1
|
Mitrokhin V, Hadzi-Petrushev N, Kazanski V, Schileyko S, Kamkina O, Rodina A, Zolotareva A, Zolotarev V, Kamkin A, Mladenov M. The Role of K ACh Channels in Atrial Fibrillation. Cells 2024; 13:1014. [PMID: 38920645 PMCID: PMC11201540 DOI: 10.3390/cells13121014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 06/05/2024] [Accepted: 06/07/2024] [Indexed: 06/27/2024] Open
Abstract
This manuscript explores the intricate role of acetylcholine-activated inward rectifier potassium (KACh) channels in the pathogenesis of atrial fibrillation (AF), a common cardiac arrhythmia. It delves into the molecular and cellular mechanisms that underpin AF, emphasizing the vital function of KACh channels in modulating the atrial action potential and facilitating arrhythmogenic conditions. This study underscores the dual nature of KACh activation and its genetic regulation, revealing that specific variations in potassium channel genes, such as Kir3.4 and K2P3.1, significantly influence the electrophysiological remodeling associated with AF. Furthermore, this manuscript identifies the crucial role of the KACh-mediated current, IKACh, in sustaining arrhythmia through facilitating shorter re-entry circuits and stabilizing the re-entrant circuits, particularly in response to vagal nerve stimulation. Experimental findings from animal models, which could not induce AF in the absence of muscarinic activation, highlight the dependency of AF induction on KACh channel activity. This is complemented by discussions on therapeutic interventions, where KACh channel blockers have shown promise in AF management. Additionally, this study discusses the broader implications of KACh channel behavior, including its ubiquitous presence across different cardiac regions and species, contributing to a comprehensive understanding of AF dynamics. The implications of these findings are profound, suggesting that targeting KACh channels might offer new therapeutic avenues for AF treatment, particularly in cases resistant to conventional approaches. By integrating genetic, cellular, and pharmacological perspectives, this manuscript offers a holistic view of the potential mechanisms and therapeutic targets in AF, making a significant contribution to the field of cardiac arrhythmia research.
Collapse
Affiliation(s)
- Vadim Mitrokhin
- Institute of Physiology, Federal State Autonomous Educational Institution of Higher Education “N.I. Pirogov, Russian National Research Medical University” Ministry of Health, 117997 Moscow, Russia; (V.M.); (V.K.); (S.S.); (O.K.); (A.R.); (A.Z.); (V.Z.); (A.K.)
| | - Nikola Hadzi-Petrushev
- Institute of Biology, Faculty of Natural Sciences and Mathematics, Ss. Cyril and Methodius University, 1000 Skopje, North Macedonia;
| | - Viktor Kazanski
- Institute of Physiology, Federal State Autonomous Educational Institution of Higher Education “N.I. Pirogov, Russian National Research Medical University” Ministry of Health, 117997 Moscow, Russia; (V.M.); (V.K.); (S.S.); (O.K.); (A.R.); (A.Z.); (V.Z.); (A.K.)
| | - Stanislav Schileyko
- Institute of Physiology, Federal State Autonomous Educational Institution of Higher Education “N.I. Pirogov, Russian National Research Medical University” Ministry of Health, 117997 Moscow, Russia; (V.M.); (V.K.); (S.S.); (O.K.); (A.R.); (A.Z.); (V.Z.); (A.K.)
| | - Olga Kamkina
- Institute of Physiology, Federal State Autonomous Educational Institution of Higher Education “N.I. Pirogov, Russian National Research Medical University” Ministry of Health, 117997 Moscow, Russia; (V.M.); (V.K.); (S.S.); (O.K.); (A.R.); (A.Z.); (V.Z.); (A.K.)
| | - Anastasija Rodina
- Institute of Physiology, Federal State Autonomous Educational Institution of Higher Education “N.I. Pirogov, Russian National Research Medical University” Ministry of Health, 117997 Moscow, Russia; (V.M.); (V.K.); (S.S.); (O.K.); (A.R.); (A.Z.); (V.Z.); (A.K.)
| | - Alexandra Zolotareva
- Institute of Physiology, Federal State Autonomous Educational Institution of Higher Education “N.I. Pirogov, Russian National Research Medical University” Ministry of Health, 117997 Moscow, Russia; (V.M.); (V.K.); (S.S.); (O.K.); (A.R.); (A.Z.); (V.Z.); (A.K.)
