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Ritzer A, Roeschl T, Nay S, Rudakova E, Volk T. Rapid Pacing Decreases L-type Ca 2+ Current and Alters Cacna1c Isogene Expression in Primary Cultured Rat Left Ventricular Myocytes. J Membr Biol 2023; 256:257-269. [PMID: 36995425 DOI: 10.1007/s00232-023-00284-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 03/14/2023] [Indexed: 03/31/2023]
Abstract
The L-type calcium current (ICaL) is the first step in cardiac excitation-contraction-coupling and plays an important role in regulating contractility, but also in electrical and mechanical remodeling. Primary culture of cardiomyocytes, a widely used tool in cardiac ion channel research, is associated with substantial morphological, functional and electrical changes some of which may be prevented by electrical pacing. We therefore investigated ICaL directly after cell isolation and after 24 h of primary culture with and without regular pacing at 1 and 3 Hz in rat left ventricular myocytes. Moreover, we analyzed total mRNA expression of the pore forming subunit of the L-type Ca2+ channel (cacna1c) as well as the expression of splice variants of its exon 1 that contribute to specificity of ICaL in different tissue such as cardiac myocytes or smooth muscle. 24 h incubation without pacing decreased ICaL density by ~ 10% only. Consistent with this decrease we observed a decrease in the expression of total cacna1c and of exon 1a, the dominant variant of cardiomyocytes, while expression of exon 1b and 1c increased. Pacing for 24 h at 1 and 3 Hz led to a substantial decrease in ICaL density by 30%, mildly slowed ICaL inactivation and shifted steady-state inactivation to more negative potentials. Total cacna1c mRNA expression was substantially decreased by pacing, as was the expression of exon 1b and 1c. Taken together, electrical silence introduces fewer alterations in ICaL density and cacna1c mRNA expression than pacing for 24 h and should therefore be the preferred approach for primary culture of cardiomyocytes.
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Affiliation(s)
- Anne Ritzer
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Waldstraße 6, 91054, Erlangen, Germany
| | - Tobias Roeschl
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Waldstraße 6, 91054, Erlangen, Germany
| | - Sandra Nay
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Waldstraße 6, 91054, Erlangen, Germany
| | - Elena Rudakova
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Waldstraße 6, 91054, Erlangen, Germany
| | - Tilmann Volk
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Waldstraße 6, 91054, Erlangen, Germany.
- Muscle Research Center Erlangen (MURCE), Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054, Erlangen, Germany.
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de las Heras N, Galiana A, Ballesteros S, Olivares-Álvaro E, Fuller PJ, Lahera V, Martín-Fernández B. Proanthocyanidins Maintain Cardiac Ionic Homeostasis in Aldosterone-Induced Hypertension and Heart Failure. Int J Mol Sci 2021; 22:ijms22179602. [PMID: 34502509 PMCID: PMC8431754 DOI: 10.3390/ijms22179602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 08/31/2021] [Accepted: 08/31/2021] [Indexed: 11/16/2022] Open
Abstract
Excess aldosterone promotes pathological remodeling of the heart and imbalance in cardiac ion homeostasis of sodium, potassium and calcium. Novel treatment with proanthocyanidins in aldosterone-treated rats has resulted in downregulation of cardiac SGK1, the main genomic aldosterone-induced intracellular mediator of ion handling. It therefore follows that proanthocyanidins could be modulating cardiac ion homeostasis in aldosterone-treated rats. Male Wistar rats received aldosterone (1 mg kg−1 day−1) +1% NaCl for three weeks. Half of the animals in each group were simultaneously treated with the proanthocyanidins-rich extract (80% w/w) (PRO80, 5 mg kg−1 day−1). PRO80 prevented cardiac hypertrophy and decreased calcium content. Expression of ion channels (ROMK, NHE1, NKA and NCX1) and calcium transient mediators (CAV1.2, pCaMKII and oxCaMKII) were reduced by PRO80 treatment in aldosterone-treated rats. To conclude, our data indicate that PRO80 may offer an alternative treatment to conventional MR-blockade in the prevention of aldosterone-induced cardiac pathology.
