It was found that pretreatment of rats with selective agonist of kappa1-opioid receptors (OR) (-)--U--50.488 decreased the incidence of ischemic (10 min) and reperfusion (10 min) ventricular arrhythmias. The selective kappa2-OR agonist GR-89696 had no effect on the incidence of ventricular arrhythmias during a 10-min coronary artery occlusion and following reperfusion in anesthetized rats. The effect of (-)--U-50.488 was abolished by the selective kappa1-OR antagonist of non-binaltorphimine and the non-selective peripheral OR antagonist naloxone methiodide. Perfusion of isolated rat heart with (-)--U-50.488 did not affect arrhythmias during ischemia and reperfusion. The authors suggest that stimulation of kappa1-opioid receptors located outside the central nervous system increases heart resistance against arrhythmogenic action of ischemia/reperfusion, antiarrhythmic action of (-)--U-50.488 being mediated through extracardiac opioid receptors.
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Int J Mol Sci
December 2024
Institute of Molecular Physiology and Genetics, Centre of Biosciences, Slovak Academy of Sciences, Dubravska cesta 9, 840 05 Bratislava, Slovakia.
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December 2024
Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21205, United States; Department of Medicine, Johns Hopkins University, Baltimore, MD, 21205, United States; Institute for NanoBio Technology, Johns Hopkins University, Baltimore, MD, 21218, United States; Center for Microphysiological Systems, Johns Hopkins University, Baltimore, MD, 21205, United States. Electronic address:
Cardiotoxicity remains a major challenge in drug development, accounting for 45% of medication withdrawals due to cardiac ischemia and arrhythmogenicity. To overcome the limitations of traditional multielectrode array (MEA)-based cardiotoxicity assays, we developed a Nafion-coated NanoMEA platform with decoupled reference electrodes, offering enhanced sensitivity for electrophysiological measurements. The 'Decoupled' configuration significantly reduced polarization resistance (Rp) from 12.
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Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Splaiul Independentei 91-95, 050095 Bucharest, Romania.
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View Article and Find Full Text PDFStem Cell Rev Rep
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Laboratory of Physiology and Cardiac Pathophysiology, Department of Medicine, Federal University of São Paulo, São Paulo, SP, Brazil.
This study evaluated the role of the mesenchymal stem cells derived from adipose tissue (MSCs) in provoked ventricular arrhythmias (VAs) in animals with myocardial infarction (MI). The experimental groups were: sham, subjected to sham surgery and intramyocardial saline injection; MIV, infarcted rats subjected to intramyocardial saline injection; MI + MSCs, infarcted rats subjected to intramyocardial MSCs injection. Injections were performed two days after infarction and the arrhythmogenic inducibility experiment was performed the next day.
View Article and Find Full Text PDFFront Cardiovasc Med
July 2024
Department of Internal Medicine II/Cardiology, University Medical Center Regensburg, Regensburg, Germany.
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