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Zhang F, Wang QY, Zhou J, Zhou X, Wei X, Hu L, Cheng HL, Yu Q, Cai RL. Electroacupuncture attenuates myocardial ischemia-reperfusion injury by inhibiting microglial engulfment of dendritic spines. iScience 2023; 26:107645. [PMID: 37670780 PMCID: PMC10475514 DOI: 10.1016/j.isci.2023.107645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 06/28/2023] [Accepted: 08/11/2023] [Indexed: 09/07/2023] Open
Abstract
A major side effect of reperfusion therapy following myocardial infarction is myocardial ischemia-reperfusion injury (MIRI). Electroacupuncture preconditioning (EA-pre) has a long history in the treatment of cardiovascular diseases. Here, we demonstrate how EA-pre attenuates MIRI by affecting the phagocytosis of neuronal dendritic spines of microglia of the fastigial nucleus (FNmicroglia). We observed that EA-pre increased activity in FNGABA and then improved myocardial injury by inhibiting abnormal activities of glutaminergic neurons of the FN (FNGlu) during MIRI. Interestingly, we observed changes in the quantity and shape of FN microglia in mice treated with EA-pre and a decrease in the phagocytosis of FNGABA neuronal dendritic spines by microglia. Furthermore, the effects of improving MIRI were reversed when EA-pre mice were chemically activated by intra-FN lipopolysaccharide injection. Overall, our results provide new insight indicating that EA-pre regulates microglial engulfment capacity, thus promoting the improvement of cardiac sympathetic nervous disorder during MIRI.
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Affiliation(s)
- Fan Zhang
- College of Acupuncture and Moxibustion, Anhui University of Chinese Medicine, Hefei, Anhui Province, China
| | - Qian-yi Wang
- College of Acupuncture and Moxibustion, Anhui University of Chinese Medicine, Hefei, Anhui Province, China
| | - Jie Zhou
- College of Acupuncture and Moxibustion, Anhui University of Chinese Medicine, Hefei, Anhui Province, China
| | - Xiang Zhou
- College of Acupuncture and Moxibustion, Anhui University of Chinese Medicine, Hefei, Anhui Province, China
| | - Xia Wei
- College of Acupuncture and Moxibustion, Anhui University of Chinese Medicine, Hefei, Anhui Province, China
| | - Ling Hu
- Institute of Acupuncture and Meridian Research, Anhui Academy of Chinese Medicine, Hefei, Anhui Province, China
| | - Hong-liang Cheng
- The Affiliated Hospital of Acupuncture and Moxibustion, Anhui University of Chinese Medicine, Hefei, Anhui Province, China
| | - Qing Yu
- Institute of Acupuncture and Meridian Research, Anhui Academy of Chinese Medicine, Hefei, Anhui Province, China
| | - Rong-lin Cai
- Institute of Acupuncture and Meridian Research, Anhui Academy of Chinese Medicine, Hefei, Anhui Province, China
- Key Laboratory of Xin’an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei, China
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Kobara M, Amano T, Toba H, Nakata T. Nicorandil Suppresses Ischemia-Induced Norepinephrine Release and Ventricular Arrhythmias in Hypertrophic Hearts. Cardiovasc Drugs Ther 2023; 37:53-62. [PMID: 35895166 DOI: 10.1007/s10557-022-07369-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/19/2022] [Indexed: 01/14/2023]
Abstract
PURPOSE Ventricular arrhythmias (VAs) are a common cause of sudden death in acute myocardial infarction (MI), for which hypertension is a major risk factor. Nicorandil opens ATP-sensitive potassium (KATP) channels, which are expressed by nerve terminals and cardiomyocytes and regulate the release of norepinephrine (NE). However, the effects of nicorandil on ischemic NE release in cardiac tissue remain unclear. Therefore, we herein investigated whether nicorandil suppressed interstitial NE concentrations and VAs during acute MI in pressure overload-induced hypertrophic hearts. METHODS Rats were divided into two groups: an abdominal aortic constriction (AAC) group and sham-operated (Sham) group. Four weeks after constriction, cardiac geometry and functions were examined using echocardiography and hemodynamic analyses. Myocardial ischemia was induced by coronary artery occlusion for 100 min with or without the administration of nicorandil. VAs were assessed by electrocardiography, and NE concentrations in the ischemic region were measured using a micro-dialysis method. RESULTS AAC induced left ventricular hypertrophy with diastolic dysfunction. VAs markedly increased in the early phase (0-20 min) of ischemia in both groups and were more frequent in the AAC group. Cardiac interstitial NE concentrations were higher in the AAC group before ischemia and significantly increased during ischemia in both groups. Nicorandil significantly suppressed ischemia-induced VAs and NE increases in the AAC group. CONCLUSION Ischemia-induced VAs were more frequent in hypertrophic hearts and associated with high interstitial concentrations of NE. The attenuation of ischemia-induced increases in NE through neuronal KATP opening by nicorandil may suppress ischemia-induced VAs in hypertrophic hearts.
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Affiliation(s)
- Miyuki Kobara
- Department of Clinical Pharmacology, Division of Pathological Science, Kyoto Pharmaceutical University, 5 Misasagi Nakauchi-cho, Yamashina-ku, Kyoto, 607-8414, Japan.
| | - Toshihiro Amano
- Department of Clinical Pharmacology, Division of Pathological Science, Kyoto Pharmaceutical University, 5 Misasagi Nakauchi-cho, Yamashina-ku, Kyoto, 607-8414, Japan
| | - Hiroe Toba
- Department of Clinical Pharmacology, Division of Pathological Science, Kyoto Pharmaceutical University, 5 Misasagi Nakauchi-cho, Yamashina-ku, Kyoto, 607-8414, Japan
| | - Tetsuo Nakata
- Department of Clinical Pharmacology, Division of Pathological Science, Kyoto Pharmaceutical University, 5 Misasagi Nakauchi-cho, Yamashina-ku, Kyoto, 607-8414, Japan
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Wang X, Ji X. Interactions between remote ischemic conditioning and post-stroke sleep regulation. Front Med 2021; 15:867-876. [PMID: 34811643 DOI: 10.1007/s11684-021-0887-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 07/31/2021] [Indexed: 12/31/2022]
Abstract
Sleep disturbances are common in patients with stroke, and sleep quality has a critical role in the onset and outcome of stroke. Poor sleep exacerbates neurological injury, impedes nerve regeneration, and elicits serious complications. Thus, exploring a therapy suitable for patients with stroke and sleep disturbances is imperative. As a multi-targeted nonpharmacological intervention, remote ischemic conditioning can reduce the ischemic size of the brain, improve the functional outcome of stroke, and increase sleep duration. Preclinical/clinical evidence showed that this method can inhibit the inflammatory response, mediate the signal transductions of adenosine, activate the efferents of the vagal nerve, and reset the circadian clocks, all of which are involved in sleep regulation. In particular, cytokines tumor necrosis factor α (TNFα) and adenosine are sleep factors, and electrical vagal nerve stimulation can improve insomnia. On the basis of the common mechanisms of remote ischemic conditioning and sleep regulation, a causal relationship was proposed between remote ischemic conditioning and post-stroke sleep quality.
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Affiliation(s)
- Xian Wang
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, 100069, China
| | - Xunming Ji
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, 100069, China. .,Beijing Key Laboratory of Hypoxia Conditioning Translational Medicine, Beijing, 100069, China.