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Affiliation(s)
- Natalia de las Heras
- Department of Physiology, Faculty of Medicine, Plaza Ramón y Cajal, s/n. Universidad Complutense, 28040 Madrid, Spain; (N.d.l.H.); (A.G.); (S.B.); (E.O.-Á.); (V.L.)
| | - Adrián Galiana
- Department of Physiology, Faculty of Medicine, Plaza Ramón y Cajal, s/n. Universidad Complutense, 28040 Madrid, Spain; (N.d.l.H.); (A.G.); (S.B.); (E.O.-Á.); (V.L.)
| | - Sandra Ballesteros
- Department of Physiology, Faculty of Medicine, Plaza Ramón y Cajal, s/n. Universidad Complutense, 28040 Madrid, Spain; (N.d.l.H.); (A.G.); (S.B.); (E.O.-Á.); (V.L.)
| | - Elena Olivares-Álvaro
- Department of Physiology, Faculty of Medicine, Plaza Ramón y Cajal, s/n. Universidad Complutense, 28040 Madrid, Spain; (N.d.l.H.); (A.G.); (S.B.); (E.O.-Á.); (V.L.)
| | - Peter J. Fuller
- Centre for Endocrinology and Metabolism, Hudson Institute of Medical Research, Clayton, VIC 3168, Australia;
| | - Vicente Lahera
- Department of Physiology, Faculty of Medicine, Plaza Ramón y Cajal, s/n. Universidad Complutense, 28040 Madrid, Spain; (N.d.l.H.); (A.G.); (S.B.); (E.O.-Á.); (V.L.)
| | - Beatriz Martín-Fernández
- Department of Physiology, Faculty of Medicine, Plaza Ramón y Cajal, s/n. Universidad Complutense, 28040 Madrid, Spain; (N.d.l.H.); (A.G.); (S.B.); (E.O.-Á.); (V.L.)
- Department of Molecular Biology, Faculty of Biology, Universidad de León, Campus de Vegazana s/n, 24071 León, Spain
- Correspondence: ; Tel.: +34-987-291-000 (ext. 3650)
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Wacker C, Dams N, Schauer A, Ritzer A, Volk T, Wagner M. Region-specific mechanisms of corticosteroid-mediated inotropy in rat cardiomyocytes. Sci Rep 2020; 10:11604. [PMID: 32665640 PMCID: PMC7360564 DOI: 10.1038/s41598-020-68308-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 06/23/2020] [Indexed: 11/09/2022] Open
Abstract
Regional differences in ion channel activity in the heart control the sequence of repolarization and may contribute to differences in contraction. Corticosteroids such as aldosterone or corticosterone increase the L-type Ca2+ current (ICaL) in the heart via the mineralocorticoid receptor (MR). Here, we investigate the differential impact of corticosteroid-mediated increase in ICaL on action potentials (AP), ion currents, intracellular Ca2+ handling and contractility in endo- and epicardial myocytes of the rat left ventricle. Dexamethasone led to a similar increase in ICaL in endocardial and epicardial myocytes, while the K+ currents Ito and IK were unaffected. However, AP duration (APD) and AP-induced Ca2+ influx (QCa) significantly increased exclusively in epicardial myocytes, thus abrogating the normal differences between the groups. Dexamethasone increased Ca2+ transients, contractility and SERCA activity in both regions, the latter possibly due to a decrease in total phospholamban (PLB) and an increase PLBpThr17. These results suggest that corticosteroids are powerful modulators of ICaL, Ca2+ transients and contractility in both endo- and epicardial myocytes, while APD and QCa are increased in epicardial myocytes only. This indicates that increased ICaL and SERCA activity rather than QCa are the primary drivers of contractility by adrenocorticoids.
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Affiliation(s)
- Caroline Wacker
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Waldstraße 6, 91054, Erlangen, Germany
| | - Niklas Dams
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Waldstraße 6, 91054, Erlangen, Germany
| | - Alexander Schauer
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Waldstraße 6, 91054, Erlangen, Germany
| | - Anne Ritzer
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Waldstraße 6, 91054, Erlangen, Germany
| | - Tilmann Volk
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Waldstraße 6, 91054, Erlangen, Germany. .,Muscle Research Center Erlangen (MURCE), Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
| | - Michael Wagner
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Waldstraße 6, 91054, Erlangen, Germany. .,Abteilung für Rhythmologie, Herzzentrum Dresden, Fetscherstraße 76, 01307, Dresden, Germany.
