Title: C-13-NMR studies of transmembrane electron transfer to extracellular ferricyanide in human erythrocytes
Authors: Himmelreich, Uwe
Kuchel, PW # ×
Issue Date: Jun-1997
Publisher: Published by Springer-Verlag on behalf of the Federation of European Biochemical Societies
Series Title: European Journal of Biochemistry vol:246 issue:3 pages:638-645
Abstract: Human erythrocytes are known to reduce ferricyanide (hexacyanoferrate) [Fe(CN)(6)](3-) to ferrocyanide [Fe(CN)(6)](2-) in an extracellular reaction that involves the transmembrane transfer of reducing equivalents: potentially these could be either electrons from NADH, formed in glycolysis inside the cells or transmembrane exchange of reduced solutes. The C-13-NMR resonance of [Fe((CN)-C-13)(6)](3-) (which was synthesised in our laboratory) was seen to be very broad while that of ferrocyanide was narrow. This phenomenon formed the basis of a simple non-invasive. procedure to study ferricyanide reduction in high-haematocrit suspensions of erythrocytes. The method should be directly applicable to other cell types In a series of experiments, erythrocyte metabolism was studied in the presence of ferricyanide, using H-1, C-13, and P-31 NMR spectroscopy. Incubating the cells with C-13-labelled glucose enabled the rate of ferricyanide reduction, glucose utilisation, and lactate and bicarbonate production to be measured simultaneously. Various metabolic states were imposed as follows: glycolysis was inhibited with F- and iodoacetate; glucose transport was inhibited with phloretin and cytochalasin B; and anion transport was inhibited with dinitrostilbene 2,2'-disulfonate and p-chloromercuriphenyl sulfonate. Earlier work was confirmed, showing that ascorbate is intimately involved in the reduction reaction; but its main action appears not to be mediated by membrane transport but in a membrane-associated redox-protein complex that is functionally linked to glycolysis. Also, large differences (factors of three) in the rate of the reduction reaction were recorded in erythrocytes from different, apparently healthy, donors.
ISSN: 0014-2956
Publication status: published
KU Leuven publication type: IT
Appears in Collections:Radiology
Biomedical MRI
× corresponding author
# (joint) last author

Files in This Item:

There are no files associated with this item.

Request a copy


All items in Lirias are protected by copyright, with all rights reserved.

© Web of science