Dissection of the Effects of Quercetin on Mouse Myocardium.

Autor: Santos MS; Laboratory of Heart Biophysics, Department of Physiology, Federal University of Sergipe, São Cristóvão, SE, Brazil., Oliveira ED; Laboratory of Heart Biophysics, Department of Physiology, Federal University of Sergipe, São Cristóvão, SE, Brazil.; Department of Physiotherapy, Federal University of Sergipe, São Cristóvão, SE, Brazil., Santos-Miranda A; Excitable Membranes Laboratory, Department of Biochemistry and Immunology, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil., Cruz JS; Excitable Membranes Laboratory, Department of Biochemistry and Immunology, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil., Gondim ANS; Laboratory of Biophysics and Pharmacology of the Heart, Department of Education, Campus XII, University of the State of Bahia, Guanambi, BA, Brazil., Menezes-Filho JER; Laboratory of Heart Biophysics, Department of Physiology, Federal University of Sergipe, São Cristóvão, SE, Brazil., Souza DS; Laboratory of Heart Biophysics, Department of Physiology, Federal University of Sergipe, São Cristóvão, SE, Brazil., Pinho-da-Silva L; Excitable Membranes Laboratory, Department of Biochemistry and Immunology, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil., Jesus ICG; Cardiomyocyte Intracellular Signaling Laboratory, Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil., Roman-Campos D; Department of Biophysics, Federal University of São Paulo, São Paulo, Brazil., Guatimosim S; Cardiomyocyte Intracellular Signaling Laboratory, Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil., Lara A; Cardiomyocyte Intracellular Signaling Laboratory, Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil., Conde-Garcia EA; Laboratory of Heart Biophysics, Department of Physiology, Federal University of Sergipe, São Cristóvão, SE, Brazil., Vasconcelos CML; Laboratory of Heart Biophysics, Department of Physiology, Federal University of Sergipe, São Cristóvão, SE, Brazil.
Jazyk: angličtina
Zdroj: Basic & clinical pharmacology & toxicology [Basic Clin Pharmacol Toxicol] 2017 Jun; Vol. 120 (6), pp. 550-559. Date of Electronic Publication: 2017 Mar 14.
DOI: 10.1111/bcpt.12743
Abstrakt: Quercetin is a plant flavonoid with several biological activities. This study aimed to describe quercetin effects on contractile and electrophysiological properties of the cardiac muscle as well as on calcium handling. Quercetin elicited positive inotropism that was significantly reduced by propranolol indicating an involvement of the sympathetic nervous system. In cardiomyocytes, 30 μM quercetin increased I Ca,L at 0 mV from -0.95 ± 0.01 A/F to -1.21 ± 0.08 A/F. The membrane potential at which 50% of the channels are activated (V 0.5 ) shifted towards more negative potentials from -13.06 ± 1.52 mV to -19.26 ± 1.72 mV and did not alter the slope factor. Furthermore, quercetin increased [Ca 2+ ] i transient by 28% when compared to control. Quercetin accelerated [Ca 2+ ] i transient decay time, which could be attributed to SERCA activation. In resting cardiomyocytes, quercetin did not change amplitude or frequency of Ca 2+ sparks. In isolated heart, quercetin increased heart rate and decreased PRi, QTc and duration of the QRS complex. Thus, we showed that quercetin activates β-adrenoceptors, leading to increased L-type Ca 2+ current and cell-wide intracellular Ca 2+ transient without visible changes in Ca 2+ sparks.
(© 2016 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).)
Databáze: MEDLINE
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