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Omara AF, Elzohry AA, Abdelrahman AF. Comparison of Caudal Block and Dexmedetomidine Infusion in Pediatric Patients Undergoing Hypospadias Repair Surgery: A Prospective, Randomized, Double-blinded Clinical Study. Anesth Pain Med 2023; 13:e130623. [PMID: 37489170 PMCID: PMC10363365 DOI: 10.5812/aapm-130623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 01/08/2023] [Accepted: 01/09/2023] [Indexed: 07/26/2023] Open
Abstract
Background Many parents continue to reject caudal block since they worry about a rare neurological consequence that may happen. A parenteral surrogate is sought because it can induce recovery with features such as local analgesia. Objectives To compare the efficacy and safety of intravenous dexmedetomidine versus caudal and general anesthesia (GA) in children undergoing hypospadias surgery repair. Methods A randomized prospective study was conducted on 135 pediatric patients scheduled for hypospadias repair surgery in the hospital affiliated to Tanta University. The participants were divided into a control group (Group C) receiving GA, a caudal group receiving caudal block after GA, and a dexmedetomidine group (Group D) receiving intravenous dexmedetomidine after GA. The postoperative modified objective pain score (MOPS), the total pethidine received in the first 24 h postoperatively, and complications were recorded. Results The patients receiving GA required a significantly higher pethidine dose than the other two groups without a significant difference between caudal and dexmedetomidine. The patients receiving dexmedetomidine were extubated significantly later than patients in the other two groups. Regarding the MOPS score, there was a significant difference between Group C and the other two groups 30 minutes and one hour after operation regarding movements, posture, and agitation. Moreover, a significantly larger number of patients developed tachycardia in Group C compared to the other groups. Conclusions With the caudal block, the benefits of smooth emergency can be obtained by intravenous dexmedetomidine; however, it had less analgesic efficacy in the pediatric patients undergoing hypospadias repair surgery.
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Affiliation(s)
- Amany Faheem Omara
- Department of Anaesthesia and Surgical Intensive Care, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Alaa Ali Elzohry
- Department of Anaesthesia, ICU and Pain Relief, South Egypt Cancer Institute, Assiut University, Assiut, Egypt
| | - Ahmed Fetouh Abdelrahman
- Department of Anaesthesia and Surgical Intensive Care, Faculty of Medicine, Tanta University, Tanta, Egypt
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Bousquet P, Hudson A, García-Sevilla JA, Li JX. Imidazoline Receptor System: The Past, the Present, and the Future. Pharmacol Rev 2020; 72:50-79. [PMID: 31819014 DOI: 10.1124/pr.118.016311] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Imidazoline receptors historically referred to a family of nonadrenergic binding sites that recognize compounds with an imidazoline moiety, although this has proven to be an oversimplification. For example, none of the proposed endogenous ligands for imidazoline receptors contain an imidazoline moiety but they are diverse in their chemical structure. Three receptor subtypes (I1, I2, and I3) have been proposed and the understanding of each has seen differing progress over the decades. I1 receptors partially mediate the central hypotensive effects of clonidine-like drugs. Moxonidine and rilmenidine have better therapeutic profiles (fewer side effects) than clonidine as antihypertensive drugs, thought to be due to their higher I1/α 2-adrenoceptor selectivity. Newer I1 receptor agonists such as LNP599 [3-chloro-2-methyl-phenyl)-(4-methyl-4,5-dihydro-3H-pyrrol-2-yl)-amine hydrochloride] have little to no activity on α 2-adrenoceptors and demonstrate promising therapeutic potential for hypertension and metabolic syndrome. I2 receptors associate with several distinct proteins, but the identities of these proteins remain elusive. I2 receptor agonists have demonstrated various centrally mediated effects including antinociception and neuroprotection. A new I2 receptor agonist, CR4056 [2-phenyl-6-(1H-imidazol-1yl) quinazoline], demonstrated clear analgesic activity in a recently completed phase II clinical trial and holds great promise as a novel I2 receptor-based first-in-class nonopioid analgesic. The understanding of I3 receptors is relatively limited. Existing data suggest that I3 receptors may represent a binding site at the Kir6.2-subtype ATP-sensitive potassium channels in pancreatic β-cells and may be involved in insulin secretion. Despite the elusive nature of their molecular identities, recent progress on drug discovery targeting imidazoline receptors (I1 and I2) demonstrates the exciting potential of these compounds to elicit neuroprotection and to treat various disorders such as hypertension, metabolic syndrome, and chronic pain.