| | - Valentin Zolotarev
- Institute of Physiology, Federal State Autonomous Educational Institution of Higher Education “N.I. Pirogov, Russian National Research Medical University” Ministry of Health, 117997 Moscow, Russia; (V.M.); (V.K.); (S.S.); (O.K.); (A.R.); (A.Z.); (V.Z.); (A.K.)
| | - Andre Kamkin
- Institute of Physiology, Federal State Autonomous Educational Institution of Higher Education “N.I. Pirogov, Russian National Research Medical University” Ministry of Health, 117997 Moscow, Russia; (V.M.); (V.K.); (S.S.); (O.K.); (A.R.); (A.Z.); (V.Z.); (A.K.)
| | - Mitko Mladenov
- Institute of Physiology, Federal State Autonomous Educational Institution of Higher Education “N.I. Pirogov, Russian National Research Medical University” Ministry of Health, 117997 Moscow, Russia; (V.M.); (V.K.); (S.S.); (O.K.); (A.R.); (A.Z.); (V.Z.); (A.K.)
- Institute of Biology, Faculty of Natural Sciences and Mathematics, Ss. Cyril and Methodius University, 1000 Skopje, North Macedonia;
| |
Collapse
|
2
|
Palma JA. Muscarinic control of cardiovascular function in humans: a review of current clinical evidence. Clin Auton Res 2024; 34:31-44. [PMID: 38305989 PMCID: PMC10994193 DOI: 10.1007/s10286-024-01016-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 01/11/2024] [Indexed: 02/03/2024]
Abstract
PURPOSE To review the available evidence on the impact of muscarinic receptor modulation on cardiovascular control in humans. METHODS In this narrative Review we summarize data on cardiovascular endpoints from clinical trials of novel subtype-selective or quasi-selective muscarinic modulators, mostly PAMs, performed in the last decade. We also review the cardiovascular phenotype in recently described human genetic and autoimmune disorders affecting muscarinic receptors. RESULTS Recent advancements in the development of compounds that selectively target muscarinic acetylcholine receptors are expanding our knowledge about the physiological function of each muscarinic receptor subtype (M1, M2, M3, M4, M5). Among these novel compounds, positive allosteric modulators (PAMs) have emerged as the preferred therapeutic to regulate muscarinic receptor subtype function. Many muscarinic allosteric and orthosteric modulators (including but not limited to xanomeline-trospium and emraclidine) are now in clinical development and approaching regulatory approval for multiple indications, including the treatment of cognitive and psychiatric symptoms in patients with schizophrenia as well as Alzheimer's disease and other dementias. The results of these clinical trials provide an opportunity to understand the influence of muscarinic modulation on cardiovascular autonomic control in humans. While the results and the impact of each of these therapies on heart rate and blood pressure control have been variable, in part because the clinical trials were not specifically designed to measure cardiovascular endpoints, the emerging data is valuable to elucidate the relative cardiovascular contributions of each muscarinic receptor subtype. CONCLUSION Understanding the muscarinic control of cardiovascular function is of paramount importance and may contribute to the development of novel therapeutic strategies for treating cardiovascular disease.
Collapse
Affiliation(s)
- Jose-Alberto Palma
- Department of Neurology, NYU Dysautonomia Center, New York University School of Medicine, 530 First Av, Suite 9Q, New York, 10016, USA.
| |
Collapse
|
3
|
Melatonin Attenuates Dextran Sodium Sulfate Induced Colitis in Obese Mice. Pharmaceuticals (Basel) 2021; 14:ph14080822. [PMID: 34451919 PMCID: PMC8399719 DOI: 10.3390/ph14080822] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 08/16/2021] [Accepted: 08/18/2021] [Indexed: 01/03/2023] Open
Abstract
Epidemiological studies have indicated that obesity is an independent risk factor for colitis and that a high-fat diet (HFD) increases the deterioration of colitis-related indicators in mice. Melatonin has multiple anti-inflammatory effects, including inhibiting tumor growth and regulating immune defense. However, the mechanism of its activity in ameliorating obesity-promoted colitis is still unclear. This study explored the possibility that melatonin has beneficial functions in HFD-induced dextran sodium sulfate (DSS)-induced colitis in mice. Here, we revealed that HFD-promoted obesity accelerated DSS-induced colitis, while melatonin intervention improved colitis. Melatonin significantly alleviated inflammation by increasing anti-inflammatory cytokine release and reducing the levels of proinflammatory cytokines in HFD- and DSS-treated mice. Furthermore, melatonin expressed antioxidant activities and reversed intestinal barrier integrity, resulting in improved colitis in DSS-treated obese mice. We also found that melatonin could reduce the ability of inflammatory cells to utilize fatty acids and decrease the growth-promoting effect of lipids by inhibiting autophagy. Taken together, our study indicates that the inhibitory effect of melatonin on autophagy weakens the lipid-mediated prosurvival advantage, which suggests that melatonin-targeted autophagy may provide an opportunity to prevent colitis in obese individuals.
