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Saporin as a Commercial Reagent: Its Uses and Unexpected Impacts in the Biological Sciences—Tools from the Plant Kingdom. Toxins (Basel) 2022; 14:toxins14030184. [PMID: 35324681 PMCID: PMC8952126 DOI: 10.3390/toxins14030184] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 02/23/2022] [Accepted: 02/23/2022] [Indexed: 02/02/2023] Open
Abstract
Saporin is a ribosome-inactivating protein that can cause inhibition of protein synthesis and causes cell death when delivered inside a cell. Development of commercial Saporin results in a technology termed ‘molecular surgery’, with Saporin as the scalpel. Its low toxicity (it has no efficient method of cell entry) and sturdy structure make Saporin a safe and simple molecule for many purposes. The most popular applications use experimental molecules that deliver Saporin via an add-on targeting molecule. These add-ons come in several forms: peptides, protein ligands, antibodies, even DNA fragments that mimic cell-binding ligands. Cells that do not express the targeted cell surface marker will not be affected. This review will highlight some newer efforts and discuss significant and unexpected impacts on science that molecular surgery has yielded over the last almost four decades. There are remarkable changes in fields such as the Neurosciences with models for Alzheimer’s Disease and epilepsy, and game-changing effects in the study of pain and itch. Many other uses are also discussed to record the wide-reaching impact of Saporin in research and drug development.
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2
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Zheng L, Sun W, Qiao Y, Hou B, Guo J, Killu A, Yao Y. Symptomatic Premature Ventricular Contractions in Vasovagal Syncope Patients: Autonomic Modulation and Catheter Ablation. Front Physiol 2021; 12:653225. [PMID: 34012407 PMCID: PMC8126685 DOI: 10.3389/fphys.2021.653225] [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: 01/14/2021] [Accepted: 04/13/2021] [Indexed: 11/13/2022] Open
Abstract
Introduction There has been limited reports about the comorbid premature ventricular contractions (PVCs) and vasovagal syncope (VVS). Deceleration capacity (DC) was demonstrated to be a quantitative evaluation to assess the cardiac vagal activity. This study sought to report the impact of autonomic modulation on symptomatic PVCs in VVS patients. Methods and Results Twenty-six VVS patients with symptomatic idiopathic PVCs were consecutively enrolled. Identification and catheter ablation of left atrial ganglionated plexi (GP) and PVCs were performed in 26 and 20 patients, respectively. Holter 24 h-electrocardiograms were performed before and after the procedure to evaluate DC and PVCs occurrence. Eighteen patients were subtyped as DC-dependent PVCs (D-PVCs) and eight as DC-independent PVCs groups (I-PVCs). In D-PVCs group, circadian rhythm of hourly PVCs was positively correlated with hourly DC (P < 0.05) while there was no correlation in I-PVCs group (P > 0.05). Fifty-three GPs with positive vagal response were successfully elicited (2.0 ± 0.8 per patient). PVCs failed to occur spontaneously nor to be induced in six patients. In the remaining 20 patients, PVCs foci identified were all located in the ventricular outflow tract region. Post-ablation DC decreased significantly from baseline (P < 0.05). During mean follow-up of 10.64 ± 6.84 months, syncope recurred in one patient and PVCs recurred in another. PVCs burden of the six patients in whom neither catheter ablation nor antiarrhythmic drugs were applied demonstrated a significant decrease during follow-up (P = 0.037). Conclusion Autonomic activities were involved in the occurrence of symptomatic idiopathic PVCs in some VVS patients. D-PVCs might be facilitated by increased vagal activities. Catheter ablation of GP and PVCs foci may be an effective, safe treatment in patients with concomitant VVS and idiopathic PVCs.