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Affiliation(s)
- Pascal Bousquet
- Faculty of Medicine, University of Strasbourg, Strasbourg, France (P.B.); Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada (A.H.); Laboratory of Neuropharmacology, University Research Institute on Health Sciences, University of the Balearic Islands, Palma de Malllorca, Spain (J.A.G.-S.); and Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, New York (J.-X.L.)
| | - Alan Hudson
- Faculty of Medicine, University of Strasbourg, Strasbourg, France (P.B.); Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada (A.H.); Laboratory of Neuropharmacology, University Research Institute on Health Sciences, University of the Balearic Islands, Palma de Malllorca, Spain (J.A.G.-S.); and Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, New York (J.-X.L.)
| | - Jesús A García-Sevilla
- Faculty of Medicine, University of Strasbourg, Strasbourg, France (P.B.); Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada (A.H.); Laboratory of Neuropharmacology, University Research Institute on Health Sciences, University of the Balearic Islands, Palma de Malllorca, Spain (J.A.G.-S.); and Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, New York (J.-X.L.)
| | - Jun-Xu Li
- Faculty of Medicine, University of Strasbourg, Strasbourg, France (P.B.); Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada (A.H.); Laboratory of Neuropharmacology, University Research Institute on Health Sciences, University of the Balearic Islands, Palma de Malllorca, Spain (J.A.G.-S.); and Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, New York (J.-X.L.)
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Ibrahim MS, Samuel B, Mohamed W, Suchdev K. Cardiac Dysfunction in Neurocritical Care: An Autonomic Perspective. Neurocrit Care 2020; 30:508-521. [PMID: 30484009 DOI: 10.1007/s12028-018-0636-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A number of neurologic disorders can cause cardiac dysfunction by involving the conductive system and contractile apparatus of the heart. This is especially prominent in the neurocritical care setting where the spectrum of cardiac dysfunction due to acute neurologic injury ranges from trivial and isolated electrocardiographic changes to malignant arrhythmias and sudden death (Table 1). The mechanism of these cardiac complications is complex and not fully understood. An understanding of the neuroanatomical structures and pathways is of immense importance to comprehend the underlying pathophysiology that culminates as cardiac damage and dysregulation. Once the process is initiated, it can complicate and adversely affect the outcome of primary neurologic conditions commonly seen in the neurocritical care setting. Not only are these cardiac disorders under-recognized, there is a paucity of data to formulate evidence-based guidelines regarding early detection, acute management, and preventive strategies. However, certain details of clinical features and their course combined with location of primary neurologic lesion on neuroimaging and data obtained from laboratory investigations can be of great value to develop a strategy to appropriately manage these patients and to prevent adverse outcome from these cardiac complications. In this review, we highlight the mechanisms of cardiac dysfunction due to catastrophic neurologic conditions or due to stress of critical illness. We also address various clinical syndromes of cardiac dysfunction that occur as a result of the neurologic illness and in turn may complicate the course of the primary neurologic condition.
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Affiliation(s)
- Mohammad S Ibrahim
- Department of Neurology, Division of Neurocritical care, Wayne State University School of Medicine, Detroit, MI, USA
| | - Bennson Samuel
- Department of Neurology, Division of Neurocritical care, Wayne State University School of Medicine, Detroit, MI, USA
| | - Wazim Mohamed
- Department of Neurology, Division of Neurocritical care, Wayne State University School of Medicine, Detroit, MI, USA
| | - Kushak Suchdev
- Department of Neurology, Division of Neurocritical care, Wayne State University School of Medicine, Detroit, MI, USA.
