ORTHOGONAL ANALYSIS OF AGGRAVATING EFFECTS OF ALPHA-AGONIST, BETA-AGONIST AND LEUKOCYTES ON REPERFUSION-INDUCED ARRHYTHMIAS AND VENTRICULAR-FIBRILLATION IN LANGENDORFFS RAT-HEART

AIM: To study the effects of leukocyte (Leu), alpha-agonist (alpha-Ago ), and beta-agonist (beta-Ago) on the arrhythmias induced by ischemia and reperfusion to determine which of the 3 factors was the most impor tant one in exacerbating arrhythmias. METHODS: Arrhythmias were induce d by the reduction and subsequent resumption of perfused flow in Lange ndorff's perfused rat hearts. Ventricular tachycardia (VT) and ventric ular fibrillation (VF) were recorded on EGG, and the results were orth ogonally analyzed. RESULTS: When Leu was present, the incidence of VF induced by ischemia-reperfusion was 80%. The incidence in Leu-depleted hearts was 20%, alpha-Ago and beta-Ago elevated it to 60% and 100%, r espectively. The results by orthogonal analysis demonstrated Leu or al pha-Ago(+)beta-Ago increased VF incidence. With regard to arrhythmias, arrhythmia score was remarkedly increased by all of 3 factors and var ious combinations except beta-Ago + Leu. CONCLUSION: Among these 3 fac tors, Leu was the most important one in facilitating reperfusion-induc ed arrhythmias.