An electronic mechanism in the action of drugs, ATP, transmitters and other cardinal adsorbents. II. Effect of ouabain on the relative affinities for Li+, Na+, K+, and Rb+ of surface anionic sites that mediate the entry of Cs+ into frog ovarian eggs.
Ouabain enhanced the inhibitory effects of Li+, Na+, and K+ on the rate of Cs+ permeation into frog ovarian eggs while it reduced the inhibiting effect of Rb+. The data agree with earlier demonstrated effects of ouabain on the rank order of selective accumulation of the five alkali-metals in frog muscles and on the relative effectiveness of glycine, Li+, Na+, K+, Rb+, and Cs+ in inhibiting the rate of entry of Cs+ into frog sartorius muscle. In all three cases, the ouabain behaved as an electron-donating cardinal adsorbent (EDC) causing a rise of the electron density (c-value) of the beta- and gamma-carboxyl groups in the cell cytoplasm (for selective accumulation) and on the cell surface (for selective ion permeation). Explanations based on the association-induction hypothesis were offered why an EDC like ouabain does not initiate cell activation (like veratridine does) and why Ca++ and tetradotoxin delays or inhibits physiological and artificial cell activation.
Ling
G N
GN
Molecular Biology Department, Pennsylvania Hospital, Philadelphia 19107.
Fu
Y Z
YZ
D000818:Animals; D002414:Cations, Monovalent; D002586:Cesium / Q000378:metabolism*; D005260:Female; D066298:In Vitro Techniques; D007700:Kinetics; D008094:Lithium / Q000494:pharmacology; D009865:Oocytes / Q000187:drug effects / Q000378:metabolism*; D010042:Ouabain / Q000494:pharmacology*; D011188:Potassium / Q000494:pharmacology; D011898:Ranidae; D012413:Rubidium / Q000494:pharmacology; D012964:Sodium / Q000494:pharmacology
D002414:Cations, Monovalent; D002586:Cesium; D010042:Ouabain; D008094:Lithium; D012964:Sodium; D012413:Rubidium; D011188:Potassium