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Hausenloy DJ, Bøtker HE, Ferdinandy P, Heusch G, Ng GA, Redington A, Garcia-Dorado D. Cardiac innervation in acute myocardial ischaemia/reperfusion injury and cardioprotection. Cardiovasc Res 2020; 115:1167-1177. [PMID: 30796814 DOI: 10.1093/cvr/cvz053] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 12/21/2018] [Accepted: 02/21/2019] [Indexed: 12/13/2022] Open
Abstract
Acute myocardial infarction (AMI) and the heart failure (HF) that often complicates this condition, are among the leading causes of death and disability worldwide. To reduce myocardial infarct (MI) size and prevent heart failure, novel therapies are required to protect the heart against the detrimental effects of acute ischaemia/reperfusion injury (IRI). In this regard, targeting cardiac innervation may provide a novel therapeutic strategy for cardioprotection. A number of cardiac neural pathways mediate the beneficial effects of cardioprotective strategies such as ischaemic preconditioning and remote ischaemic conditioning, and nerve stimulation may therefore provide a novel therapeutic strategy for cardioprotection. In this article, we provide an overview of cardiac innervation and its impact on acute myocardial IRI, the role of extrinsic and intrinsic cardiac neural pathways in cardioprotection, and highlight peripheral and central nerve stimulation as a cardioprotective strategy with therapeutic potential for reducing MI size and preventing HF following AMI. This article is part of a Cardiovascular Research Spotlight Issue entitled 'Cardioprotection Beyond the Cardiomyocyte', and emerged as part of the discussions of the European Union (EU)-CARDIOPROTECTION Cooperation in Science and Technology (COST) Action, CA16225.
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Affiliation(s)
- Derek J Hausenloy
- Cardiovascular & Metabolic Disorders Program, Duke-National University of Singapore Medical School, Singapore.,National Heart Research Institute Singapore, National Heart Centre, Singapore.,Yong Loo Lin School of Medicine, National University Singapore, Singapore.,The Hatter Cardiovascular Institute, University College London, London, UK.,The National Institute of Health Research University College London Hospitals Biomedical Research Centre, Research & Development, London, UK.,Tecnologico de Monterrey, Centro de Biotecnologia-FEMSA, Nuevo Leon, Mexico
| | - Hans Erik Bøtker
- Department of Cardiology, Aarhus University Hospital, Aarhus N, Denmark
| | - Peter Ferdinandy
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest, Hungary.,Pharmahungary Group, Szeged, Hungary
| | - Gerd Heusch
- Institute for Pathophysiology, West German Heart and Vascular Center, University of Essen Medical School, Essen, Germany
| | - G André Ng
- Department of Cardiovascular Sciences, University of Leicester, NIHR Leicester Biomedical Research Centre, Glenfield Hospital, UK
| | - Andrew Redington
- Cincinnati Children's Hospital Medical Center, Heart Institute, Cincinnati, OH, USA.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - David Garcia-Dorado
- Department of Cardiology, Vascular Biology and Metabolism Area, Vall d'Hebron University Hospital and Research Institute (VHIR), Universitat Autónoma de Barcelona, Spain.,Instituto CIBER de Enfermedades Cardiovasculares (CIBERCV): Instituto de Salud Carlos III, Madrid, Spain
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Wang Q, Li ZX, Li YJ, He ZG, Chen YL, Feng MH, Li SY, Wu DZ, Xiang HB. Identification of lncRNA and mRNA expression profiles in rat spinal cords at various time‑points following cardiac ischemia/reperfusion. Int J Mol Med 2019; 43:2361-2375. [PMID: 30942426 PMCID: PMC6488167 DOI: 10.3892/ijmm.2019.4151] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Accepted: 03/20/2019] [Indexed: 12/21/2022] Open
Abstract
The identification of the expression patterns of long non-coding RNAs (lncRNAs) and mRNAs in the spinal cord under normal and cardiac ischemia/reperfusion (I/R) conditions is essential for understanding the genetic mechanisms underlying the pathogenesis of cardiac I/R injury. The present study used high-throughput RNA sequencing to investigate differential gene and lncRNA expression patterns in the spinal cords of rats during I/R-induced cardiac injury. Male Sprague Dawley rats were assigned to the following groups: i) Control; ii) 2 h (2 h post-reperfusion); and iii) 0.5 h (0.5 h post-reperfusion). Further mRNA/lncRNA microarray analysis revealed that the expression profiles of lncRNA and mRNA in the spinal cords differed markedly between the control and 2 h groups, and in total 7,980 differentially expressed (>2-fold) lncRNAs (234 upregulated, 7,746 downregulated) and 3,428 mRNAs (767 upregulated, 2,661 downregulated) were identified. Reverse transcription-quantitative polymerase chain reaction analysis was performed to determine the expression patterns of several lncRNAs. The results indicated that the expression levels of lncRNA NONRATT025386 were significantly upregulated in the 2 and 0.5 h groups when compared with those in the control group, whereas the expression levels of NONRATT016113, NONRATT018298 and NONRATT018300 were elevated in the 2 h group compared with those in the control group; however, there was no statistically significant difference between the 0.5 h and control groups. Furthermore, the expression of lncRNA NONRATT002188 was significantly downregulated in the 0.5 and 2 h groups when compared with the control group. The present study determined the expression pattern of lncRNAs and mRNAs in rat spinal cords during cardiac I/R. It was suggested that lncRNAs and mRNAs from spinal cords may be novel therapeutic targets for the treatment of I/R-induced cardiac injury.
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Affiliation(s)
- Qian Wang
- Department of Anesthesiology and Pain Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Zhi-Xiao Li
- Department of Anesthesiology and Pain Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Yu-Juan Li
- Department of Anesthesiology and Pain Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Zhi-Gang He
- Department of Emergency Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Ying-Le Chen
- Department of Anesthesiology, The First Affiliated Quanzhou Hospital of Fujian Medical University, Quanzhou, Fujian 362000, P.R. China
| | - Mao-Hui Feng
- Department of Oncology, Wuhan Peritoneal Cancer Clinical Medical Research Center, Zhongnan Hospital of Wuhan University, Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, Wuhan, Hubei 430071, P.R. China
| | - Shun-Yuan Li
- Department of Anesthesiology, The First Affiliated Quanzhou Hospital of Fujian Medical University, Quanzhou, Fujian 362000, P.R. China
| | - Duo-Zhi Wu
- Department of Anesthesiology, People's Hospital of Hainan Province, Haikou, Hainan 570311, P.R. China
| | - Hong-Bing Xiang
- Department of Anesthesiology and Pain Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
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Fukui Y, Nozawa T, Ihori H, Sobajima M, Nakadate T, Matsuki A, Nonomura M, Fujii N, Inoue H, Kinugawa K. Nicorandil Attenuates Ischemia-Reperfusion Injury Via Inhibition of Norepinephrine Release From Cardiac Sympathetic Nerve Terminals. Int Heart J 2017; 58:787-793. [PMID: 28966311 DOI: 10.1536/ihj.16-391] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A large amount of norepinephrine (NE) released from cardiac sympathetic nerve terminals might accelerate myocardial ischemic injury. Nicorandil (NICO), KATP channel opener, could attenuate cardiac NE release from the sympathetic nerve terminals during ischemia. The present study aimed to investigate the effects of NICO-induced attenuation of cardiac NE release on myocardial ischemia-reperfusion (I/R) injury in rats, by comparison with the effect of cardiac sympathetic denervation on I/R injury.Cardiac interstitial NE (iNE) concentrations were determined using a microdialysis method. Rats were divided into 3 groups; control, NICO, and denervation groups. Cardiac sympathetic denervation was performed by painting 10% phenol on the left ventricular epicardium 7 days before producing ischemia. The left coronary artery was ligated for 30 minutes and then re-perfused for 120 minutes. NICO (50 μg/kg/minute) was infused intravenously starting 20 minutes before the coronary occlusion to the end of the ligation.The infarct size of the left ventricle was smaller in rats treated with NICO than in control rats (20.2 ± 3.0 versus 50.6 ± 14.7%, P < 0.01). Sympathetic denervation also reduced infarct size (28.5 ± 10.4 %, P < 0.01), which was not significantly different from that in the NICO group. At the end of 30-minute ischemia, iNE increased markedly in control rats (0.1 ± 0.1 to 20.6 ± 5.3 × 103 pg/mL), whereas the increase was completely inhibited in denervated rats. NICO markedly attenuated the increase (4.9 ± 3.0 × 103 pg/mL, P < 0.01) during ischemia.NICO-induced attenuation of neural NE release during ischemia might, at least in part, contribute to myocardial protection against I/R injury.