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Ito J. [Steroid hormones' genomic and non-genomic actions on cardiac voltage-gated calcium channels]. Nihon Yakurigaku Zasshi 2014; 144:206-210. [PMID: 25381888 DOI: 10.1254/fpj.144.206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
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Mineralocorticoid receptors and the heart, multiple cell types and multiple mechanisms: a focus on the cardiomyocyte. Clin Sci (Lond) 2013; 125:409-21. [PMID: 23829554 DOI: 10.1042/cs20130050] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
MR (mineralocorticoid receptor) activation in the heart plays a central role in the development of cardiovascular disease, including heart failure. The MR is present in many cell types within the myocardium, including cardiomyocytes, macrophages and the coronary vasculature. The specific role of the MR in each of these cell types in the initiation and progression of cardiac pathophysiology is not fully understood. Cardiomyocyte MRs are increasingly recognized to play a role in regulating cardiac function, electrical conduction and fibrosis, through direct signal mediation and through paracrine MR-dependent activity. Although MR blockade in the heart is an attractive therapeutic option for the treatment of heart failure and other forms of heart disease, current antagonists are limited by side effects owing to MR inactivation in other tissues (including renal targets). This has led to increased efforts to develop therapeutics that are more selective for cardiac MRs and which may have reduced the occurrence of side effects in non-cardiac tissues. A major clinical consideration in the treatment of cardiovascular disease is of the differences between males and females in the incidence and outcomes of cardiac events. There is clinical evidence that female sensitivity to endogenous MRs is more pronounced, and experimentally that MR-targeted interventions may be more efficacious in females. Given that sex differences have been described in MR signalling in a range of experimental settings and that the MR and oestrogen receptor pathways share some common signalling intermediates, it is becoming increasingly apparent that the mechanisms of MRs need to be evaluated in a sex-selective manner. Further research targeted to identify sex differences in cardiomyocyte MR activation and signalling processes has the potential to provide the basis for the development of cardiac-specific MR therapies that may also be sex-specific.
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Song YH. A Memory Molecule, Ca(2+)/Calmodulin-Dependent Protein Kinase II and Redox Stress; Key Factors for Arrhythmias in a Diseased Heart. Korean Circ J 2013; 43:145-51. [PMID: 23613689 PMCID: PMC3629238 DOI: 10.4070/kcj.2013.43.3.145] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Arrhythmias can develop in various cardiac diseases, such as ischemic heart disease, cardiomyopathy and congenital heart disease. It can also contribute to the aggravation of heart failure and sudden cardiac death. Redox stress and Ca2+ overload are thought to be the important triggering factors in the generation of arrhythmias in failing myocardium. From recent studies, it appears evident that Ca2+/calmodulin-dependent protein kinase II (CaMKII) plays a central role in the arrhythmogenic processes in heart failure by sensing intracellular Ca2+ and redox stress, affecting individual ion channels and thereby leading to electrical instability in the heart. CaMKII, a multifunctional serine/threonine kinase, is an abundant molecule in the neuron and the heart. It has a specific property as "a memory molecule" such that the binding of calcified calmodulin (Ca2+/CaM) to the regulatory domain on CaMKII initially activates this enzyme. Further, it allows autophosphorylation of T287 or oxidation of M281/282 in the regulatory domain, resulting in sustained activation of CaMKII even after the dissociation of Ca2+/CaM. This review provides the understanding of both the structural and functional properties of CaMKII, the experimental findings of the interactions between CaMKII, redox stress and individual ion channels, and the evidences proving the potential participation of CaMKII and oxidative stress in the diverse arrhythmogenic processes in a diseased heart.
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Affiliation(s)
- Young-Hwan Song
- Department of Pediatrics, Sanggye Paik Hospital, College of Medicine, Inje University, Seoul, Korea
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Fairhall EA, Wallace K, White SA, Huang GC, Shaw JA, Wright SC, Charlton KA, Burt AD, Wright MC. Adult human exocrine pancreas differentiation to hepatocytes – potential source of a human hepatocyte progenitor for use in toxicology research. Toxicol Res (Camb) 2013. [DOI: 10.1039/c2tx20061a] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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Erickson JR, He BJ, Grumbach IM, Anderson ME. CaMKII in the cardiovascular system: sensing redox states. Physiol Rev 2011; 91:889-915. [PMID: 21742790 DOI: 10.1152/physrev.00018.2010] [Citation(s) in RCA: 176] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The multifunctional Ca(2+)- and calmodulin-dependent protein kinase II (CaMKII) is now recognized to play a central role in pathological events in the cardiovascular system. CaMKII has diverse downstream targets that promote vascular disease, heart failure, and arrhythmias, so improved understanding of CaMKII signaling has the potential to lead to new therapies for cardiovascular disease. CaMKII is a multimeric serine-threonine kinase that is initially activated by binding calcified calmodulin (Ca(2+)/CaM). Under conditions of sustained exposure to elevated Ca(2+)/CaM, CaMKII transitions into a Ca(2+)/CaM-autonomous enzyme by two distinct but parallel processes. Autophosphorylation of threonine-287 in the CaMKII regulatory domain "traps" CaMKII into an open configuration even after Ca(2+)/CaM unbinding. More recently, our group identified a pair of methionines (281/282) in the CaMKII regulatory domain that undergo a partially reversible oxidation which, like autophosphorylation, prevents CaMKII from inactivating after Ca(2+)/CaM unbinding. Here we review roles of CaMKII in cardiovascular disease with an eye to understanding how CaMKII may act as a transduction signal to connect pro-oxidant conditions into specific downstream pathological effects that are relevant to rare and common forms of cardiovascular disease.
