Does prevention of free radical reactions influence digoxin-arrhythmias?
In the present study, the possible role of oxygen-derived free radicals (OFR) on digoxin- (0.6 mg/kg(-1) IV bolus) induced arrhythmias of anesthetized guinea-pigs has been investigated. Guinea-pigs (300400 g) of either sex were anesthetized with urethane (1.5 g/kg(-1),IP), and their trachea for respiration, left common carotid artery for blood pressure monitoring, and right jugular vein for drug administration were cannulated. ECG and haemodynamics were recorded throughout the experiments. None of the agents used [N-acetyl-L-cysteine (20 mg/kg(-1)IV bolus), or SOD (30,000 IU/kg(-1) IV bolus) + catalase (15,000 IU/kg(-1) IV bolus)] significantly inhibited the arrhythmias except desferrioxamine which reduced the incidence of ventricular fibrillation and arrhythmia score. Desferrioxamine, by acting intracellularly unlike other agents used, might prevent the reduction of Fe(+3) by ascorbate and superoxide anion thus inhibiting the formation of cytotoxic hydroxyl radical in this experimental setting.
Ark
M
M
Department of Pharmacology, Faculty of Pharmacy, Gazi University, Ankara, Turkey.
Cakici
I
I
Sariahmetoğlu
M
M
Kanzik
I
I
D000818:Animals; D000975:Antioxidants / Q000627:therapeutic use*; D001145:Arrhythmias, Cardiac / Q000139:chemically induced / Q000503:physiopathology / Q000517:prevention & control*; D004077:Digoxin / Q000633:toxicity*; D004562:Electrocardiography / Q000187:drug effects; D005260:Female; D016166:Free Radical Scavengers / Q000627:therapeutic use*; D005609:Free Radicals / Q000378:metabolism; D006168:Guinea Pigs; D008297:Male; D017382:Reactive Oxygen Species / Q000378:metabolism / Q000502:physiology; D017180:Tachycardia, Ventricular / Q000139:chemically induced; D014693:Ventricular Fibrillation / Q000139:chemically induced
D000975:Antioxidants; D016166:Free Radical Scavengers; D005609:Free Radicals; D017382:Reactive Oxygen Species; D004077:Digoxin