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Joviano-Santos JV, Santos-Miranda A, Joca HC, Cruz JS, Ferreira AJ. Diminazene aceturate (DIZE) has cellular and in vivo antiarrhythmic effects. Clin Exp Pharmacol Physiol 2019; 47:213-219. [PMID: 31643111 DOI: 10.1111/1440-1681.13200] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 10/14/2019] [Accepted: 10/15/2019] [Indexed: 01/13/2023]
Abstract
Diminazene aceturate (DIZE) is an anti-protozoan compound that has been previously reported to increase the activity of the angiotensin-converting enzyme 2 (ACE2) and thus increase Angiotensin-(1-7) production, leading to cardioprotection against post-myocardial infarction dysfunction and structural remodelling. Moreover, DIZE is able to ameliorate morpho-functional changes after myocardial infarction by enhancing ACE2 activity, thus increasing Angiotensin-(1-7) production (a benefic peptide of the renin-angiotensin system). However, despite the improvement in cardiac function/structure, little is known about DIZE effects on arrhythmia suppression, contraction/excitable aspects of the heart and importantly its mechanisms of action. Thus, our aim was to test the acute effect of DIZE cardioprotection at the specific level of potential antiarrhythmic effects and modulation in excitation-contraction coupling. For this, we performed in vitro and in vivo techniques for arrhythmia induction followed by an acute administration of DIZE. For the first time, we described that DIZE can reduce arrhythmias which is explained by modulation of cardiomyocyte contraction and excitability. Such effects were independent of Mas receptor and nitric oxide release. Development of a new DIZE-based approach to ameliorate myocardial contractile and electrophysiological dysfunction requires further investigation; however, DIZE may provide the basis for a future beneficial therapy to post-myocardial infarction patients.
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Affiliation(s)
- Julliane V Joviano-Santos
- Department of Morphology, Institute of Biological Sciences, Federal University of Minas, Gerais, Brazil
| | - Artur Santos-Miranda
- Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas, Gerais, Brazil
| | - Humberto C Joca
- Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas, Gerais, Brazil
| | - Jader S Cruz
- Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas, Gerais, Brazil
| | - Anderson J Ferreira
- Department of Morphology, Institute of Biological Sciences, Federal University of Minas, Gerais, Brazil
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Joviano-Santos JV, Santos-Miranda A, Joca HC, Cruz JS, Ferreira AJ. New insights into the elucidation of angiotensin-(1-7) in vivo antiarrhythmic effects and its related cellular mechanisms. Exp Physiol 2016; 101:1506-1516. [PMID: 27730696 DOI: 10.1113/ep085884] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 10/05/2016] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? Recently, there have been many studies exploring the biological effects of angiotensin-(1-7), which has been proved to have cardioprotective actions. However, the effects of this peptide on cardiac arrhythmias in vivo and details regarding its mechanism of action are still undetermined. What is the main finding and its importance? We investigated protective effects of angiotensin-(1-7) on cardiac arrhythmias in vivo, which were not properly explored in terms of cellular mechanisms. To verify effects of angiotensin-(1-7), we used different but complementary experimental approaches. Our data provide new evidence on the cellular mechanism and an in vivo demonstration of the acute antiarrhythmic effect of angiotensin-(1-7). Angiotensin-(1-7) [Ang-(1-7)] has been proved to have cardioprotective effects. However, the effects of this peptide on cardiac arrhythmias in vivo and details regarding its mechanism of action are still undetermined. The aim of this study was to investigate the protective effects of Ang-(1-7) against cardiac arrhythmias, its in vivo effects and cellular mechanism of action. We analysed the ECG upon inducement of arrhythmias in vivo in rats using a combination of halothane and adrenaline. To analyse the effects of Ang-(1-7) on cells, fresh mouse ventricular cardiomyocytes were isolated. The cardiomyocytes were superfused with a solution containing halothane and isoprenaline as a model to induce arrhythmias and used in three different approaches, namely a contractility assay, patch-clamp technique and confocal microscopy. The in vivo ECG showed that the injection of Ang-(1-7) (4 nm i.v.) significantly reduced cardiac arrhythmias [before, 49 ± 43 arrhythmic events versus after Ang-(1-7), 16 ± 14 arrhythmic events]. This effect was blocked by injection of A-779 and l-NAME, without changes in haemodynamic parameters. In addition, contractility experiments showed that Ang-(1-7) significantly decreased the number of arrhythmic events without changing the fractional shortening. This protection was associated with a reduction of the action potential repolarization and membrane hyperpolarization. Moreover, Ang-(1-7) decreased the number of calcium waves without any changes in the amplitude of the calcium transient, despite a significant reduction in the decay rate. Our data provide new evidence on the cellular mechanism together with an in vivo demonstration of the antiarrhythmic effects of Ang-(1-7).