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Affiliation(s)
- Jeffrey R Erickson
- Department of Pharmacology, University of California at Davis, Davis, California 95616, USA.
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Wagner M, Moritz A, Volk T. Interaction of gonadal steroids and the glucocorticoid corticosterone in the regulation of the L-type Ca(2+) current in rat left ventricular cardiomyocytes. Acta Physiol (Oxf) 2011; 202:629-40. [PMID: 21477069 DOI: 10.1111/j.1748-1716.2011.02303.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
AIM Gonadal steroids as well as glucocorticoids have been shown to regulate the cardiac L-type Ca(2+) current (I(CaL) ). Herein, we compare the effects of the gonadal steroids testosterone and 17β-estradiol with the glucocorticoid corticosterone on I(CaL) , and investigate the interaction between the gonadal steroids and corticosterone. METHODS Myocytes were isolated from the left ventricular free wall of female and male Wistar rats and investigated using the ruptured-patch whole-cell patch-clamp technique. RESULTS In myocytes isolated from female rats, 24 h incubation with 100 nm testosterone led to a 33% increase in I(CaL) compared with control (-8.8 ± 0.5 pA pF(-1) , n = 25 vs. -6.6 ± 0.4 pA pF(-1) , n = 26, P < 0.01, V(Pip) = 0 mV). Incubation with 1 μm corticosterone resulted in a 79% increase in I(CaL) (-11.8 ± 0.7 pA pF(-1) , n = 29, P < 0.001). However, the combination of testosterone and corticosterone did not have any additional effect compared with corticosterone alone (-11.7 ± 0.6 pA pF(-1) , n = 25, ns). In cardiomyocytes from male rats, I(CaL) was not affected by testosterone, whereas the effect of corticosterone was preserved (P < 0.05). 24 h incubation with 17β-estradiol increased I(CaL) by 32% from -7.6 ± 0.5 pA pF(-1) (n = 15) to 10.0 ± 0.9 pA pF(-1) (n = 15, P < 0.05). 17β-estradiol did not exert an additional effect upon co-incubation with corticosterone and did not have an effect on I(CaL) in cardiomyocytes from female rats. Higher concentrations of the gonadal steroids did not result in increased effects. CONCLUSION When compared with corticosterone, the in vitro effects of the gonadal steroids are small. However, under conditions in which I(CaL) is not fully activated by glucocorticoids, gonadal steroids may significantly contribute to I(CaL) regulation.
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Affiliation(s)
- M Wagner
- Institut für Zelluläre und Molekulare Physiologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany.
