Kinetics and stoichiometry of Na-dependent Li transport in human red blood cells.
Open Access
- 1 August 1978
- journal article
- research article
- Published by Rockefeller University Press in The Journal of general physiology
- Vol. 72 (2), 249-265
- https://doi.org/10.1085/jgp.72.2.249
Abstract
This paper describes the kinetics and stoichiometry of a tightly coupled Na-Li exchange transport system in human red cells. The system is inhibited by phloretin and furosemide but not by ouabain. Li influx by this system increases and saturates with increasing concentrations of external Li and internal Na and is inhibited competitively by external Na. Comparable functions relate Li efflux and Na efflux to internal and external Li and Na concentrations. Analysis of these relations yields the following values for the ion concentrations required to half-maximally activate the transport system: internal Na and Li 9.0 and 0.5 mM, respectively, external Na and Li 25 and 1.5 mM, respectively. The system performs a 1:1 exchange of Na and Li moving in opposite directions across the red cell membrane. We found no evidence for a simultaneous transport of more than one Na and Li by the system. The maximum transport rate of Na-dependent Li transport varied between 0.1 and 0.37 mmol/(liter of cells X h) in the red cells of the five normal male subjects studied. No significant variations between individual subjects were observed for bicarbonate-stimulated Li transport and for the residual Li fluxes which occur in the absence of bicarbonate and in the presence of ouabain plus phloretin.Keywords
This publication has 8 references indexed in Scilit:
- Lithium transport pathways in human red blood cells.The Journal of general physiology, 1978
- Effects of bicarbonate on lithium transport in human red cells.The Journal of general physiology, 1978
- Abnormal lithium and sodium transport in erythrocytes of a manic patient and some members of his familyProceedings of the National Academy of Sciences, 1977
- Studies on the lithium transport across the red cell membranePflügers Archiv - European Journal of Physiology, 1977
- Studies on the lithium transport across the red cell membranePflügers Archiv - European Journal of Physiology, 1977
- Studies on the lithium transport across the red cell membranePflügers Archiv - European Journal of Physiology, 1977
- Studies on the lithium transport across the red cell membranePflügers Archiv - European Journal of Physiology, 1976
- Effects of Some Monovalent Anions on Fluxes of Na and K, and on Glucose Metabolism of Ouabain Treated Human Red CellsActa Physiologica Scandinavica, 1967