Publications by authors named "N A Undrovinas"

Severe hypoxia leads to decline in cardiac contractility and induces arrhythmic events in part due to oxidative damage to cardiomyocyte proteins including ion transporters. This results in compromised handling of Ca ions that trigger heart contractile machinery. Here, we demonstrate that thiol-containing compounds such as N-acetylcysteine (NAC), glutathione ethyl ester (et-GSH), oxidized tetraethylglutathione (tet-GSSG), oxidized glutathione (GSSG) and S-nitrosoglutathione (GSNO) are capable of reducing negative effects of hypoxia on isolated rat cardiomyocytes.

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. Nitric oxide can successfully compete with oxygen for sites of electron-transport chain in conditions of myocardial hypoxia. These features may prevent excessive oxidative stress occurring in cardiomyocytes during sudden hypoxia-reoxygenation.

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We have demonstrated the phenomenon of Са(2+)-induced hyperpolarization in the myocardium of pulmonary veins (PVs) in rats. An increase in cytoplasmic calcium [Са(2+)] i was shown to shift the resting potential (RP) in the PVs towards more negative values. The compounds inducing an increase in [Са(2+)] i , such as isoproterenol (10 μM), caffeine (5 mM), and ryanodine (0.

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Introduction of isoproterenol (beta-adrenoreceptor agonist) into rats is one of the widespread experimental models of heart failure. It is caused by diffuse ischemic damage of cardiomyocytes, followed by development of substitutive fibrosis. Apelin is a natural regulator of the myocardial contractility.

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Key Points: Late Na(+) current (INaL) contributes to action potential remodelling and Ca(2+)/Na(+) changes in heart failure. The molecular identity of INaL remains unclear. The contributions of different Na(+) channel isoforms, apart from the cardiac isoform, remain unknown.

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