by means of 23Na-nuclear magnetic resonance (NMR) in the presence of the anionic paramagnetic shift reagent dysprosium (III) tripolyphosphate [Dy(PPP)2/7-]. The intra- and extracellular 23Na-NMR signals were well separated, giving values of 6 ± 1 mM for internal sodium concentration. Determination of the furosemide-sensitive Na+ efflux, in the presence of ouabain, was obtained by correlating the chemical shift variation of the external signal with changes in external Na+ concentration. For this purpose, calibration curves were generated. The values of the maximum efflux velocity (V(max); 0.29-1 mmol · h-1 · 1 cells-1) measured in 10 healthy adult male subjects were found to be within the range of values obtained by other authors. The NMR method proposed for the study of Na+-K+ cotransport is relatively simple and allows quick evaluation of cotransport V(max) values for a number of samples, being a good candidate for the study of this transport mechanism in the presence of different pathologies.
| Original language | English |
|---|---|
| Journal | American Journal of Physiology - Cell Physiology |
| Volume | 262 |
| Issue number | 5 31-5 |
| Publication status | Published - 1992 |
Keywords
- normal human erythrocytes
- ouabain-insensitive sodium effluxes
- sodium-potassium transport mechanisms
ASJC Scopus subject areas
- Cell Biology
- Clinical Biochemistry
- Physiology
- Medicine(all)