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Affiliation(s)
- Yasutaka Fukui
- Second Department of Internal Medicine, Graduate School of Medicine, University of Toyama
| | - Takashi Nozawa
- Second Department of Internal Medicine, Graduate School of Medicine, University of Toyama
| | - Hiroyuki Ihori
- Second Department of Internal Medicine, Graduate School of Medicine, University of Toyama
| | - Mitsuo Sobajima
- Second Department of Internal Medicine, Graduate School of Medicine, University of Toyama
| | - Teruo Nakadate
- Second Department of Internal Medicine, Graduate School of Medicine, University of Toyama
| | - Akira Matsuki
- Second Department of Internal Medicine, Graduate School of Medicine, University of Toyama
| | - Makoto Nonomura
- Second Department of Internal Medicine, Graduate School of Medicine, University of Toyama
| | - Nozomu Fujii
- Second Department of Internal Medicine, Graduate School of Medicine, University of Toyama
| | - Hiroshi Inoue
- Second Department of Internal Medicine, Graduate School of Medicine, University of Toyama
| | - Koichiro Kinugawa
- Second Department of Internal Medicine, Graduate School of Medicine, University of Toyama
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Horiuchi M. Ischemic preconditioning: Potential impact on exercise performance and underlying mechanisms. ACTA ACUST UNITED AC 2017. [DOI: 10.7600/jpfsm.6.15] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Masahiro Horiuchi
- Division of Human Environmental Science, Mount Fuji Research Institute
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Zhang YQ, Tian F, Zhou Y, Chen YD, Li B, Ma Q, Zhang Y. Nicorandil attenuates carotid intimal hyperplasia after balloon catheter injury in diabetic rats. Cardiovasc Diabetol 2016; 15:62. [PMID: 27059601 PMCID: PMC4826484 DOI: 10.1186/s12933-016-0377-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 03/25/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Diabetic patients suffer from undesired intimal hyperplasia after angioplasty. Nicorandil has a trend to reduce the rate of target lesion revascularization. However, whether nicorandil inhibits intimal hyperplasia and the possible mechanisms underlying it remain to be determined. We aimed at assessing the effect of nicorandil on intimal hyperplasia in diabetic rats. METHODS After intraperitoneal injection of streptozotocin (STZ, 50 mg/kg), balloon injury model was established in carotid arteries of diabetic rats. Rats were randomized to vehicle, nicorandil (15 mg/kg/day) or 5-hydroxydecanoate (5-HD, 10 mg/kg/day), a mitochondrial ATP-sensitive potassium channel (mitoKATP channel)-selective antagonist. Perivascular delivery of εPKC siRNA was conducted to determine the role of εPKC pathway in intimal hyperplasia. In hyperglycemia environment (25 mM glucose), primary culture of vascular smooth muscle cells (VSMCs) were treated with nicorandil or 5-HD. Cell proliferation and cell migration were analyzed. RESULTS Intimal hyperplasia significantly increased 14 days after balloon injury in diabetic rats (p < 0.01). Nicorandil inhibited intima development, reduced inflammation and prevented cell proliferation in balloon-injured arteries (p < 0.01). The protective effects of nicorandil were reversed by 5-HD (p < 0.05). εPKC was activated in balloon-injured arteries (p < 0.01). Nicorandil inhibited εPKC activation by opening mitoKATP channel. Perivascular delivery of εPKC siRNA inhibited intimal hyperplasia, inflammation and cell proliferation (p < 0.01). High glucose-induced VSMCs proliferation and migration were inhibited by nicorandil. εPKC activation induced by high glucose was also inhibited by nicorandil and that is partially reversed by 5-HD. εPKC knockdown prevented VSMCs proliferation and migration (p < 0.01). CONCLUSIONS Our study demonstrates that nicorandil inhibits intimal hyperplasia in balloon-injured arteries in diabetic rats. Nicorandil also prevents VSMCs proliferation and migration induced by high glucose. The beneficial effect of nicorandil is conducted via opening mitoKATP channel and inhibiting εPKC activation.
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Affiliation(s)
- Ying Qian Zhang
- Department of Cardiology, Chinese PLA General Hospital, 28 Fuxing Rd, Beijing, 100853, China
| | - Feng Tian
- Department of Cardiology, Chinese PLA General Hospital, 28 Fuxing Rd, Beijing, 100853, China
| | - Ying Zhou
- Department of Cardiology, Chinese PLA General Hospital, 28 Fuxing Rd, Beijing, 100853, China
| | - Yun Dai Chen
- Department of Cardiology, Chinese PLA General Hospital, 28 Fuxing Rd, Beijing, 100853, China.
| | - Bo Li
- Department of Cardiology, Chinese PLA General Hospital, 28 Fuxing Rd, Beijing, 100853, China
| | - Qiang Ma
- Department of Cardiology, Chinese PLA General Hospital, 28 Fuxing Rd, Beijing, 100853, China
| | - Ying Zhang
- Department of Cardiology, Chinese PLA General Hospital, 28 Fuxing Rd, Beijing, 100853, China
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Horiuchi M, Endo J, Thijssen DHJ. Impact of ischemic preconditioning on functional sympatholysis during handgrip exercise in humans. Physiol Rep 2015; 3:3/2/e12304. [PMID: 25713329 PMCID: PMC4393211 DOI: 10.14814/phy2.12304] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Repeated bouts of ischemia followed by reperfusion, known as ischemic preconditioning (IPC), is found to improve exercise performance. As redistribution of blood from the inactive areas to active skeletal muscles during exercise (i.e., functional sympatholysis) is important for exercise performance, we examined the hypothesis that IPC improves functional sympatholysis in healthy, young humans. In a randomized study, 15 healthy young men performed a 10-min resting period, dynamic handgrip exercise at 10% maximal voluntary contraction (MVC), and 25% MVC. This protocol was preceded by IPC (IPC; 4 × 5-min 220-mmHg unilateral occlusion) or a sham intervention (CON; 4 × 5-min 20-mmHg unilateral occlusion). Near-infrared spectroscopy was used to assess changes in oxygenated hemoglobin and myoglobin in skeletal muscle (HbO2 + MbO2) in response to sympathetic activation (via cold pressor test (CPT)) at baseline and during handgrip exercise (at 10% and 25%). In resting conditions, HbO2 + MbO2 significantly decreased during CPT (−11.0 ± 1.0%), which was significantly larger during the IPC-trial (−13.8 ± 1.2%, P = 0.006). During handgrip exercise at 10% MVC, changes in HbO2 + MbO2 in response to the CPT were blunted after IPC (−8.8 ± 1.5%) and CON (−8.3 ± 0.4%, P = 0.593). During handgrip exercise at 25% MVC, HbO2 + MbO2 in response to the CPT increased (2.0 ± 0.4%), whereas this response was significantly larger when preceded by IPC (4.2 ± 0.6%, P = 0.027). Collectively, these results indicate that IPC-induced different vascular changes at rest and during moderate exercise in response to sympathetic activation. This suggests that, in healthy volunteers, exposure to IPC may alter tissue oxygenation during sympathetic stimulation at rest and during exercise.