Collapse
|
4
|
Zhang S, Takahashi R, Yamashita N, Teraoka H, Kitazawa T. Αlpha 1B-adrenoceptor-mediated positive inotropic and positive chronotropic actions in the mouse atrium. Eur J Pharmacol 2018; 839:82-88. [PMID: 30172786 DOI: 10.1016/j.ejphar.2018.08.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 08/21/2018] [Accepted: 08/29/2018] [Indexed: 11/15/2022]
Abstract
Modulation of cardiac contractility by α-adrenoceptor is well known in several mammals. Mice are useful experimental animals, but α-adrenoceptor-mediated responses have been examined only in the ventricles. To determine function of α-adrenoceptors in the atrium, effects of α-adrenoceptor agonists on spontaneous contraction and electrical-field stimulation (EFS)-induced contraction were examined. In addition, expression of α1A, α1B, α1D and β1-adrenoceptor mRNAs were examined. In the right atrium, noradrenaline and phenylephrine caused positive inotropic and positive chronotropic actions. However, methoxamine, clonidine and xylazine caused positive inotropic actions, but contractile frequency was decreased at high concentrations. Phenylephrine-induced positive inotropic and chronotropic actions were partially decreased by propranolol, and both actions remained in the presence of propranolol were inhibited by phentolamine or prazosin. A low concentration of silodosin (<100 nM) did not but a high concentration (1 μM) decreased the phenylephrine-induced chronotropic actions. Negative chronotropic actions of clonidine and xylazine were insensitive to propranolol and phentolamine. The EFS-induced contraction of the left atrium was potentiated by noradrenaline, phenylephrine and methoxamine but was not changed by clonidine or xylazine. Propranolol partially decreased the actions of phenylephrine, and prazosin caused additional inhibition. Expression of β1-, α1A-, α1B- and α1D-adrenoceptor mRNAs was found in the atrium, and the expression level of β1-adrenoceptor was the highest. Of α1-adrenoceptors, the expression level of α1B was higher than that of α1A and α1D. In conclusion, α1B-adrenoceptors are expressed in the mouse atrium and mediate both positive chronotropic and inotropic actions. In contrast, the α2-adrenoceptor is not functional in the isolated atrium.
Collapse
Affiliation(s)
- Shuangyi Zhang
- Veterinary Pharmacology, Department of Veterinary Medicine, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, Japan
| | - Rena Takahashi
- Comparative Animal Pharmacology, Department of Veterinary Science, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, Japan
| | - Natsumi Yamashita
- Veterinary Pharmacology, Department of Veterinary Medicine, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, Japan
| | - Hiroki Teraoka
- Veterinary Pharmacology, Department of Veterinary Medicine, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, Japan
| | - Takio Kitazawa
- Veterinary Pharmacology, Department of Veterinary Medicine, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, Japan; Comparative Animal Pharmacology, Department of Veterinary Science, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, Japan.