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Affiliation(s)
- Lihui Zheng
- Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Wei Sun
- Department of General Medicine, Monash Health, Melbourne, VIC, Australia
| | - Yu Qiao
- Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Bingbo Hou
- Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jinrui Guo
- Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Ammar Killu
- Department of Cardiovascular Disease, Mayo Clinic, Rochester, MN, United States
| | - Yan Yao
- Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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3
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Fu LW, Tjen-A-Looi SC, Barvarz S, Guo ZL, Malik S. Role of opioid receptors in modulation of P2X receptor-mediated cardiac sympathoexcitatory reflex response. Sci Rep 2019; 9:17224. [PMID: 31748569 PMCID: PMC6868205 DOI: 10.1038/s41598-019-53754-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 10/31/2019] [Indexed: 01/15/2023] Open
Abstract
Myocardial ischemia evokes powerful reflex responses through activation of vagal and sympathetic afferents in the heart through the release of ischemic metabolites. We have demonstrated that extracellular ATP stimulates cardiac sympathetic afferents through P2 receptor-mediated mechanism, and that opioid peptides suppress these afferents' activity. However, the roles of both P2 receptor and endogenous opioids in cardiac sympathoexcitatory reflex (CSR) responses remain unclear. We therefore hypothesized that activation of cardiac P2 receptor evokes CSR responses by stimulating cardiac sympathetic afferents and these CSR responses are modulated by endogenous opioids. We observed that intrapericardial injection of α,β-methylene ATP (α,β-meATP, P2X receptor agonist), but not ADP (P2Y receptor agonist), caused a graded increase in mean arterial pressure in rats with sinoaortic denervation and vagotomy. This effect of α,β-meATP was abolished by blockade of cardiac neural transmission with intrapericardial procaine treatment and eliminated by intrapericardial A-317491, a selective P2X2/3 and P2X3 receptor antagonist. Intrapericardial α,β-meATP also evoked CSR response in vagus-intact rats. Furthermore, the P2X receptor-mediated CSR responses were enhanced by intrapericardial naloxone, a specific opioid receptor antagonist. These data suggest that stimulation of cardiac P2X2/3 and P2X3, but not P2Y receptors, powerfully evokes CSR responses through activation of cardiac spinal afferents, and that endogenous opioids suppress the P2X receptor-mediated CSR responses.
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Affiliation(s)
- Liang-Wu Fu
- Susan Samueli Integrative Health Institute and Department of Medicine, School of Medicine, University of California at Irvine, Irvine, CA, 92697, USA.
| | - Stephanie C Tjen-A-Looi
- Susan Samueli Integrative Health Institute and Department of Medicine, School of Medicine, University of California at Irvine, Irvine, CA, 92697, USA
| | - Sherwin Barvarz
- Susan Samueli Integrative Health Institute and Department of Medicine, School of Medicine, University of California at Irvine, Irvine, CA, 92697, USA
| | - Zhi-Ling Guo
- Susan Samueli Integrative Health Institute and Department of Medicine, School of Medicine, University of California at Irvine, Irvine, CA, 92697, USA
| | - Shaista Malik
- Susan Samueli Integrative Health Institute and Department of Medicine, School of Medicine, University of California at Irvine, Irvine, CA, 92697, USA
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4
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Xiong L, Liu Y, Zhou M, Wang G, Quan D, Shen C, Shuai W, Kong B, Huang C, Huang H. Targeted ablation of cardiac sympathetic neurons improves ventricular electrical remodelling in a canine model of chronic myocardial infarction. Europace 2019; 20:2036-2044. [PMID: 29860489 DOI: 10.1093/europace/euy090] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 04/05/2018] [Indexed: 12/25/2022] Open
Abstract