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Affiliation(s)
- Masahiro Horiuchi
- Division of Human Environmental Science, Mt. Fuji Research Institute, Fuji-yoshida cityYamanashi, Japan
| | - Junko Endo
- Division of Human Environmental Science, Mt. Fuji Research Institute, Fuji-yoshida cityYamanashi, Japan
| | - Dick H J Thijssen
- Research Institute of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK Radboud University Medical Center, Radboud Institute for Health Sciences, Nijmegen, Netherlands
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Dynamics of interstitial calcium in rat myocardial ischemia reperfusion injury in vivo. JOURNAL OF HUAZHONG UNIVERSITY OF SCIENCE AND TECHNOLOGY. MEDICAL SCIENCES = HUA ZHONG KE JI DA XUE XUE BAO. YI XUE YING DE WEN BAN = HUAZHONG KEJI DAXUE XUEBAO. YIXUE YINGDEWEN BAN 2014; 34:37-41. [PMID: 24496677 DOI: 10.1007/s11596-014-1229-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Revised: 11/30/2013] [Indexed: 10/25/2022]
Abstract
Intracellular calcium overload is a key factor for myocardial ischemia reperfusion injury (IR). However, there was no report for interstitial calcium concentration dynamics. We investigated the interstitial calcium dynamics in rat myocardial IR model in vivo. A microdialysis system was involved, and the time delay of the system and recovery time was introduced and tested with a fluids switching method. Twelve SD rats were divided into IR or control group. Myocardial IR was induced by ligating (20 min) then releasing (60 min) the suture underlying left anterior descending branch. Mycrodialyisis probe was implanted into the left ventricular myocardium perfusion area for occlusion. Dialysate samples were collected every 10 min. Dialysate calcium concentration was detected with an atomic absorption spectrophotometer. Recovery time for the microdialysis system was 20 min, and recovery rate was 16%. Dialysate calcium concentration showed no changes during ischemia, descended immediately after reperfusion, reached the lowest level (67% of baseline value) 20 min after reperfusion, then escalated slowly. Recovery time was an important parameter for mycrodialysis technique, and it should not be neglected and needed to be tested. Our data suggest that interstitial calcium concentration in rats with myocardial IR in vivo kept steady in ischemia, descended rapidly at the initial reperfusion, then rebounded slowly. In conclusion, we introduced the concept of recovery time for microdialysis and provided a simple testing method.
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Desipramine pretreatment improves sympathetic remodeling and ventricular fibrillation threshold after myocardial ischemia. J Biomed Biotechnol 2012; 2012:732909. [PMID: 23093858 PMCID: PMC3471026 DOI: 10.1155/2012/732909] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Revised: 05/06/2012] [Accepted: 05/06/2012] [Indexed: 11/17/2022] Open
Abstract
Abnormal increase in sympathetic nerve sprouting was responsible for the ventricular arrhythmogenesis after myocardial infarction. This study investigated whether the norepinephrine transporter inhibitor, desipramine, can modulate sympathetic remodeling and ventricular fibrillation threshold (VFT) after myocardial ischemia-reperfusion. Rats were administered desipramine (0.8 mg/kg, i.v.) before or after myocardial ischemia. VFT, infarct size, tyrosine hydroxylase (TH) and growth-associated protein 43 (GAP43)-positive nerve fibers were measured after one week. The VFT of preischemic treatment group was 11.0 ± 2.65 V and significantly higher than that of control ischemic group (7.2 ± 1.30 V, P < 0.05). Infarct size in the preischemic treatment group (23.3 ± 2.4%) was significantly lower than that in the control ischemic group (30.8 ± 1.3%, P < 0.05) and the delayed application group (27.1 ± 2.6%, P < 0.05). The density of TH and GAP43-positive nerve fibers in the control ischemic group was significantly higher than that in the other three groups (P < 0.05). The density of nerve fibers improved after desipramine treatment. Moreover, there was a negative correlation between the VFT and both TH and GAP43-positive nerve fiber density in the infarct border zone (P < 0.05). Desipramine treatment before acute myocardial ischemia can decrease infarct size, improve sympathetic remodeling, and increase VFT and electrical stability of ischemic hearts. Desipramine appears to cause myocardial ischemic preconditioning.
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Direct Protective Effects of Dexmedetomidine Against Myocardial Ischemia-Reperfusion Injury in Anesthetized Pigs. Shock 2012; 38:92-7. [DOI: 10.1097/shk.0b013e318254d3fb] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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13
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Zhou W, Ko Y, Benharash P, Yamakawa K, Patel S, Ajijola OA, Mahajan A. Cardioprotection of electroacupuncture against myocardial ischemia-reperfusion injury by modulation of cardiac norepinephrine release. Am J Physiol Heart Circ Physiol 2012; 302:H1818-25. [PMID: 22367505 DOI: 10.1152/ajpheart.00030.2012] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Augmentation of cardiac sympathetic tone during myocardial ischemia has been shown to increase myocardial O(2) demand and infarct size as well as induce arrhythmias. We have previously demonstrated that electroacupuncture (EA) inhibits the visceral sympathoexcitatory cardiovascular reflex. The purpose of this study was to determine the effects of EA on left ventricular (LV) function, O(2) demand, infarct size, arrhythmogenesis, and in vivo cardiac norepinephrine (NE) release in a myocardial ischemia-reperfusion model. Anesthetized rabbits (n = 36) underwent 30 min of left anterior descending coronary artery occlusion followed by 90 min of reperfusion. We evaluated myocardial O(2) demand, infarct size, ventricular arrhythmias, and myocardial NE release using microdialysis under the following experimental conditions: 1) untreated, 2) EA at P5-6 acupoints, 3) sham acupuncture, 4) EA with pretreatment with naloxone (a nonselective opioid receptor antagonist), 5) EA with pretreatment with chelerythrine (a nonselective PKC inhibitor), and 6) EA with pretreatment with both naloxone and chelerythrine. Compared with the untreated and sham acupuncture groups, EA resulted in decreased O(2) demand, myocardial NE concentration, and infarct size. Furthermore, the degree of ST segment elevation and severity of LV dysfunction and ventricular arrhythmias were all significantly decreased (P < 0.05). The cardioprotective effects of EA were partially blocked by pretreatment with naloxone or chelerythrine alone and completely blocked by pretreatment with both naloxone and chelerythrine. These results suggest that the cardioprotective effects of EA against myocardial ischemia-reperfusion are mediated through inhibition of the cardiac sympathetic nervous system as well as opioid and PKC-dependent pathways.
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Affiliation(s)
- Wei Zhou
- Department of Anesthesiology, David Geffen School Medicine, University of California, Los Angeles, California 90095, USA.
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Sakata Y, Nakatani D, Shimizu M, Suna S, Usami M, Matsumoto S, Hara M, Sumitsuji S, Kawano S, Iwakura K, Hamasaki T, Sato H, Nanto S, Hori M, Komuro I. Oral treatment with nicorandil at discharge is associated with reduced mortality after acute myocardial infarction. J Cardiol 2012; 59:14-21. [DOI: 10.1016/j.jjcc.2011.08.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2011] [Revised: 08/01/2011] [Accepted: 08/04/2011] [Indexed: 10/17/2022]
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15
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Naumenko SE, Latysheva TV, Gilinsky MA. Ischemic postconditioning and size of myocardial infarction during inhibition of norepinephrine reuptake. Bull Exp Biol Med 2011; 152:192-4. [DOI: 10.1007/s10517-011-1485-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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16
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Naumenko SE, Latysheva TV, Gilinskii MA. Inhibition of Norepinephrine Reuptake and Size of Myocardial Infarction during Focal Ischemia and after Preconditioning. Bull Exp Biol Med 2010; 150:15-7. [DOI: 10.1007/s10517-010-1056-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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17
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Miura H, Toyama K, Pratt PF, Gutterman DD. Cigarette smoking impairs Na+-K+-ATPase activity in the human coronary microcirculation. Am J Physiol Heart Circ Physiol 2010; 300:H109-17. [PMID: 21076023 DOI: 10.1152/ajpheart.00237.2010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The extracellular K(+) concentration ([K(+)](o)) has been proposed to link cardiac metabolism with coronary perfusion and arrhythmogenesis, particularly during ischemia. Several animal studies have also supported K(+) as an EDHF that activates Na(+)-K(+)-ATPase and/or inwardly rectifying K(+) (K(ir)) channels. Therefore, we examined the vascular reactivity of human coronary arterioles (HCAs) to small elevations in [K(+)](o), the influence of risk factors for coronary disease, and the role of K(+) as an EDHF. Changes in the internal diameter of HCAs were recorded with videomicroscopy. Most vessels dilated to increases in [K(+)](o) with a maximal dilation of 55 ± 6% primarily at 12.5-20.0 mM KCl (n = 38, average: 16 ± 1 mM). Ouabain, a Na(+)-K(+)-ATPase inhibitor, alone reduced the dilation, and the addition of Ba(2+), a K(ir) channel blocker, abolished the remaining dilation, whereas neither endothelial denudation nor Ba(2+) alone reduced the dilation. Multivariate analysis revealed that cigarette smoking was the only risk factor associated with impaired dilation to K(+). Ouabain significantly reduced the vasodilation in HCAs from subjects without cigarette smoking but not in those with smoking. Cigarette smoking downregulated the expression of the Na(+)-K(+)-ATPase catalytic α(1)-subunit but not Kir2.1 in the vessels. Ouabain abolished the dilation in endothelium-denuded vessels to a same extent to that with the combination of ouabain and Ba(2+) in endothelium-intact vessels, whereas neither ouabain nor ouabain plus Ba(2+) reduced EDHF-mediated dilations to bradykinin and ADP. A rise in [K(+)](o) dilates HCAs primarily via the activation of Na(+)-K(+)-ATPase in vascular smooth muscle cells with a considerable contribution of K(ir) channels in the endothelium, indicating that [K(+)](o) may modify coronary microvascular resistance in humans. Na(+)-K(+)-ATPase activity is impaired in subjects who smoke, possibly contributing to dysregulation of the coronary microcirculation, excess ischemia, and arrhythmogenesis in those subjects. K(+) does not likely serve as an EDHF in the human coronary arteriolar dilation to bradykinin and ADP.
