The effect of PAF (platelet-activating factor) on experimental cardiac arrhythmias and its inhibition by substances influencing arachidonic acid metabolites.
Platelet-activating factor (PAF), 10(-11) mol decreased the threshold of ouabain induced arrhythmia in guinea-pigs. The thresholds inducing premature ventricular beats and ventricular flutter were statistically significantly decreased by 27.4% and 15.6%, respectively. BM 13.177 (30 mg/kg), a thromboxane receptor antagonizing substance, and esculetin (1.2 mg/kg), a lipoxygenase inhibitor, abolished this arrhythmogenic effect of PAF. Acetylsalicylic acid (10 mg/kg) showed only a tendency to inhibit the PAF effect. These results suggest that PAF could play a role in cardiac arrhythmias under special conditions and it supports the hypothesis that PAF action is mediated by the release of leukotrienes and thromboxane.
D000818:Animals; D001095:Arachidonic Acids / Q000502:physiology*; D001145:Arrhythmias, Cardiac / Q000139:chemically induced / Q000503:physiopathology*; D001241:Aspirin / Q000494:pharmacology; D005343:Fibrinolytic Agents / Q000494:pharmacology; D006168:Guinea Pigs; D016859:Lipoxygenase Inhibitors; D010042:Ouabain; D010972:Platelet Activating Factor / Q000037:antagonists & inhibitors / Q000502:physiology*; D013449:Sulfonamides / Q000494:pharmacology; D014468:Umbelliferones / Q000494:pharmacology
D001095:Arachidonic Acids; D005343:Fibrinolytic Agents; D016859:Lipoxygenase Inhibitors; D010972:Platelet Activating Factor; D013449:Sulfonamides; D014468:Umbelliferones; D010042:Ouabain; C040624:sulotroban; D001241:Aspirin; C007628:esculetin