Cardiotoxic effects of enrofloxacin on electrophysiological activity, cardiac markers, oxidative stress, and haematological findings in rabbits

Abstract

IntroductionProlongation of the QT interval is commonly used as a surrogate marker of torsades de pointes (TdP), which is a known clinical risk factor for the development of severe, life-threatening, ventricular arrhythmias (Abi-Gerges et al., 2004). Noncardiovascular drug-induced prolongation of the QT interval is often associated with the onset of TdP (Haverkamp et al., 2000;De Ponti et al., 2001). Fluoroquinolones are among the drugs of choice for the treatment of common bacterial infections due to their wide spectrum against respiratory, gastrointestinal, and genitourinary pathogens (Elmas et al., 2006). QT interval prolongation is also a class effect of fluoroquinolones but there are great differences between the various members of this group (Camm, 2005). Thus, there are significant differences in the potency to prolong QT interval among the fluoroquinolones and the risk of arrhythmia varies between drugs and with co-risk factors (Frothingham, 2001;Owens and Ambrose, 2002). Because a QT prolongation and potentially fatal ventricular arrhythmias associated with quinolones such as grepafloxacin due to several cases of sudden death and TdP have been encountered retrospectively, enrofloxacin needs to be further investigated in detail. Therefore, the purpose of this study was to investigate the effect of normal and high doses of enrofloxacin on basal electrocardiographic parameters including heart rate (HR), P, QRS, QT, and RR intervals and corrected QT (QTc) values as well as biochemical and haematological findings in healthy conscious rabbits. Materials and methods ApprovalsThis study was approved by the Institutional Laboratory Animal Care and Use Committee of Mustafa Kemal University (2011 -01 -09). ChemicalsAll chemicals were obtained from Sigma Chemical Co, and solutions were prepared fresh daily from concentrated stock solutions. Animal preparationAfter 1 week of quarantine and acclimatisation, a total of 21 healthy New Zealand rabbits of both sexes, 12-18 months old, and of 2-4 kg body weight were used. The rabbits were housed individually in stainless-steel wire mesh cages and provided with food and water ad libitum. All rabbits were