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Affiliation(s)
- Hiroto Miura
- Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
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18
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Acute effects of intravenous nicorandil on hemodynamics in patients hospitalized with acute decompensated heart failure. J Cardiol 2010; 56:291-9. [DOI: 10.1016/j.jjcc.2010.06.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2010] [Revised: 06/15/2010] [Accepted: 06/24/2010] [Indexed: 10/19/2022]
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19
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Wang JS, Wu MH, Mao TY, Fu TC, Hsu CC. Effects of normoxic and hypoxic exercise regimens on cardiac, muscular, and cerebral hemodynamics suppressed by severe hypoxia in humans. J Appl Physiol (1985) 2010; 109:219-29. [PMID: 20431021 DOI: 10.1152/japplphysiol.00138.2010] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Hypoxic preconditioning prevents cerebrovascular/cardiovascular disorders by increasing resistance to acute ischemic stress, but severe hypoxic exposure disturbs vascular hemodynamics. This study compared how various exercise regimens with/without hypoxia affect hemodynamics and oxygenation in cardiac, muscle, and cerebral tissues during severe hypoxic exposure. Sixty sedentary males were randomly divided into five groups. Each group (n = 12) received one of five interventions: 1) normoxic (21% O(2)) resting control, 2) hypoxic (15% O(2)) resting control, 3) normoxic exercise (50% maximum work rate under 21% O(2); N-E group), 4) hypoxic-relative exercise (50% maximal heart rate reserve under 15% O(2); H-RE group), or 5) hypoxic-absolute exercise (50% maximum work rate under 15% O(2); H-AE group) for 30 min/day, 5 days/wk, for 4 wk. A recently developed noninvasive bioreactance device was used to measure cardiac hemodynamics, and near-infrared spectroscopy was used to assess perfusion and oxygenation in the vastus lateralis (VL)/gastrocnemius (GN) muscles and frontal cerebral lobe (FC). Our results demonstrated that the H-AE group had a larger improvement in aerobic capacity compared with the N-E group. Both H-RE and H-AE ameliorated the suppression of cardiac stroke volume and the GN hyperemic response (Delta total Hb/min) and reoxygenation rate by acute 12% O(2) exposure. Simultaneously, the two hypoxic interventions enhanced perfusion (Delta total Hb) and O(2) extraction [Delta deoxyHb] of the VL muscle during the 12% O(2) exercise. Although acute 12% O(2) exercise decreased oxygenation (Delta O(2)Hb) of the FC, none of the 4-wk interventions influenced the cerebral perfusion and oxygenation during normoxic/hypoxic exercise tests. Therefore, we conclude that moderate hypoxic exercise training improves cardiopulmonary fitness and increases resistance to disturbance of cardiac hemodynamics by severe hypoxia, concurrence with enhancing O(2) delivery/utilization in skeletal muscles but not cerebral tissues.
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Affiliation(s)
- Jong-Shyan Wang
- Graduate Institute of Rehabilitation Science, Chang Gung University, 259 Wen-Hwa 1st Rd., Kwei-Shan, Tao-Yuan 333, Taiwan.
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Miura T, Miki T, Yano T. Role of the gap junction in ischemic preconditioning in the heart. Am J Physiol Heart Circ Physiol 2010; 298:H1115-25. [DOI: 10.1152/ajpheart.00879.2009] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The gap junction plays roles not only in electrical coupling of cardiomyocytes but also in intercellular transport of biologically active substances. Furthermore, the gap junction participates in decision making on cell survival versus cell death in various types of cells, and a part of reperfusion injury in the heart has been indicated to be gap junction mediated. The contribution of gap junction communication (GJC) and/or mitochondrial “hemichannels” to protective signaling during the trigger phase of ischemic preconditioning (IPC) is suggested by observations that IPC failed to protect the heart when GJC was blocked during IPC. Although ischemia suppresses both electrical and chemical GJC, chemical GJC persists for a considerable time after electrical GJC is lost. IPC facilitates the ischemia-induced suppression of chemical GJC, whereas IPC delays the reduction of electrical GJC after ischemia. The inhibition of GJC during sustained ischemia and reperfusion by GJC blockers mimics the effect of IPC on myocardial necrosis. IPC induces distinct effects on the interaction of connexin-43 with protein kinases, and the phosphorylation of connexin-43 at Ser368 by PKCε is a primary mechanism of inhibition of chemical GJC by IPC. Several lines of evidence support the notion that the modulation of GJC is a part of the mechanism of IPC-induced protection against myocardial necrosis and arrhythmias, though what percentage of IPC protection is attributable to the inhibition of GJC during ischemia-reperfusion still remains unclear.
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Affiliation(s)
- Tetsuji Miura
- Division of Cardiology, Second Department of Internal Medicine, Sapporo Medical University, School of Medicine, Sapporo, Japan
| | - Takayuki Miki
- Division of Cardiology, Second Department of Internal Medicine, Sapporo Medical University, School of Medicine, Sapporo, Japan
| | - Toshiyuki Yano
- Division of Cardiology, Second Department of Internal Medicine, Sapporo Medical University, School of Medicine, Sapporo, Japan
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Postconditioning Improves Postischemic Cardiac Dysfunction Independently of Norepinephrine Overflow After Reperfusion in Rat Hearts: Comparison With Preconditioning. J Cardiovasc Pharmacol 2010; 55:6-13. [DOI: 10.1097/fjc.0b013e3181bfb1c1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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22
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Despas F, Trouillet C, Franchitto N, Labrunee M, Galinier M, Senard JM, Pathak A. Levosimedan improves hemodynamics functions without sympathetic activation in severe heart failure patients: Direct evidence from sympathetic neural recording. ACTA ACUST UNITED AC 2009; 12:25-30. [DOI: 10.3109/17482940903434077] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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23
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Lee TM, Lin MS, Chang NC. Effect of pravastatin on sympathetic reinnervation in postinfarcted rats. Am J Physiol Heart Circ Physiol 2007; 293:H3617-26. [PMID: 17890424 DOI: 10.1152/ajpheart.00875.2007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We assessed whether pravastatin attenuates cardiac sympathetic reinnervation after myocardial infarction through the activation of ATP-sensitive K+(KATP) channels. Epidemiological studies have shown that men treated with statins appear to have a lower incidence of sudden death than men without statins. However, the specific factor for this has remained disappointingly elusive. Twenty-four hours after ligation of the anterior descending artery, male Wistar rats were randomized to groups treated with either vehicle, nicorandil (a specific mitochondrial KATPchannel agonist), pinacidil (a nonspecific KATPchannel agonist), pravastatin, glibenclamide (a KATPchannel blocker), or a combination of nicorandil and glibenclamide, pinacidil and glibenclamide, or pravastatin and glibenclamide for 4 wk. Myocardial norepinephrine levels revealed a significant elevation in vehicle-treated rats at the remote zone compared with sham-operated rats (2.54 ± 0.17 vs. 1.26 ± 0.36 μg/g protein, P < 0.0001), consistent with excessive sympathetic reinnervation after infarction. Immunohistochemical analysis for tyrosine hydroxylase, growth-associated factor 43, and neurofilament also confirmed the change of myocardial norepinephrine. This was paralleled by a significant upregulation of tyrosine hydroxylase protein expression and mRNA in vehicle-treated rats, which was reduced after the administration of either nicorandil, pinacidil, or pravastatin. Arrhythmic scores during programmed stimulation in vehicle-treated rats were significantly higher than those treated with pravastatin. In contrast, the beneficial effects of pravastatin were reversed by the addition of glibenclamide, implicating KATPchannels as the relevant target. The sympathetic reinnervation after infarction is modulated by the activation of KATPchannels. Chronic use of pravastatin after infarction, resulting in attenuated sympathetic reinnervation by the activation of KATPchannels, may modify the arrhythomogenic response to programmed electrical stimulation.
