Book of Abstracts - New Frontiers 2022

Abstracts of poster presentations

NITRIC OXIDE AS ONE OF THE TRIGGERING FACTORS OF CARDIOPROTECTION INDUCED BY REMOTE PRECONDITIONING

V. Farkasova, L. Kindernay, L. Lonek, T. Ravingerova

Centre of Experimental Medicine, Institute for Heart Research Slovak Academy of Sciences, Bratislava, Slovakia

Mechanisms of protection induced by remote preconditioning (RPC) represent a complex cascade of initial triggering in the remote tissue, communicationbetween the distant and the target organ, and end-effects responsible for the induction of the protective phenotype. The potential candidates for RPC triggering molecules includes, but is not limited to, nitric oxide (NO). The aim of the study was to investigate the roleof NO as a triggering molecule in the cardioprotective effect of RPC in male Wistar rats aged 3-4 months. The NOS inhibitor L-NAME (60 mg/kg i.p.) was applied to the rats 20 minutes before the anesthesia with/without RPC induction (RPC+L-NAME/C+L-NAME). The RPC protocol consisted of three cycles of 5 minute occlusion (ischemia) and 5 minute reperfusion of hind limb. Subsequently, the rat hearts were isolated for Langendorff perfusion and subjected to 20min stabilization, 30min global ischemia and 120min of reperfusion for the evaluation of post-ischemic contractile dysfunction, reperfusion arrhythmias and size of myocardial infarction. The recovery of LVDP (% of preischemic values) was significantely increased in RPC animals compare to Controls (58.5%±5.8 vs. 38.1%±4.7; p<0.05). Application of L -NAME suppressed this cardioprotective effect of RPC and LVDP recovery decreased in RPC+L-NAME group (RPC+L-NA ME 37.3%±6.8 vs. RPC 58.5%±5.8; p<0.05) to the level observed in Controls. Similarly L -NAME inhibited the anti-infarct effect of RPC. According to our observation we can conclude that NO molecules play rolein triggering cardioprotective effect of RPC in Wistar rats. Inhibition of NO triggering action led to an inability to further transmit the signal from the distant organ to the target tissue/organ and thus suppressed potential RPC induced protection.

Keywords: remote preconditioning, cardioprotection, nitric oxide, L-NAME

Funding: APVV-19-0540, VEGA 2/0141/18, VEGA 2/0104/22

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