| |
Collapse
|
5
|
Heijman J, Kirchner D, Kunze F, Chrétien EM, Michel-Reher MB, Voigt N, Knaut M, Michel MC, Ravens U, Dobrev D. Muscarinic type-1 receptors contribute to I K,ACh in human atrial cardiomyocytes and are upregulated in patients with chronic atrial fibrillation. Int J Cardiol 2017; 255:61-68. [PMID: 29290419 DOI: 10.1016/j.ijcard.2017.12.050] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 12/13/2017] [Accepted: 12/19/2017] [Indexed: 01/06/2023]
Abstract
BACKGROUND Basal and acetylcholine-gated inward-rectifier K+-currents (IK1 and IK,ACh, respectively) are altered in atrial fibrillation (AF). Gi-protein-coupled muscarinic (M) receptors type-2 are considered the predominant receptors activating IK,ACh. Although a role for Gq-coupled non-M2-receptor subtypes has been suggested, the precise regulation of IK,ACh by multiple M-receptor subtypes in the human atrium is unknown. Here, we investigated M1-receptor-mediated IK,ACh regulation and its remodeling in chronic AF (cAF). METHODS AND RESULTS M1-receptor mRNA and protein abundance were increased in atrial cardiomyocyte fractions and atrial homogenates from cAF patients, whereas M2-receptor levels were unchanged. The regulation of IK,ACh by M1-receptors was investigated in right-atrial cardiomyocytes using two applications of the M-receptor agonist carbachol (CCh, 2μM), with pharmacological interventions during the second application. CCh application produced a rapid current increase (Peak-IK,ACh), which declined to a quasi-steady-state level (Qss-IK,ACh). In sinus rhythm (Ctl) the selective M1-receptor antagonists pirenzepine (10nM) and muscarinic toxin-7 (MT-7, 10nM) significantly inhibited CCh-activated Peak-IK,ACh, whereas in cAF they significantly reduced both Peak- and Qss-IK,ACh, with no effects on basal inward-rectifier currents in either group. Conversely, the selective M1-receptor agonist McN-A-343 (100μM) induced a current similar to the CCh-activated current in Ctl atrial cardiomyocytes pretreated with pertussis toxin to inhibit M2-receptor-mediated Gi-protein signaling, which was abolished by MT-7. Computational modeling indicated that M1- and M2-receptors redundantly activate IK,ACh to abbreviate APD, albeit with predominant effects of M2-receptors. CONCLUSION Our data suggest that Gq-coupled M1-receptors also regulate human atrial IK,ACh and that their relative contribution to IK,ACh activation is increased in cAF patients. We provide novel insights about the role of non-M2-receptors in human atrial cardiomyocytes, which may have important implications for understanding AF pathophysiology.
Collapse
Affiliation(s)
- Jordi Heijman
- Institute of Pharmacology, West German Heart and Vascular Center, Faculty of Medicine, University Duisburg-Essen, Essen, Germany; Department of Cardiology, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands
| | - Dorit Kirchner
- Department of Pharmacology and Toxicology, Carl Gustav Carus Medical Faculty, Dresden University of Technology, Dresden, Germany
| | - Franziska Kunze
- Department of Pharmacology and Toxicology, Carl Gustav Carus Medical Faculty, Dresden University of Technology, Dresden, Germany
| | - Eva Maria Chrétien
- Department of Pharmacology and Toxicology, Carl Gustav Carus Medical Faculty, Dresden University of Technology, Dresden, Germany
| | | | - Niels Voigt
- Institute of Pharmacology, West German Heart and Vascular Center, Faculty of Medicine, University Duisburg-Essen, Essen, Germany
| | - Michael Knaut
- Heart Surgery, Heart Center Dresden, Carl Gustav Carus Medical Faculty, Dresden University of Technology, Dresden, Germany
| | - Martin C Michel
- Department of Pharmacology, Johannes Gutenberg University, Mainz, Germany
| | - Ursula Ravens
- Department of Pharmacology and Toxicology, Carl Gustav Carus Medical Faculty, Dresden University of Technology, Dresden, Germany; Institute of Experimental Cardiovascular Medicine, University Heart Center Freiburg-Bad Krozingen, Freiburg, Germany
| | - Dobromir Dobrev
- Institute of Pharmacology, West German Heart and Vascular Center, Faculty of Medicine, University Duisburg-Essen, Essen, Germany; Department of Pharmacology and Toxicology, Carl Gustav Carus Medical Faculty, Dresden University of Technology, Dresden, Germany.
| |
Collapse
|
6
|
Caldenhove S, Borghans L, Blokland A, Sambeth A. Role of acetylcholine and serotonin in novelty processing using an oddball paradigm. Behav Brain Res 2017; 331:199-204. [DOI: 10.1016/j.bbr.2017.05.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 05/09/2017] [Accepted: 05/10/2017] [Indexed: 12/28/2022]
|
7
|
Borghans LGJM, Blokland A, Sambeth A. Effects of biperiden and acute tryptophan depletion and their combination on verbal word memory and EEG. Psychopharmacology (Berl) 2017; 234:1135-1143. [PMID: 28210777 PMCID: PMC5352740 DOI: 10.1007/s00213-017-4549-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 01/25/2017] [Indexed: 12/22/2022]
Abstract
BACKGROUND Research on the neurobiological foundations of memory has shown that multiple neurotransmitters play an important role in memory processing. To study the interaction between neurotransmitters such as acetylcholine and serotonin, pharmacological models can be used. In this study, we tested the effects of the muscarinic M1 antagonist biperiden, acute tryptophan depletion (ATD), and the interaction between the two on episodic memory using the verbal learning task. METHODS The study was conducted according to a double-blind, placebo-controlled, four-way crossover design. Seventeen participants received biperiden (2.0 mg), ATD (SolugelP), a combination of both, or a placebo in counterbalanced order with a wash out of at least 7 days. A verbal learning task was performed while recording electroencephalography. The task consisted of an immediate and delayed recall as well as a recognition part. RESULTS Results revealed decreased scores on the delayed recall after biperiden and ATD separately but no significant interaction between the two. However, the event-related potential components P3b, N400, and P600 did show an interaction during encoding. CONCLUSION These results indicate that both BIP and ATD impair episodic memory. However, an interaction between the serotonergic and cholinergic system on memory performance is not supported.