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Affiliation(s)
- Tsung-Ming Lee
- Cardiology Section, Department of Medicine, Taipei Medical University, 252 Wu-Hsing Street, Taipei, Taiwan
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Tei A, Tabuchi M, Nejime N, Kubota Y, Kagota S, Higashino H, Hashimoto M, Shinozuka K. NICORANDIL MAY CHANGE THE SYMPATHETIC NERVE ACTIVITY OF SHR.Cg-Lepr cp/NDmcr RATS. Clin Exp Pharmacol Physiol 2007. [DOI: 10.1111/j.1440-1681.2007.04768.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Kashimoto S, Seki M, Ishiguro T, Yoshioka H, Nagata O, Nishimura K, Kikuchi T, Yamada T, Iwade M, Omi A, Honda O, Sakamoto A, Ogihara Y, Fujimoto K, Nakaigawa Y, Kato J, Watanabe A, Nomura M, Takeda J. Nicorandil decreases cardiac events during and after noncardiac surgery. J Clin Anesth 2007; 19:44-8. [PMID: 17321926 DOI: 10.1016/j.jclinane.2006.05.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2005] [Revised: 05/17/2006] [Accepted: 05/17/2006] [Indexed: 11/15/2022]
Abstract
STUDY OBJECTIVE To assess whether nicorandil reduces the likelihood of cardiac events during and after intermediate risk surgery. DESIGN Multicenter study. SETTING 13 hospitals in Japan. PATIENTS Intermediate-risk patients were identified by the presence of risk factors such as angina, a history of myocardial infarction, heart failure, diabetes mellitus, and abnormal electrocardiography (ECG). INTERVENTIONS Nicorandil was given to these patients during the operation. MEASUREMENTS AND MAIN RESULTS Cardiac events during the operation and the following 5 days were monitored. The frequency of cardiac events in nicorandil-treated patients was compared with those in nontreated patients. Eighty-four patients received nicorandil during surgery and 237 patients received standard care. Cardiac events in the nicorandil-treated group occurred less frequently both during the operation (odds ratio, 0.15; 95% confidence interval, 0.03-0.76; P=0.02) and after it (odds ratio, 0.24; 95% confidence interval, 0.06-0.90; P=0.04). CONCLUSIONS Nicorandil reduces the frequency of cardiac events in patients undergoing noncardiac surgery, both during and after the operation.
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Affiliation(s)
- Satoshi Kashimoto
- Department of Anesthesiology, Faculty of Medicine, University of Yamanashi, Tamaho, Yamanashi 409-3898, and Department of Anesthesia, Cancer Institute Hospital, Tokyo, Japan.
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Kasama S, Toyama T, Hatori T, Sumino H, Kumakura H, Takayama Y, Ichikawa S, Suzuki T, Kurabayashi M. Effects of Intravenous Atrial Natriuretic Peptide on Cardiac Sympathetic Nerve Activity and Left Ventricular Remodeling in Patients With First Anterior Acute Myocardial Infarction. J Am Coll Cardiol 2007; 49:667-74. [PMID: 17291931 DOI: 10.1016/j.jacc.2006.09.048] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2006] [Revised: 08/22/2006] [Accepted: 09/18/2006] [Indexed: 11/16/2022]
Abstract
OBJECTIVES We sought to evaluate the effects of atrial natriuretic peptide (ANP) on cardiac sympathetic nerve activity (CSNA) and left ventricular (LV) remodeling in patients with first anterior acute myocardial infarction (AMI) after primary coronary angioplasty. BACKGROUND The activation of the renin-angiotensin-aldosterone system (RAAS) prevents the uptake of norepinephrine in the myocardium. Atrial natriuretic peptide, a circulating hormone of cardiac origin, has vasodilatory and diuretic properties, and can inhibit the RAAS. METHODS We studied 50 patients with first anterior AMI who were randomly assigned to receive ANP (group A) or isosorbide dinitrate (group B) before and after primary coronary angioplasty. The ANP or ISDN was continuously infused >48 h. The extent score (ES) was determined from 99mTc-pyrophosphate scintigraphy to evaluate the area of initial myocardial damage 3 to 5 days after primary angioplasty. The LV end-diastolic volume (LVEDV) and LV ejection fraction (LVEF) were determined by left ventriculography 2 weeks later. The delayed heart/mediastinum count (H/M) ratio, delayed total defect score (TDS), and washout rate (WR) were determined from 123I-meta-iodobenzylguanidine scintigraphy after 3 weeks. RESULTS After primary angioplasty, age, gender, risk factors, peak serum creatine phosphokinase concentration, recanalization time, and ES were similar in the 2 groups. However, in group A (n = 25), the TDS was significantly lower (34 +/- 8 vs. 41 +/- 8; p < 0.05), the H/M ratio was significantly higher (1.96 +/- 0.18 vs. 1.74 +/- 0.23; p < 0.05), and the WR was significantly lower (35 +/- 8% vs. 44 +/- 12%; p < 0.005) than in group B (n = 25). Moreover, the LVEDV and LVEF in group A were better than in group B (LVEDV: 85.5 +/- 28.5 ml vs. 106.3 +/- 39.4 ml [p < 0.05]; LVEF: 47.9 +/- 10.2% vs. 41.5 +/- 11.8% [p < 0.05]). CONCLUSIONS Intravenous ANP improves CSNA and prevents LV remodeling in patients with first anterior AMI.
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Affiliation(s)
- Shu Kasama
- Department of Cardiovascular Medicine, Gunma University School of Medicine, Maebashi, Japan.
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Nakadate T, Nozawa T, Matsuki A, Nonomura M, Igarashi N, Igawa A, Inoue H. Brief Episode of Myocardial Ischemia Before Prolonged Ischemia Attenuates Cardiac Sympathetic Nerve Injury. Circ J 2006; 70:919-25. [PMID: 16799249 DOI: 10.1253/circj.70.919] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND The aim of this study was to investigate the effects of brief ischemia before prolonged ischemia on cardiac sympathetic neural function. Brief ischemia inhibits the sympathetic neural release of norepinephrine (NE) during subsequent sustained ischemia. However, whether it can attenuate the neural function after sustained ischemia remains unknown. METHODS AND RESULTS Sympathetic neural function was assessed using 123I-metaiodobenzylguanidine (MIBG) in patients who with (Group I) or without angina (Group II) within 3 days prior to acute myocardial infarction. In the rat experiment, cardiac interstitial NE (iNE) with or without pretreatment of 5-min coronary ligation was determined during a 30-min occlusion. Differences between MIBG and Thallium-201 for the total defect score were significantly greater in Group II than in Group I (6.1 +/- 4.0 vs 0.4 +/- 4.4). Levels of iNE were less in rats with a 5-min pretreatment (7.3 +/- 2.3 vs 18.6 +/- 5.9 x 10(3) pg/ml, p < 0.01) and MIBG uptake of ischemic region was greater (0.061 +/- 0.029 vs 0.031 +/- 0.011 %kg dose/g, p < 0.05) compared with rats without the pretreatment. CONCLUSION A brief episode of ischemia attenuates the sympathetic neural injury caused by subsequent prolonged ischemia and this protective effect is associated with attenuation of NE release during the prolonged ischemia.
