Orthogonal analysis of aggravating effects of alpha-, beta-agonists and leukocytes on reperfusion-induced arrhythmias and ventricular fibrillation in Langendorff's rat heart.
OBJECTIVE
To study the effect 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 important one in exacerbating arrhythmias.


METHODS
Arrhythmias were induced by the reduction and subsequent resumption of perfused flow in Langendorff's perfused rat hearts. Ventricular tachycardia (VT) and ventricular fibrillation (VF) were recorded on ECG, and the results were orthogonally 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%, respectively. The results by orthogonal analysis demonstrated Leu or alpha-Ago+ beta-Ago increased VF incidence. With regard to arrhythmias, arrhythmia score was remarkedly increased by all of 3 factors and various combinations except beta-Ago + Leu.


CONCLUSIONS
Among these 3 factors, Leu was the most important one in facilitating reperfusion-induced arrhythmias.
Dai
D Z
DZ
Research Division of Pharmacology, China Pharmaceutical University, Nanjing, China.
An
L F
LF
Huang
D Y
DY
Sun
R Y
RY
D000316:Adrenergic alpha-Agonists / Q000009:adverse effects*; D000318:Adrenergic beta-Agonists / Q000009:adverse effects*; D000818:Animals; D001145:Arrhythmias, Cardiac / Q000201:enzymology / Q000209:etiology*; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000009:adverse effects*; D007962:Leukocytes / Q000502:physiology*; D015428:Myocardial Reperfusion Injury / Q000150:complications; D009206:Myocardium / Q000201:enzymology; D010656:Phenylephrine / Q000009:adverse effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013482:Superoxide Dismutase / Q000378:metabolism; D014693:Ventricular Fibrillation / Q000201:enzymology / Q000209:etiology*
D000316:Adrenergic alpha-Agonists; D000318:Adrenergic beta-Agonists; D010656:Phenylephrine; D013482:Superoxide Dismutase; D007545:Isoproterenol