Aims The purpose of this study was to evaluate the cardiac electrophysiologic effects of targeted ablation of cardiac sympathetic neurons (TACSN) in a canine model of chronic myocardial infarction (MI). Methods and results Thirty-eight anaesthetized dogs were randomly assigned into the sham-operated, MI, and MI-TACSN groups, respectively. Myocardial infarction-targeted ablation of cardiac sympathetic neuron was induced by injecting cholera toxin B subunit-saporin compound in the left stellate ganglion (LSG). Five weeks after surgery, the cardiac function, heart rate variability (HRV), ventricular electrophysiological parameters, LSG function and neural activity, serum norepinephrine (NE), nerve growth factor (NGF), and brain natriuretic peptide (BNP) levels were measured. Cardiac sympathetic innervation was determined with immunofluorescence staining of growth associated protein-43 (GAP43) and tyrosine hydroxylase (TH). Compared with MI group, TACSN significantly improved HRV, attenuated LSG function and activity, prolonged corrected QT interval, decreased Tpeak-Tend interval, prolonged ventricular effective refractory period (ERP), and action potential duration (APD), decreased the slopes of APD restitution curves, suppressed the APD alternans, increased ventricular fibrillation threshold, and reduced serum NE, NGF, and BNP levels. Moreover, the densities of GAP43 and TH-positive nerve fibres in the infarcted border zone in the MI-TACSN group were lower than those in the MI group. Conclusion Targeted ablation of cardiac sympathetic neuron attenuates sympathetic remodelling and improves ventricular electrical remodelling in the chronic phase of MI. These data suggest that TACSN may be a novel approach to treating ventricular arrhythmias.
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Affiliation(s)
- Liang Xiong
- Department of Cardiology, Renmin Hospital of Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Cardiovascular Research Institute, Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Hubei Key Laboratory of Cardiology, No.238 Jiefang Road, Wuchang, Wuhan, China
| | - Yu Liu
- Department of Cardiology, Renmin Hospital of Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Cardiovascular Research Institute, Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Hubei Key Laboratory of Cardiology, No.238 Jiefang Road, Wuchang, Wuhan, China
| | - Mingmin Zhou
- Department of Cardiology, Renmin Hospital of Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Cardiovascular Research Institute, Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Hubei Key Laboratory of Cardiology, No.238 Jiefang Road, Wuchang, Wuhan, China
| | - Guangji Wang
- Department of Cardiology, Renmin Hospital of Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Cardiovascular Research Institute, Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Hubei Key Laboratory of Cardiology, No.238 Jiefang Road, Wuchang, Wuhan, China
| | - Dajun Quan
- Department of Cardiology, Renmin Hospital of Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Cardiovascular Research Institute, Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Hubei Key Laboratory of Cardiology, No.238 Jiefang Road, Wuchang, Wuhan, China
| | - Caijie Shen
- Department of Cardiology, Renmin Hospital of Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Cardiovascular Research Institute, Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Hubei Key Laboratory of Cardiology, No.238 Jiefang Road, Wuchang, Wuhan, China
| | - Wei Shuai
- Department of Cardiology, Renmin Hospital of Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Cardiovascular Research Institute, Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Hubei Key Laboratory of Cardiology, No.238 Jiefang Road, Wuchang, Wuhan, China
| | - Bin Kong
- Department of Cardiology, Renmin Hospital of Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Cardiovascular Research Institute, Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Hubei Key Laboratory of Cardiology, No.238 Jiefang Road, Wuchang, Wuhan, China
| | - Congxin Huang
- Department of Cardiology, Renmin Hospital of Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Cardiovascular Research Institute, Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Hubei Key Laboratory of Cardiology, No.238 Jiefang Road, Wuchang, Wuhan, China
| | - He Huang
- Department of Cardiology, Renmin Hospital of Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Cardiovascular Research Institute, Wuhan University, No.238 Jiefang Road, Wuchang, Wuhan, China.,Hubei Key Laboratory of Cardiology, No.238 Jiefang Road, Wuchang, Wuhan, China
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5
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Koza Y, Bayram E, Aydin MD, Atalay C, Onen MR, Ozturk C, Sipal S, Demirci E, Levent A. Predictive Role of the Cervical Sympathetic Trunk Ischemia on Lower Heart Rates in an Experimentally Induced Stenoocclusive Carotid Artery Model by Bilateral Common Carotid Artery Ligation. Cardiovasc Toxicol 2018; 19:56-61. [DOI: 10.1007/s12012-018-9473-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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6