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Affiliation(s)
| | - Artur Santos-Miranda
- Department of Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Humberto Cavalcante Joca
- Department of Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Jader Santos Cruz
- Department of Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Anderson José Ferreira
- Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
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Song IA, Seo KS, Oh AY, Baik JS, Kim JH, Hwang JW, Jeon YT. Dexmedetomidine Injection during Strabismus Surgery Reduces Emergence Agitation without Increasing the Oculocardiac Reflex in Children: A Randomized Controlled Trial. PLoS One 2016; 11:e0162785. [PMID: 27617832 PMCID: PMC5019399 DOI: 10.1371/journal.pone.0162785] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 08/26/2016] [Indexed: 11/19/2022] Open
Abstract
Objective Dexmedetomidine is known to reduce the incidence of emergence agitation, which is a common complication after inhalational anesthesia like sevoflurane or desflurane in children. However, the dose of dexmedetomidine used for this purpose is reported variously and the most effective dose is not known. In this study, we tried to find the most effective dose of dexmedetomidine to reduce the incidence of emergence agitation in children undergoing strabismus surgery without the complications like oculocardiac reflex (OCR) or postoperative vomiting. Methods We randomized 103 pediatric patients aged 2–6 years and undergoing elective strabismus surgery into four groups. Anesthesia was induced with sevoflurane and maintained with desflurane. At the start of induction, dexmedetomidine, delivered at 0.25, 0.5, or 1 μg/kg, or saline was infused intravenously in the D0.25, D0.5, D1 groups, respectively. The primary outcome measure was the incidence of emergence agitation and the secondary outcome measure was the incidence of intraoperative OCR, postoperative vomiting, and desaturation events. Results The incidence of emergence agitation was 60, 48, 44, and 21% (P = 0.005) and the incidence of intraoperative OCR was 36, 36, 36, and 37% (P = 0.988) in the control, D0.25, D0.5, and D1 groups, respectively. And, postoperative vomiting rate and desaturation events were low in the all groups. Conclusion Dexmedetomidine decreased the incidence of emergence agitation without increasing intraoperative oculocardiac reflex. Dexmedetomidine delivered at 1 μg/kg was more effective at reducing emergence agitation than lower doses in children undergoing strabismus surgery under desflurane anesthesia. Trial Registration Clinical Research Information Service KCT0000141
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Affiliation(s)
- In-Ae Song
- Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Kwang-Suk Seo
- Department of Dental Anesthesiology, Seoul National University School of Dentistry, Seoul, Korea
| | - Ah-Young Oh
- Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
- Department of Anesthesiology and Pain Medicine, Seoul National University College of Medicine, Seoul, Korea
- * E-mail:
| | - Ji-Seok Baik
- Department of Anesthesiology and Pain Medicine, Pusan National University Hospital, Busan, Korea
| | - Jin Hee Kim
- Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
- Department of Anesthesiology and Pain Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Jung- Won Hwang
- Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
- Department of Anesthesiology and Pain Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Young-Tae Jeon
- Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
- Department of Anesthesiology and Pain Medicine, Seoul National University College of Medicine, Seoul, Korea
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Chrysostomou C, Sanchez-de-Toledo J, Wearden P, Jooste EH, Lichtenstein SE, Callahan PM, Suresh T, O'Malley E, Shiderly D, Haney J, Yoshida M, Orr R, Munoz R, Morell VO. Perioperative use of dexmedetomidine is associated with decreased incidence of ventricular and supraventricular tachyarrhythmias after congenital cardiac operations. Ann Thorac Surg 2011; 92:964-72; discussion 972. [PMID: 21871284 DOI: 10.1016/j.athoracsur.2011.04.099] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Revised: 04/01/2011] [Accepted: 04/06/2011] [Indexed: 11/16/2022]
Abstract
