Long‐term effect of ouabain and sodium pump inhibition on a neuronal membrane
- 1 October 1974
- journal article
- Published by Wiley in The Journal of Physiology
- Vol. 242 (1), 49-60
- https://doi.org/10.1113/jphysiol.1974.sp010693
Abstract
1. The long-term effects of ouabain on the membrane potential of the Anisodoris giant neurone (G cell) were examined in cells maintained for periods of up to 15 hr at 11-13 degrees C.2. In the presence of ouabain (5 x 10(-4)M), the membrane potential depolarized to a constant level for 1-4 hr, then hyperpolarized for 5-7 hr after which it gradually depolarized again.3. During the hyperpolarizing phase, after 6-8 hr in ouabain, [K](1) fell approximately 50%, [Na](1) increased 50-100% and the P(Na)/P(K) ratio decreased to 25% of its initial value.4. After 8 hr in ouabain the membrane conductance increased two- to fourfold. This increase was independent of temperature and membrane rectification.5. The K permeability (P(K)) was calculated from the constant field equation, and showed a fourfold increase after long-term treatment with ouabain. This rise in P(K) probably underlies the membrane hyperpolarization and the decrease in the P(Na)/P(K) ratio.6. It is suggested that inhibition of the Na(+) pump with ouabain causes a gradual rise in [Na](1) which secondarily leads to Ca(2+) uptake, an increase in [Ca](1), and thereby an increase in P(K).Keywords
This publication has 23 references indexed in Scilit:
- The effects of temperature and ions on the current—voltage relation and electrical characteristics of a molluscan neuroneThe Journal of Physiology, 1971
- Actions of dinitrophenol and some other metabolic inhibitors on cortical neuronesThe Journal of Physiology, 1971
- The control by internal calcium of membrane permeability to sodium and potassiumThe Journal of Physiology, 1971
- Temperature dependence of a sodium—potassium permeability ratio of a molluscan neuroneThe Journal of Physiology, 1970
- Contributions of the sodium pump and ionic gradients to the membrane potential of a molluscan neuroneThe Journal of Physiology, 1970
- Relation of Intracellular Ca2+ to Retention of K+ by Liver SlicesNature, 1970
- The ouabain‐sensitive fluxes of sodium and potassium in squid giant axonsThe Journal of Physiology, 1969
- The influence of calcium on sodium efflux in squid axonsThe Journal of Physiology, 1969
- Die Abhängigkeit der Ca++-Aufnahme isolierter Mitochondrien des Herzmuskels von der Na+-und K+-Konzentration als mögliche Ursache der inotropen DigitaliswirkungCellular and Molecular Life Sciences, 1967
- Energy‐Linked Ion Movements in Mitochondrial SystemsPublished by Wiley ,1967