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Affiliation(s)
- Teruo Nakadate
- The Second Department of Internal Medicine, University of Toyama, School of Medicine, Toyama, Japan
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Kasama S, Toyama T, Hatori T, Kumakura H, Takayama Y, Ichikawa S, Suzuki T, Kurabayashi M. Comparative effects of nicorandil with isosorbide mononitrate on cardiac sympathetic nerve activity and left ventricular function in patients with ischemic cardiomyopathy. Am Heart J 2005; 150:477. [PMID: 16169327 DOI: 10.1016/j.ahj.2005.06.030] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2005] [Accepted: 06/17/2005] [Indexed: 11/30/2022]
Abstract
BACKGROUND Nicorandil, an adenosine triphosphate-sensitive potassium channel opener, improves left ventricular (LV) remodeling after myocardial infarction in rat models. However, the effects of chronic nicorandil therapy on cardiac sympathetic nerve activity in patients with ischemic cardiomyopathy have not been determined. METHODS Thirty-six patients with ischemic cardiomyopathy (LV ejection fraction [LVEF] < 40%) who underwent successful revascularization procedure before 6 months were treated by standard conventional therapy. Eighteen patients were randomized to additionally receive nicorandil (15 mg/d), whereas the other 18 patients received isosorbide mononitrate (40 mg/d). The delayed heart-to-mediastinum count ratio (H/M ratio), delayed total defect score (TDS), and washout rate (WR) were determined from (123)I-meta-iodobenzylguanidine (MIBG) scintigraphy before and 6 months after treatment. Left ventricular end-diastolic volume (LVEDV) and LVEF were determined by echocardiography. RESULTS Total defect score, H/M ratio, WR, LVEDV, and LVEF at baseline were similar for both groups. After treatment, in patients receiving nicorandil, TDS decreased from 50 +/- 6 to 40 +/- 11 (P < .005), H/M ratio increased from 1.68 +/- 0.23 to 1.79 +/- 0.26 (P = .005), and WR decreased from 46% +/- 9% to 40% +/- 12% (P < .005). In addition, LVEDV decreased from 178 +/- 31 to 157 +/- 30 mL (P < .0005), and LVEF increased from 33% +/- 6% to 39% +/- 7% (P < .05). In patients receiving isosorbide mononitrate, no significant changes were observed in these parameters. Moreover, there was a significant correlation between the percent change of LVEF and that of TDS from baseline to 6 months in the patients receiving nicorandil (r = -0.569, P < .05). CONCLUSIONS The present study demonstrates improvements in cardiac (123)I-MIBG scintigraphic and echocardiographic parameters with nicorandil treatment. These findings indicate that nicorandil can improve cardiac sympathetic nerve activity and LV function in patients with ischemic cardiomyopathy.
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Affiliation(s)
- Shu Kasama
- Department of Cardiovascular Medicine, Gunma University School of Medicine, Maebashi, Japan.
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Moraru L, Tong S, Malhotra A, Geocadin R, Thakor N, Bezerianos A. Investigation of the effects of ischemic preconditioning on the HRV response to transient global ischemia using linear and nonlinear methods. Med Eng Phys 2005; 27:465-73. [PMID: 15990063 DOI: 10.1016/j.medengphy.2004.12.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2003] [Revised: 12/10/2004] [Accepted: 12/17/2004] [Indexed: 11/17/2022]
Abstract
Ischemic preconditioning (IP) has been used as a strategy to prevent cell death in various organs, including the brain and the heart. Investigation of the effects of ischemic preconditioning mostly employed models with reduced complexity, such as cell cultures, tissue slices or perfused organ preparations. Although such models can provide valuable insight into the protective mechanism of preconditioning, the functional (re)organization of the control mechanisms at the level of the living organism cannot be assessed. The purpose of the present animal model study was to evaluate the effect of global ischemic preconditioning on the heart rate variability (HRV) response to the asphyxia insult. The data consisted of 4 h RR interval measurements recorded in five preconditioned and five non-preconditioned Wistar rats. Using linear (time and frequency domain) and nonlinear (approximate entropy and parameters of Poincare plots) measures, we evaluated the dynamic time course of the HRV response to the asphyxia insult and the effect of preconditioning on the autonomic neurocardiac control. Both the linear and nonlinear parameters indicate a faster recovery of the baseline HRV corresponding to the preconditioned groups, though only the spectral analysis identifies a statistically significant difference between the two groups. For the preconditioned group, at about 90 min after the asphyxic insult, the autonomic neural balance (measured by LF/HF ratio) appears fully recovered. The small variation of the rest of the parameters indicates the necessity of further investigation including the design of a larger study with a higher statistical power. Our results show for the first time that global ischemic preconditioning influences the HRV response to the asphyxia injury. The neuroprotective effect of preconditioning translates into a faster recovery of the basal HRV and the autonomic modulation of the heart.
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Affiliation(s)
- L Moraru
- Department of Medical Physics, School of Medicine, University of Patras, Patras, Greece
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Kasama S, Toyama T, Kumakura H, Takayama Y, Ichikawa S, Suzuki T, Kurabayashi M. Effects of nicorandil on cardiac sympathetic nerve activity after reperfusion therapy in patients with first anterior acute myocardial infarction. Eur J Nucl Med Mol Imaging 2004; 32:322-8. [PMID: 15791442 DOI: 10.1007/s00259-004-1672-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2004] [Accepted: 08/12/2004] [Indexed: 10/25/2022]
Abstract
PURPOSE Ischaemic preconditioning (PC) is a cardioprotective phenomenon in which short periods of myocardial ischaemia result in resistance to decreased contractile dysfunction during a subsequent period of sustained ischaemia. Nicorandil, an ATP-sensitive potassium channel opener, can induce PC effects on sympathetic nerves during myocardial ischaemia. However, its effects on cardiac sympathetic nerve activity (CSNA) and left ventricular remodelling have not been determined. In this study, we sought to determine whether nicorandil administration improves CSNA in patients with acute myocardial infarction (AMI). METHODS We studied 58 patients with first anterior AMI, who were randomly assigned to receive nicorandil (group A) or isosorbide dinitrate (group B) after primary coronary angioplasty. The nicorandil or isosorbide dinitrate was continuously infused for >48 h. The extent score (ES) was determined from 99mTc-pyrophosphate scintigraphy, and the total defect score (TDS) was determined from 201Tl scintigraphy 3-5 days after primary angioplasty. The left ventricular end-diastolic volume (LVEDV) and left ventricular ejection fraction (LVEF) were determined by left ventriculography 2 weeks later. The delayed heart/mediastinum count (H/M) ratio, delayed TDS and washout rate (WR) were determined from 123I-meta-iodobenzylguanidine (MIBG) images 3 weeks later. The left ventriculography results were re-examined 6 months after treatment. RESULTS Fifty patients originally enrolled in the trial completed the entire protocol. After treatment, no significant differences were observed in ES or left ventricular parameters between the two groups. However, in group A (n=25), the TDSs determined from 201Tl and 123I-MIBG were significantly lower (26+/-6 vs 30+/-5, P<0.01, and 32+/-8 vs 40+/-6, P<0.0001, respectively), the H/M ratio significantly higher (1.99+/-0.16 vs 1.77+/-0.30, P<0.005) and the WR significantly lower (36%+/-8% vs 44%+/-12%, P<0.005) than in group B (n=25). Moreover, 6 months after treatment, LVEDV and LVEF were better in group A than in group B. CONCLUSION These findings indicate that nicorandil can have beneficial effects on CSNA and left ventricular remodelling in patients with first anterior AMI.
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Affiliation(s)
- Shu Kasama
- Department of Cardiovascular Medicine, Gunma University School of Medicine, 3-39-15, Showa-machi, Maebashi, 371-0034, Japan.