BACKGROUND Postoperative tachyarrhythmias remain a common complication after congenital cardiac operations. Dexmedetomidine (DEX), an α-2 adrenoreceptor agonist, can have a therapeutic role in supraventricular tachyarrhythmias for cardioversion to sinus rhythm or heart rate control. Whether routine perioperative use of DEX decreases the incidence of supraventricular and ventricular tachyarrhythmias was studied. METHODS In this prospective cohort study, 32 pediatric patients undergoing cardiothoracic operations received DEX and were compared with 20 control patients who did not receive DEX. RESULTS Dexmedetomidine was started after anesthesia induction and continued intraoperatively and postoperatively for 38±4 hours (mean dose, 0.76±0.04 μg/kg/h). Ten control patients and 2 DEX patients sustained 16 episodes of tachyarrhythmias (p=0.001), including a 25% vs 0% (p=0.01) incidence of ventricular tachycardia and 25% vs 6% (p=0.05) of supraventricular arrhythmias in the control and DEX group, respectively. Transient complete heart block occurred in 2 control patients and in 1 DEX patient. Control patients had a higher heart rate (141±5 vs 127±3 beats/min, p=0.03), more sinus tachycardia episodes (40% vs 6%; p=0.008), required more antihypertensive drugs with nitroprusside (20±7 vs 4±1 μg/kg; p=0.004) and nicardipine (13±5 vs 2±1 μg/kg; p=0.02), and required more fentanyl (39±8 vs 19±3 μg/kg; p=0.005). CONCLUSIONS Perioperative use of dexmedetomidine is associated with a significantly decreased incidence of ventricular and supraventricular tachyarrhythmias, without significant adverse effects.
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Affiliation(s)
- Constantinos Chrysostomou
- Department of Critical Care Medicine, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15224, USA.
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Activation of phosphatidylinositol 3-kinase/Akt signaling pathway and endogenous nitric oxide are needed for the antiarrhythmic effect of centrally administered rilmenidine. Eur J Pharmacol 2010; 647:155-60. [DOI: 10.1016/j.ejphar.2010.08.035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2010] [Revised: 07/13/2010] [Accepted: 08/24/2010] [Indexed: 11/18/2022]
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Chrysostomou C, Beerman L, Shiderly D, Berry D, Morell VO, Munoz R. Dexmedetomidine: A Novel Drug for the Treatment of Atrial and Junctional Tachyarrhythmias During the Perioperative Period for Congenital Cardiac Surgery: A Preliminary Study. Anesth Analg 2008; 107:1514-22. [DOI: 10.1213/ane.0b013e318186499c] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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The antiarrhythmic effect of centrally administered rilmenidine involves muscarinic receptors, protein kinase C and mitochondrial signalling pathways. Br J Pharmacol 2008; 153:1623-30. [PMID: 18297108 DOI: 10.1038/bjp.2008.35] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND AND PURPOSE We have previously demonstrated that stimulation of imidazoline receptors in the CNS prevented halothane-adrenaline arrhythmias during halothane anaesthesia and that stimulation of the vagus nerve may be critical to this effect. However, details of the mechanism(s) involved are not yet available. The present study was designed to examine the role of muscarinic receptors, protein kinase C (PKC), ATP-sensitive potassium channels (K(ATP)) and the mitochondrial permeability transition pore (MPTP) in the antiarrhythmic effect of rilmenidine, an imidazoline receptor agonist. EXPERIMENTAL APPROACH Rats were anaesthetized with halothane and monitored continuously for arterial blood pressure and premature ventricular contractions. The arrhythmogenic dose of adrenaline was defined as the lowest dose producing three or more premature ventricular contractions within a 15-s period. We confirmed that centrally administered rilmenidine prevented halothane-adrenaline arrhythmias and then examined the antiarrhythmic effect of rilmenidine in the presence of atropine methylnitrate, a muscarinic receptor antagonist, calphostin C, a PKC inhibitor, HMR-1098, a sarcolemmal K(ATP) inhibitor, 5-hydroxydecanoic acid, a mitochondrial K(ATP) inhibitor or atractyloside, an MPTP opener. KEY RESULTS The antiarrhythmic effect of rilmenidine was significantly inhibited by atropine methylnitrate, calphostin C, 5-hydroxydecanoic acid and atractyloside, but the effects of HMR-1098 in our model were not clear. CONCLUSIONS AND IMPLICATIONS The present results suggest that muscarinic receptors, PKC, mitochondrial K(ATP) channels and MPTP may be crucial components of the mechanism involved in the antiarrhythmic effect of rilmenidine given into the CNS.
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