Collapse
Affiliation(s)
- Laura G J M Borghans
- Faculty of Psychology and Neuroscience, Department of Neuropsychology and Psychopharmacology, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands.
| | - Arjan Blokland
- Faculty of Psychology and Neuroscience, Department of Neuropsychology and Psychopharmacology, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
| | - Anke Sambeth
- Faculty of Psychology and Neuroscience, Department of Neuropsychology and Psychopharmacology, Maastricht University, PO Box 616, 6200 MD, Maastricht, The Netherlands
| |
Collapse
|
8
|
Soukup O, Winder M, Killi UK, Wsol V, Jun D, Kuca K, Tobin G. Acetylcholinesterase Inhibitors and Drugs Acting on Muscarinic Receptors- Potential Crosstalk of Cholinergic Mechanisms During Pharmacological Treatment. Curr Neuropharmacol 2017; 15:637-653. [PMID: 27281175 PMCID: PMC5543679 DOI: 10.2174/1570159x14666160607212615] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2016] [Revised: 04/28/2016] [Accepted: 05/31/2016] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Pharmaceuticals with targets in the cholinergic transmission have been used for decades and are still fundamental treatments in many diseases and conditions today. Both the transmission and the effects of the somatomotoric and the parasympathetic nervous systems may be targeted by such treatments. Irrespective of the knowledge that the effects of neuronal signalling in the nervous systems may include a number of different receptor subtypes of both the nicotinic and the muscarinic receptors, this complexity is generally overlooked when assessing the mechanisms of action of pharmaceuticals. METHODS We have search of bibliographic databases for peer-reviewed research literature focused on the cholinergic system. Also, we have taken advantage of our expertise in this field to deduce the conclusions of this study. RESULTS Presently, the life cycle of acetylcholine, muscarinic receptors and their effects are reviewed in the major organ systems of the body. Neuronal and non-neuronal sources of acetylcholine are elucidated. Examples of pharmaceuticals, in particular cholinesterase inhibitors, affecting these systems are discussed. The review focuses on salivary glands, the respiratory tract and the lower urinary tract, since the complexity of the interplay of different muscarinic receptor subtypes is of significance for physiological, pharmacological and toxicological effects in these organs. CONCLUSION Most pharmaceuticals targeting muscarinic receptors are employed at such large doses that no selectivity can be expected. However, some differences in the adverse effect profile of muscarinic antagonists may still be explained by the variation of expression of muscarinic receptor subtypes in different organs. However, a complex pattern of interactions between muscarinic receptor subtypes occurs and needs to be considered when searching for selective pharmaceuticals. In the development of new entities for the treatment of for instance pesticide intoxication, the muscarinic receptor selectivity needs to be considered. Reactivators generally have a muscarinic M2 receptor acting profile. Such a blockade may engrave the situation since it may enlarge the effect of the muscarinic M3 receptor effect. This may explain why respiratory arrest is the major cause for deaths by esterase blocking.
