Ouabain inhibits the increase due to palytoxin of cation permeability of erythrocytes
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Palytoxin in concentrations as low as 1 pM raises the potassium permeability of rat, human and sheep erythrocytes, and the sodium permeability of human erythrocytes. The release of potassium or sodium from human cells also occurs when extracellular sodium is replaced by choline.
Ouabain inhibits the release due to palytoxin of potassium ions from human, sheep and rat erythrocytes, and also the release of sodium ions from human cells. The glycoside effect is specific since a) it is already prominent with 5×10−8 M ouabain b) rat erythrocytes are less sensitive than human cells to ouabain c) potassium release due to amphotericin B or the Ca2+ ionophore A23187 is not influenced by ouabain and d) dog erythrocytes are resistant to palytoxin as well as to ouabain.
Palytoxin has no direct influence on the Na+, K+-ATPase. It inhibits the binding of [3H]ouabain to erythrocyte membranes within the same concentration range as unlabelled ouabain. It partially displaces bound [3H]ouabain, and partially inhibits the inactivation of erythrocyte ATPase by the glycoside. Depletion of ATP or of external Ca2+ renders the cells less sensitive to palytoxin. Nevertheless inhibition by ouabain can be still demonstrated with human cells whose ATP stores had been largely exhausted, and also in the absence of external Ca2+.
Palytoxin decreases the surface tension at the air-water interface.
We assume that the formation of nonspecific pores by palytoxin is linked with its surface activity. Further experiments should demonstrate whether ouabain prevents the binding of palytoxin to erythrocytes (“receptor hypothesis”), or whether an ouabain-sensitive hydrolysis of trace amounts of ATP (“metabolic hypothesis”) promotes the palytoxin effect.
Key wordsPalytoxin Ouabain Erythrocytes Permeability ATPase
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- Beaugé CA, del Campillo E (1976) The ATP dependence of a ouabain-sensitive sodium efflux activated by external sodium, potassium and lithium in human red cells. Biochim Biophys Acta 433:547–554Google Scholar
- Bernstein RE (1954) Potassium and sodium balance in mammalian red cells. Science 120:459–460Google Scholar
- Chan PC, Calabrese V, Theil LS (1964) Species differences in the effect of sodium and potassium ions on the ATPase of erythrocyte membranes. Biochim Biophys Acta 79:424–426Google Scholar
- Chhatwal GS, Ahnert-Hilger G, Beress L, Habermann E (1982) Palytoxin both induces and inhibits the release of histamine from rat mast cells. Int Archs Allergy Appl Immun 68:97–100Google Scholar
- Dodge JT, Mitchell C, Hanahan DJ (1963) The preparation and chemical characteristics of hemoglobin-free ghosts of human erythrocytes. Arch Biochem 100:119–130Google Scholar
- Eisner DA, Richards DE (1981) The interaction of potassium ions and ATP on the sodium pump of resealed red cell ghosts. J Physiol 319:403–418Google Scholar
- Erdmann E, Hasse W (1975) Quantitative aspects of ouabain binding to human erythrocyte and cardiae membranes. J Physiol 251:671–682Google Scholar
- Erdmann E, Schoner W (1973) Ouabain-receptor interactions in (Na+ +K+)-ATPase preparation from different tissues and species. Determination of kinetic constants and dissociation constants. Biochim Biophys Acta 307:386–398Google Scholar
- Habermann E, Beress L (1979) Iodine labelling of sea anemone toxin II, and binding to normal and denervated diaphragm. Naunyn-Schmiedeberg's Arch Pharmacol 309:165–170Google Scholar
- Habermann E, Ahnert-Hilger G, Chhatwal GS, Beress L (1981a) Delayed haemolytic action of palytoxin. General characteristics. Biochim Biophys Acta 649:481–486Google Scholar
- Habermann E, Chhatwal GS, Hessler HJ (1981b) Palytoxin raises the nonspecific permeability of erythrocytes in an ouabain-sensitive manner. Naunyn-Schmiedeberg's Arch Pharmacol 317:P374Google Scholar
- Horwitt BN (1952) Determination of inorganic serum phosphate by means of stannous chloride. J Biol Chem 199:537–541Google Scholar
- Moore RE, Bartolini G (1981) Structure of palytoxin. J Am Chem Soc 103:2491–2494Google Scholar
- Moore RE, Scheuer PJ (1971) Palytoxin: A new marine toxin from a coelenterate. Science 172:495–498Google Scholar
- Ponder E (1948) Hemolysis and related phenomena. Grune and Stratton, New YorkGoogle Scholar
- Uemura D, Neda K, Hirata Y (1981) Further studies on palytoxin. Tetrahedron Lett 22:2781–2784Google Scholar
- Walz FG, Chan PC (1966) Adenosine triphosphate dependent retention of sodium ions by a sodium and potassium-activated adenosine triphosphate preparation from erythrocyte membranes. Arch Biochem 113:569–574Google Scholar
- Whittam R (1958) Potassium movements and ATP in human red cells. J Physiol (London) 140:479–497Google Scholar