Digitalis-like factors from human urine.
We isolated two candidates for endogenous digitalis-like factors from human urine based on the inhibition of [3H]ouabain binding to intact human erythrocytes. The more-polar ouabain-displacing compound-1 (ODC-1) closely resembled ouabain in biological, physicochemical, and chromatographic properties. Moreover, anti-ouabain IgG dose-dependently neutralized the action of ODC-1. The less-polar ODC-2 behaved identically to digoxin in three analytical high-performance liquid chromatography and thin layer chromatography systems. Fast atom bombardment mass spectrum and proton nuclear magnetic resonance spectrum supported the notion that ODC-2 may be indistinguishable from digoxin. The possibility that substances quite similar to cardenolides are synthesized in the mammalian body must be seriously considered.
Goto
A
A
Second Department of Internal Medicine, Faculty of Medicine, University of Tokyo, Japan.
Yamada
K
K
Yagi
N
N
Hui
C
C
Nagoshi
H
H
Sasabe
M
M
Yoshioka
M
M
D001665:Binding Sites; D001685:Biological Factors / Q000737:chemistry / Q000302:isolation & purification / Q000652:urine*; D001798:Blood Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000652:urine*; D002298:Cardenolides; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D004077:Digoxin; D004912:Erythrocytes / Q000378:metabolism; D006801:Humans; D007074:Immunoglobulin G / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D010042:Ouabain / Q000378:metabolism; D012503:Saponins; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors
D001685:Biological Factors; D001798:Blood Proteins; D002298:Cardenolides; D007074:Immunoglobulin G; D012503:Saponins; C034504:digoxin-like factors; D010042:Ouabain; D004077:Digoxin; D000254:Sodium-Potassium-Exchanging ATPase