Collapse
Affiliation(s)
- Ondrej Soukup
- Department of Toxicology and Military Pharmacy, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic
- Biomedical Research Centre, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
- National Institute of Mental Health, Klecany, Hradec Kralove, Czech Republic
| | - Michael Winder
- Institute of Neuroscience and Physiology, Department of Pharmacology, the Sahlgrenska Academy at the University of Gothenburg, Sweden
| | - Uday Kumar Killi
- Department of Biochemical Sciences, Faculty of Pharmacy, Charles University, Hradec Kralove, Czech Republic
| | - Vladimir Wsol
- Department of Biochemical Sciences, Faculty of Pharmacy, Charles University, Hradec Kralove, Czech Republic
| | - Daniel Jun
- Department of Toxicology and Military Pharmacy, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic
- Biomedical Research Centre, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
| | - Kamil Kuca
- Biomedical Research Centre, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
| | - Gunnar Tobin
- Institute of Neuroscience and Physiology, Department of Pharmacology, the Sahlgrenska Academy at the University of Gothenburg, Sweden
| |
Collapse
|
9
|
Harada N, Ochi K, Yaosaka N, Teraoka H, Hiraga T, Iwanaga T, Unno T, Komori S, Yamada M, Kitazawa T. Immunohistochemical and functional studies for M3muscarinic receptors and cyclo-oxygenase-2 expressed in the mouse atrium. ACTA ACUST UNITED AC 2012; 32:41-52. [DOI: 10.1111/j.1474-8673.2012.00472.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Revised: 03/08/2012] [Accepted: 04/15/2012] [Indexed: 11/30/2022]
Affiliation(s)
- N. Harada
- Department of Veterinary Medicine; Rakuno Gakuen University; Ebetsu; Hokkaido; 069-8501; Japan
| | - K. Ochi
- Department of Veterinary Medicine; Rakuno Gakuen University; Ebetsu; Hokkaido; 069-8501; Japan
| | - N. Yaosaka
- Department of Veterinary Science; Rakuno Gakuen University; Ebetsu; Hokkaido; 069-8501; Japan
| | - H. Teraoka
- Department of Veterinary Medicine; Rakuno Gakuen University; Ebetsu; Hokkaido; 069-8501; Japan
| | - T. Hiraga
- Department of Veterinary Medicine; Rakuno Gakuen University; Ebetsu; Hokkaido; 069-8501; Japan
| | - T. Iwanaga
- Department of Functional Morphology, Laboratory of Histology and Cytology; Hokkaido University Graduate School of Medicine; Sapporo; 060-8638; Japan
| | - T. Unno
- Laboratory of Pharmacology, Faculty of Applied Biological Science; Gifu University; Gifu; 501-1193; Japan
| | - S. Komori
- Laboratory of Pharmacology, Faculty of Applied Biological Science; Gifu University; Gifu; 501-1193; Japan
| | - M. Yamada
- Common Resources Group; Okinawa Institute of Science and Technology; Okinawa; 904-0411; Japan
| | | |
Collapse
|
10
|
Mazzadi AN, Pineau J, Costes N, Le Bars D, Bonnefoi F, Croisille P, Porcher R, Chevalier P. Muscarinic receptor upregulation in patients with myocardial infarction: a new paradigm. Circ Cardiovasc Imaging 2009; 2:365-72. [PMID: 19808624 DOI: 10.1161/circimaging.108.822106] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
BACKGROUND Despite the major role attributed to myocardial vagal activity in left ventricular arrhythmogenesis in chronic myocardial infarction, the impact of infarction on left ventricular muscarinic receptor density remains unknown. METHODS AND RESULTS Left ventricular muscarinic receptor density was measured in vivo by positron emission tomography using the specific antagonist [(11)C]methylquinuclidinyl benzilate ([(11)C]MQNB) in 11 patients 43+/-20 days after myocardial infarction and 9 healthy volunteers. The extent of myocardial damage was quantified by delayed contrast-enhanced MRI. Three short-axis slices from each subject were analyzed in matched positron emission tomography and MRI images. A 2-injection positron emission tomography protocol was used; [(11)C]MQNB time-activity curves were obtained in 6 regions per slice and fitted to a 3-compartment ligand-receptor model. Four classes of myocardial regions were considered: normal (in volunteers); remote, supplied by healthy or <70% diameter reduction arteries and without MRI signs of damage; potentially damaged, supplied by infarct-related or >70% diameter reduction arteries and without signs of damage; and damaged, with damage. The muscarinic receptor density in remote (67+/-30 pmol/mL tissue; n=86) and potentially damaged (71+/-30 pmol/mL tissue; n=42) regions of patients was higher than in normal regions of volunteers (32+/-17 pmol/mL tissue; n=156; P<0.001). The muscarinic receptor density in damaged regions (42+/-21 pmol/mL tissue; n=58) was reduced compared with remote and potentially damaged regions (P<0.001) but was not significantly different from normal regions in volunteers (P=0.093). CONCLUSIONS Vagal control in patients with chronic myocardial infarction involves muscarinic receptor upregulation in remote nondamaged left ventricular regions. Our results suggest that the receptor density remains within normal values in myocardial regions containing damaged tissue.
