[Mechanism of the antiarrhythmic effect of inorganic phosphates in digitalis poisoning].
THe synergistic effects between calcium and the therapeutic and toxic actions of the cardiac glycosides have suggested that a way of treating digitalis intoxication could be through a decrease in free plasma calcium. In 1966, Burckhardt and La-Due published a study based on the inverse relationship that exists between plasma phosphates and calcium. It was shown then that potassium phosphate had a pronounced antiarrhythmic effect on digitalis induced arrhythmias. The use of potassium phosphate for this study prevented the analysis of the role of the phosphates in these effects, since the actions of potassium in digitalis toxicity precluded any conclusion. The purpose of the present paper is to study the effect of phosphates on digitalis intoxication and its possible mechanism of action. The results obtained demonstrated: 1) Phosphates have a marked antiarrhythmic effect in digitalis induced arrhythmias. 2) This effect is due to a decrease in free plasma calcium. 3) The lowering of this calcium pool occurs in the blood and is not mediated by hormonal or renal mechanisms. 4) The ions that disappear from the free calcium pool do not precipitate. 5) The use of phosphates could be useful in the treatment of some clinical cases of advanced digitalis intoxication.
D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D001145:Arrhythmias, Cardiac / Q000188:drug therapy; D002130:Calcium Phosphates / Q000627:therapeutic use; D004071:Digitalis Glycosides / Q000506:poisoning*; D004285:Dogs; D004353:Drug Evaluation, Preclinical; D004357:Drug Synergism; D005260:Female; D066298:In Vitro Techniques; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D010710:Phosphates / Q000627:therapeutic use*; D010758:Phosphorus / Q000627:therapeutic use; D012964:Sodium / Q000627:therapeutic use
D000889:Anti-Arrhythmia Agents; D002130:Calcium Phosphates; D004071:Digitalis Glycosides; D010710:Phosphates; D010758:Phosphorus; D012964:Sodium
Mecanismo del efecto antiarrítmico de los fosfatos inorgánicos en la intoxicación digitálica.