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Burgdorf C, Dendorfer A, Kurz T, Schömig E, Stölting I, Schütte F, Richardt G. Role of Neuronal KATP Channels and Extraneuronal Monoamine Transporter on Norepinephrine Overflow in a Model of Myocardial Low Flow Ischemia. J Pharmacol Exp Ther 2004; 309:42-8. [PMID: 14718578 DOI: 10.1124/jpet.103.059832] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Global myocardial low flow ischemia results in an uniform suppression of norepinephrine (NE) overflow from the heart. We hypothesized that opening of neuronal ATP-sensitive potassium (K(ATP)) channels as well as activation of the extraneuronal monoamine transporter (EMT) mediates attenuation of NE overflow during low flow ischemia. Isolated rat hearts were subjected to low coronary flow of 0.4 ml min(-1). Release of endogenous NE was induced by electrical field stimulation. EMT activity was measured as the transport rate of the substrate N-[methyl-3H]4-phenylpyridinium ([3H]MPP+). NE overflow decreased by 57 +/- 2% within 120 min of low flow. Five minutes of reperfusion at normal flow (8 ml min(-1)) restored NE overflow to baseline. K(ATP) channel blockade with glibenclamide as well as EMT blockade with corticosterone increased NE overflow 1.5- and 2-fold at 120 min of low flow, whereas neither drug affected NE overflow in the absence of flow reduction. At normal flow, K(ATP) channel opening with cromakalim suppressed NE overflow, both in the presence and absence of EMT blockade (14 +/- 4 and 9 +/- 1%). However, cromakalim had no effect on EMT activity as indicated by an unaffected [3H]MPP+ overflow. In conclusion, activation of both K(ATP) channels and EMT mediate suppression of NE overflow during low flow ischemia. K(ATP) channels impair NE release directly at presynaptic nerve endings, whereas EMT increases NE elimination in a manner independent of K(ATP) channels.
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Affiliation(s)
- Christof Burgdorf
- Institut für experimentelle und klinische Pharmakologie und Toxikologie, Universitätsklinikum Schleswig-Holstein, Campus Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany.
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Ito H, Hayashi I, Izumi T, Majima M. Bradykinin inhibits development of myocardial infarction through B2 receptor signalling by increment of regional blood flow around the ischaemic lesions in rats. Br J Pharmacol 2003; 138:225-33. [PMID: 12522094 PMCID: PMC1573639 DOI: 10.1038/sj.bjp.0705013] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1 To identify the roles of endogenous kinins in prevention of myocardial infarction (MI), we performed the permanent ligation of coronary artery in rats. 2 The size of MI 12, 24, and 48 h after coronary ligation in kininogen-deficient Brown Norway Katholiek (BN-Ka) rats was significantly larger (49.7+/-0.2%, 49.6+/-2%, and 51.1+/-1%, respectively) than that of kinin-replete Brown Norway Kitasato (BN-Ki) rats (42+/-2%, 38.5+/-4%, and 41.5+/-1%). 3 Hoe140, a bradykinin (BK) B(2) receptor antagonist injected (1.0 mg kg(-1), i.v.) half an hour before, and every 8 h after, coronary ligation, significantly increased the size of MI in Sprague-Dawley rats. Aprotinin, a kallikrein inhibitor, which was infused intravenously (10,000 Units kg(-1) h(-1)) with an osmotic mini-pump, significantly increased the size of an MI 24 h after ligation. 4 When evaluated using microspheres, the regional myocardial blood flow around the necrotic lesion in BN-Ka rats 6 h after ligation was reduced more than that in BN-Ki rats with MI by 41-46%. The same was true in Hoe140-treated BN-Ki rats. 5 FR190997, a nonpeptide B(2) agonist, which was infused (10 microg kg(-1) h(-1)) into the vena cava of BN-Ka rats for 24 h with an osmotic mini-pump, caused significant reduction in the size of MI (38+/-3%), in comparison with the size in vehicle solution-treated rats (51+/-3%). The size of MI in FR190997-treated BN-Ka rats was the same as in BN-Ki rats. 6 These results suggested that endogenous kinin has the capacity to reduce the size of MI via B(2) receptor signalling because of the increase in regional myocardial blood flow around the ischaemic lesion.
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Affiliation(s)
- Hiroshi Ito
- Department of Pharmacology, Kitasato University School of Medicine, Kitasato 1-15-1, Sagamihara, Kanagawa 228-8555, Japan
- Department of Internal Medicine, Kitasato University School of Medicine, Kitasato 1-15-1, Sagamihara, Kanagawa 228-8555, Japan
| | - Izumi Hayashi
- Department of Pharmacology, Kitasato University School of Medicine, Kitasato 1-15-1, Sagamihara, Kanagawa 228-8555, Japan
| | - Tohru Izumi
- Department of Internal Medicine, Kitasato University School of Medicine, Kitasato 1-15-1, Sagamihara, Kanagawa 228-8555, Japan
| | - Masataka Majima
- Department of Pharmacology, Kitasato University School of Medicine, Kitasato 1-15-1, Sagamihara, Kanagawa 228-8555, Japan
- Author for correspondence:
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Chiari P, Piriou V, Hadour G, Rodriguez C, Loufouat J, Lehot JJ, Ovize M, Ferrera R. Preservation of ischemia and isoflurane-induced preconditioning after brain death in rabbit hearts. Am J Physiol Heart Circ Physiol 2002; 283:H1769-74. [PMID: 12384453 DOI: 10.1152/ajpheart.00361.2002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We sought to determine whether brain death-induced catecholamine release preconditions the heart, and if not, whether it precludes further protection by repetitive ischemia or isoflurane. Anesthetized rabbits underwent 30 min of coronary occlusion and 4 h of reperfusion. The effect on infarct size of either no intervention (controls), ischemic preconditioning (IPC), or isoflurane inhalation (Iso) was evaluated with or without previous brain death (BD) induced by subdural balloon inflation. Plasma catecholamine levels were measured at several time points. Although it dramatically increase plasma catecholamine levels, BD failed to reduce infarct size that averaged 0.49 +/- 0.34 without BD versus 0.45 +/- 0.27 g with BD. IPC and Iso, alone as well as after BD, significantly reduced infarct size that averaged 0.11 +/- 0.04, 0.21 +/- 0.15, 0.10 +/- 0.09, and 0.22 +/- 0.10 g in IPC, Iso, BD + IPC, and BD + Iso groups, respectively (means +/- SD, P < 0.05 vs. controls). BD-induced catecholamines "storm" does not precondition the rabbit heart that however retains the ability to be protected by repetition of brief ischemia or isoflurane inhalation.
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Affiliation(s)
- Pascal Chiari
- Service d'Anesthésie Réanimation, Hôpital Cardiologique Louis Pradel, BP Lyon-Montchat, 69394 Lyon Cedex 03, France.
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Sakai K, Yamagata T, Teragawa H, Matsuura H, Chayama K. Nicorandil enhances myocardial tolerance to ischemia without progressive collateral recruitment during coronary angioplasty. Circ J 2002; 66:317-22. [PMID: 11954943 DOI: 10.1253/circj.66.317] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Nicorandil, a hybrid nitrate and ATP-sensitive potassium channel opener, has had a preconditioning effect in some coronary angioplasty studies. The present study investigated whether the cardioprotective effects of nicorandil involve coronary collateral function. Thirty-two patients with stable angina pectoris were randomized to receive a 1-min intravenous infusion of nicorandil (100 microg/kg) or normal saline. Five minutes later they underwent three 2-min balloon inflations 5-min apart. The maximum ST-segment elevation (deltaSTmax), the sum of ST-segment elevations in all leads (sigmaST), and the chest pain score were determined at the end of each balloon inflation. The collateral flow index (CFI) was derived from simultaneous measurement of the mean aortic pressure and the coronary wedge pressure obtained from a pressure guidewire during balloon inflation. The deltaSTmax, sigmaST, and chest pain score decreased progressively during the 3 sequential balloon inflations in both groups, and the deltaSTmax and sigmaST were less in the nicorandil group than in the control group during each inflation. The CFI did not change during the 3 inflations in either group and was similar in the 2 groups during each inflation. In conclusion, pretreatment with intravenous nicorandil enhances myocardial tolerance to ischemia without progressive collateral recruitment during coronary angioplasty.
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Affiliation(s)
- Kenya Sakai
- The First Department of Internal Medicine, Hiroshima University School of Medicine, Japan
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