Collapse
|
11
|
Peraza-Cruces K, Gutiérrez-Guédez L, Castañeda Perozo D, Lankford CR, Rodríguez-Bonfante C, Bonfante-Cabarcas R. Trypanosoma cruzi infection induces up-regulation of cardiac muscarinic acetylcholine receptors in vivo and in vitro. Braz J Med Biol Res 2009; 41:796-803. [PMID: 18820770 DOI: 10.1590/s0100-879x2008000900009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2007] [Accepted: 08/27/2008] [Indexed: 11/22/2022] Open
Abstract
The pathogenesis of chagasic cardiomyopathy is not completely understood, but it has been correlated with parasympathetic denervation (neurogenic theory) and inflammatory activity (immunogenic theory) that could affect heart muscarinic acetylcholine receptor (mAChR) expression. In order to further understand whether neurogenic and/or immunogenic alterations are related to changes in mAChR expression, we studied two models of Trypanosoma cruzi infection: 1) in 3-week-old male Sprague Dawley rats chronically infected with T. cruzi and 2) isolated primary cardiomyocytes co-cultured with T. cruzi and peripheral blood mononuclear cells (PBMC). Using [3H]-quinuclidinylbenzilate ([3H]-QNB) binding assays, we evaluated mAChR expression in homogenates from selected cardiac regions, PBMC, and cultured cardiomyocytes. We also determined in vitro protein expression and pro-inflammatory cytokine expression in serum and cell culture medium by ELISA. Our results showed that: 1) mAChR were significantly (P < 0.05) up-regulated in right ventricular myocardium (means +/- SEM; control: 58.69 +/- 5.54, N = 29; Chagas: 72.29 +/- 5.79 fmol/mg, N = 34) and PBMC (control: 12.88 +/- 2.45, N = 18; Chagas: 20.22 +/- 1.82 fmol/mg, N = 19), as well as in cardiomyocyte transmembranes cultured with either PBMC/T. cruzi co-cultures (control: 24.33 +/- 3.83; Chagas: 43.62 +/- 5.08 fmol/mg, N = 7 for both) or their conditioned medium (control: 37.84 +/- 3.84, N = 4; Chagas: 54.38 +/- 6.28 fmol/mg, N = 20); 2) [(3)H]-leucine uptake was increased in cardiomyocytes co-cultured with PBMC/T. cruzi-conditioned medium (Chagas: 21,030 +/- 2321; control 10,940 +/- 2385 dpm, N = 7 for both; P < 0.05); 3) plasma IL-6 was increased in chagasic rats, IL-1beta, was increased in both plasma of chagasic rats and in the culture medium, and TNF-alpha level was decreased in the culture medium. In conclusion, our results suggest that cytokines are involved in the up-regulation of mAChR in chronic Chagas disease.
Collapse
Affiliation(s)
- K Peraza-Cruces
- Unidad de Bioquímica, Universidad Centro Occidental "Lisandro Alvarado", Barquisimeto, Venezuela
| | | | | | | | | | | |
Collapse
|
12
|
Kitazawa T, Asakawa K, Nakamura T, Teraoka H, Unno T, Komori SI, Yamada M, Wess J. M3 muscarinic receptors mediate positive inotropic responses in mouse atria: a study with muscarinic receptor knockout mice. J Pharmacol Exp Ther 2009; 330:487-93. [PMID: 19429792 DOI: 10.1124/jpet.109.153304] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The potential functional roles of M(3) muscarinic receptors in mouse atria were examined by pharmacological and molecular biological techniques, using wild-type mice, muscarinic M(2) or M(3) receptor single knockout (M(2)KO, M(3)KO), and M(2) and M(3) muscarinic receptor double knockout mice (M(2)/M(3)KO). Real-time quantitative reverse transcriptase-polymerase chain reaction analysis showed that the M(2) receptor mRNA was expressed predominantly in mouse atria but that the M(1), M(3), M(4), and M(5) receptor subtypes were also expressed at low levels. Carbachol (10 nM-30 microM) decreased the spontaneous beating frequency of right atria isolated from wild-type mice. Studies with subtype-preferring antagonists and atria from M(2)KO mice confirmed that this activity is mediated by the M(2) receptor subtype. In left atria from wild-type mice, carbachol decreased the amplitude of electrical field stimulation-evoked contractions (negative inotropic action), but this inhibition was transient and was followed by a gradual increase in contraction amplitude (positive inotropic response). In atria from M(3)KO mice, the transient negative inotropic action of carbachol changed to a sustained negative inotropic action. In contrast, in atria from M(2)KO mice, carbachol showed only positive inotropic activity. In atria from M(2)/M(3) double KO mice, carbachol was devoid of any inotropic activity. These observations, complemented by functional studies with subtype-preferring antagonists, convincingly demonstrate that atrial M(3) muscarinic receptors mediate positive inotropic effects in mouse atria. Physiologically, this activity may serve to dampen the inhibitory effects of M(2) receptor activation on atrial contractility.