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Dartsch T, Fischer R, Gapelyuk A, Weiergraeber M, Ladage D, Schneider T, Schirdewan A, Reuter H, Mueller-Ehmsen J, Zobel C. Aldosterone induces electrical remodeling independent of hypertension. Int J Cardiol 2011; 164:170-8. [PMID: 21764470 DOI: 10.1016/j.ijcard.2011.06.100] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2010] [Revised: 05/17/2011] [Accepted: 06/18/2011] [Indexed: 12/26/2022]
Abstract
BACKGROUND Treatment of heart failure patients with aldosterone antagonists has been shown to reduce the occurrence of sudden cardiac death. Therefore we aimed at determining the consequences of chronic exposure to aldosterone and the aldosterone antagonists eplerenone and spironolactone on the electrophysiological properties of the heart in a rat model. METHODS AND RESULTS Male Wistar rats were chronically treated (4weeks) with aldosterone (ALD) via an osmotic minipump. Spironolactone (SPI) or eplerenone (EPL) was administered with the rat chow. ALD treated animals developed left ventricular hypertrophy, prolonged QT-intervals, a higher rate of ventricular premature beats and non-sustained ventricular tachycardia despite normal blood pressure values. Spironolactone and eplerenone were both able to inhibit the alterations. Left-ventricular mRNA expressions of Kv4.2 and Kv4.3 (Ito), Kv1.5 (IKur), Kir2.1 and Kir2.3 (IK1) and of Cav1.2 (L-type Ca(2+) channel) were significantly down-regulated in ALD. Correspondingly, the protein expressions of subunits Kv1.5, Kir2.3 and Cav1.2 were significantly decreased. A diminished calcineurin activity and mRNA expression of the Aß subunit of calcineurin were found in ALD, which was insensitive to aldosterone antagonists. CONCLUSIONS Chronic aldosterone-overload induces blood pressure independent structural and electrical remodeling of the myocardium resulting in an increased risk for malignant ventricular arrhythmias.
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Affiliation(s)
- Theresa Dartsch
- Department of Internal Medicine III, University of Cologne, Cologne, Germany
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Maggio N, Segal M. Cellular basis of a rapid effect of mineralocorticosteroid receptors activation on LTP in ventral hippocampal slices. Hippocampus 2010; 22:267-75. [DOI: 10.1002/hipo.20893] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/25/2010] [Indexed: 12/22/2022]
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Open channel block of the fast transient outward K+ current by primaquine and chloroquine in rat left ventricular cardiomyocytes. Eur J Pharmacol 2010; 647:13-20. [PMID: 20807529 DOI: 10.1016/j.ejphar.2010.08.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Revised: 07/02/2010] [Accepted: 08/12/2010] [Indexed: 12/25/2022]
Abstract
Anti-malarial drugs may have severe adverse cardiac effects as a result of their ion channel blocking properties. Here we investigate the effect of the aminoquinolines primaquine and chloroquine on the fast transient outward K(+) current (I(to)) of single epicardial myocytes isolated from the left ventricular free wall of female Wistar rats. The ruptured-patch whole-cell configuration of the patch-clamp technique was used to investigate I(to). At +60 mV, primaquine blocked I(to) amplitude (defined as the current inactivating during a test pulse of 600 ms duration) with an IC(50) of 118±8 μM. I(to) charge was blocked with an IC(50) of 33±2 μM (n=42), indicating open channel block. Chloroquine blocked I(to) amplitude with an IC(50) of 4.6±0.9 mM, while the IC(50) for I(to) charge was 439±63 μM (n=23). The kinetic analysis of the onset of block revealed K(d) values of 52±8 μM (n=18) and 520±60μM (n=11) for primaquine and chloroquine, respectively. Both drugs significantly accelerated the apparent inactivation time constant of I(to). Steady-state inactivation of I(to) was not altered by 30 μM primaquine. In contrast, I(to) recovery from inactivation was prolonged with the appearance of an additional long time constant without a change of the short time constant. Exposure to 1mM chloroquine resulted in a right shift of steady-state inactivation, whereas recovery from inactivation was only mildly affected. Both substances exhibited considerable use dependence. In X. laevis oocytes heterologously expressing hKv4.2+hKChIP2b channels the block by the aminoquinolines was voltage dependent. We conclude that primaquine and chloroquine are open-channel blockers of I(to).
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Abstract
Alteration of neurohormonal homeostasis is a hallmark of the pathophysiology of chronic heart failure (CHF). In particular, overactivation of the renin-angiotensin-aldosterone system and the sympathetic catecholaminergic system is consistently observed. Chronic overactivation of these hormonal pathways leads to a detrimental arrhythmogenic remodeling of cardiac tissue due to dysregulation of cardiac ion channels. Sudden cardiac death resulting from ventricular arrhythmias is a major cause of mortality in patients with CHF. All the drug classes known to reduce mortality in patients with CHF are neurohormonal blockers. The aim of this review was to provide an overview of how cardiac ion channels are regulated by hormones known to play a central role in the pathogenesis of CHF.
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Actions of aldosterone in the cardiovascular system: the good, the bad, and the ugly? Pflugers Arch 2008; 458:231-46. [DOI: 10.1007/s00424-008-0616-0] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Accepted: 10/30/2008] [Indexed: 01/11/2023]
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