Peroxynitrite in reperfusion arrhythmias and its whole blood chemiluminescence results

Abstract

The aims of the present study were to investigate the effects of exogenous peroxynitrite (ONOO −) on reperfusion arrhythmias in anaesthetized rats, and to detect endogenous and exogenous ONOO −-induced chemiluminescence (CL) signals in rat whole blood, which was collected during baseline and in the first minute of reperfusion. ONOO − infusion in ischemia/reperfusion (I/R) applied groups caused significant decreases in mean arterial pressure (MAP) and heart rate (HR). Ventricular fibrillation (VF) incidences in the vehicle, ONOO −, and dec-ONOO − infused groups were 63, 100, and 20%, respectively. In control group CL signal was 136±34 mV during the resting period and was increased to 336±57 mV with reperfusion. Also, the effects of SOD+CAT, l-NAME and urate were investigated. Ventricular tachycardia (VT) incidence was decreased significantly in SOD+CAT and urate; VF incidence was decreased significantly in SOD+CAT applied groups. CL signals were inhibited with SOD+CAT, l-NAME, and urate. Exogenous ONOO − infusion during I/R was also investigated. CL signal in exogenously ONOO − infused group is increased 423% during reperfusion. Only urate infused group VF incidence was decreased significantly. CL signals of ONOO − infused groups were inhibited by SOD+CAT, l-NAME, and urate. Based on the results of the current study, ONOO − seems to be one of the key mediators of reperfusion arrhythmias in anaesthetized rats.