Collapse
Affiliation(s)
- Takio Kitazawa
- Department of Pharmacology, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, Japan.
| | | | | | | | | | | | | | | |
Collapse
|
13
|
The detection of the non-M2 muscarinic receptor subtype in the rat heart atria and ventricles. Naunyn Schmiedebergs Arch Pharmacol 2008; 378:103-16. [PMID: 18443764 DOI: 10.1007/s00210-008-0285-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2004] [Accepted: 03/17/2008] [Indexed: 10/22/2022]
Abstract
Mammal heart tissue has long been assumed to be the exclusive domain of the M(2) subtype of muscarinic receptor, but data supporting the presence of other subtypes also exist. We have tested the hypothesis that muscarinic receptors other than the M(2) subtype are present in the heart as minor populations. We used several approaches: a set of competition binding experiments with pirenzepine, AFDX-116, 4-DAMP, PD 102807, p-F-HHSiD, AQ-RA 741, DAU 5884, methoctramine and tripinamide, blockage of M(1) muscarinic receptors using MT7 toxin, subtype-specific immunoprecipitation experiments and determination of phospholipase C activity. We also attempted to block M(1)-M(4) receptors using co-treatment with MT7 and AQ-RA 741. Our results show that only the M(2) subtype is present in the atria. In the ventricles, however, we were able to determine that 20% (on average) of the muscarinic receptors were subtypes other than M(2), with the majority of these belonging to the M(1) subtype. We were also able to detect a marginal fraction (6 +/- 2%) of receptors that, based on other findings, belong mainly to the M(5) muscarinic receptors. Co-treatment with MT7 and AQ-RA 741 was not a suitable tool for blocking of M(1)-M(4) receptors and can not therefore be used as a method for M(5) muscarinic receptor detection in substitution to crude venom. These results provide further evidence of the expression of the M(1) muscarinic receptor subtype in the rat heart and also show that the heart contains at least one other, albeit minor, muscarinic receptor population, which most likely belongs to the M(5) muscarinic receptors but not to that of the M(3) receptors.
Collapse
|
14
|
Osadchii OE. Subtype-selective blockade of cardiac muscarinic receptors inhibits vagal chronotropic responses in cats. Pflugers Arch 2007; 455:819-28. [PMID: 17899166 DOI: 10.1007/s00424-007-0347-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2007] [Revised: 07/29/2007] [Accepted: 09/05/2007] [Indexed: 10/22/2022]
Abstract
This study was designed to determine if chronotropic responses induced by neurally released acetylcholine are modified by subtype-selective blockade of cardiac muscarinic cholinoreceptors. In anesthetized cats, a single burst of vagal stimulation was generated with an incremental time delay after the P wave of the atrial electrogram (P-Stimulus interval). The slope of the relationships between P-Stimulus and P-P intervals was used to assess changes in responsiveness of cardiac pacemaker to vagal effects throughout the cardiac cycle. An increase in P-Stimulus interval over the initial portion (approximately 120 ms) of the cardiac cycle produced a significant increment in lengthening of the P-P interval. Once the maximal negative chronotropic response was achieved, a further increase in P-Stimulus interval by only approximately 25 ms resulted in profound (by 80-90%) reductions in vagal effects, thus yielding a bimodal vagal phase response curve. Antagonists of M1 (pirenzepine), M2 (methoctramine and gallamine), and M3 (4-DAMP) muscarinic cholinoreceptors produced a reduction in the magnitude of maximal lengthening of cardiac cycle as well as an increase in latency of vagal effects. However, the increment in prolongation of P-P interval induced by a given change in timing of vagal stimulation during cardiac cycle was reduced by M1 and M2 muscarinic receptor blockers, but was unaffected by 4-DAMP. None of the antagonists modified the range of P-Stimulus intervals over which the maximum-to-minimum change of vagal responses occurred. Taken together, these data suggest different contribution of various subtypes of cardiac muscarinic receptors into the negative chronotropic responses induced by brief bursts of vagal stimulation.
Collapse
Affiliation(s)
- Oleg E Osadchii
- Normal Physiology Department, Kuban Medical Academy, Krasnodar, Russia.
| |
Collapse
|