0309 : Cardioprotective effect of a novel snake venom derived natriuretic peptide during myocardial ischemia reperfusion injury

IntroductionIn this study, we aimed at testing the therapeutic potential of a novel Natriuretic Peptide (NPs), identified from Tunisian snake venom, when administered during reperfusion.Materials and MethodsLangendorff perfused male Wistar rat hearts were subjected to 30min regional coronary artery occlusion followed by 90min reperfusion. Hearts were treated either with brain natriuretic peptide BNP (10nM) or NPs (200nM). In another set of experiments, hearts were pretreated with either isatin (100μM), a natriuretic peptide receptors blocker or 5HD (10μM), a mitochondrial KATP channels blocker. Post ischemic cardiac haemodynamic parameters, using Labt Chart (ADInstruments) and infarct size (IS), using planimetry, were evaluated. Western blotting experiments for studying cGMP and Reperfusion Injury Salvage Kinases pathways were performed. Calcium Retention Capacity (CRC) to evaluate the mitochondrial function was also assessed by oxygraphy.ResultsBNP and NPs significantly decreased the IS by 60% and 62% respectively compared to control non treated hearts (p<0.001). Regarding hemodynamic parameters, both BNP and NPs improved the developed pressure (DP) by 135% and 152% respectively (p