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Liu S, Yu X, Luo D, Qin Z, Wang X, He W, Ma R, Hu H, Xie J, He B, Lu Z, Jiang H. Ablation of the Ligament of Marshall and Left Stellate Ganglion Similarly Reduces Ventricular Arrhythmias During Acute Myocardial Infarction. Circ Arrhythm Electrophysiol 2018; 11:e005945. [PMID: 29700056 DOI: 10.1161/circep.117.005945] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 03/12/2018] [Indexed: 01/09/2023]
Abstract
Background:
Sympathetic denervation exerts protective effects against ventricular arrhythmias (VAs) induced by acute myocardial infarction. The results of a previous study indicated that the distal part of the ligament of Marshall (LOM
LSPV
) might be a sympathetic conduit between the left stellate ganglion (LSG) and the ventricles. The present study was designed to compare the effects between LSG and LOM
LSPV
ablation on ischemia-induced VAs.
Methods:
Twenty-nine dogs were randomly divided into sham ablation group (group 1, n=9), LOM
LSPV
ablation group (group 2, n=10), and LSG ablation group (group 3, n=10). Ablation was performed before occlusion of the left anterior coronary artery. Changes in the heart rate variability, serum norepinephrine, ventricular effective refractory period, and blood pressure induced by LSG stimulation were observed, and the occurrence of VAs was recorded. Immunostaining examinations of LOM
LSPV
were performed in dogs without ablation.
RESULTS:
In group 2, LOM
LSPV
ablation evidently attenuated blood pressure elevation induced by LSG stimulation. Both LOM
LSPV
ablation and LSG ablation similarly prolonged ventricular effective refractory period and reduced the concentration of serum norepinephrine, the sympathetic index of heart rate variability, and the incidence of VAs compared with sham ablation. Abundant sympathetic nerve fibers were observed in LOM
LSPV
.
Conclusions:
LOM
LSPV
ablation prevented acute myocardial infarction–induced VAs with the same efficiency as LSG ablation, potentially by blocking the sympathetic pathway from the LSG to the heart.
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Affiliation(s)
- Shan Liu
- Department of Cardiology, Renmin Hospital of Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Cardiovascular Research Institute, Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Hubei Key Laboratory of Cardiology, Wuhan, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
| | - Xiaomei Yu
- Department of Cardiology, Renmin Hospital of Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Cardiovascular Research Institute, Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Hubei Key Laboratory of Cardiology, Wuhan, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
| | - Da Luo
- Department of Cardiology, Renmin Hospital of Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Cardiovascular Research Institute, Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Hubei Key Laboratory of Cardiology, Wuhan, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
| | - Zhiliang Qin
- Department of Cardiology, Renmin Hospital of Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Cardiovascular Research Institute, Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Hubei Key Laboratory of Cardiology, Wuhan, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
| | - Xiaoying Wang
- Department of Cardiology, Renmin Hospital of Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Cardiovascular Research Institute, Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Hubei Key Laboratory of Cardiology, Wuhan, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
| | - Wenbo He
- Department of Cardiology, Renmin Hospital of Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Cardiovascular Research Institute, Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Hubei Key Laboratory of Cardiology, Wuhan, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
| | - Ruisong Ma
- Department of Cardiology, Renmin Hospital of Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Cardiovascular Research Institute, Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Hubei Key Laboratory of Cardiology, Wuhan, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
| | - Huihui Hu
- Department of Cardiology, Renmin Hospital of Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Cardiovascular Research Institute, Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Hubei Key Laboratory of Cardiology, Wuhan, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
| | - Jing Xie
- Department of Cardiology, Renmin Hospital of Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Cardiovascular Research Institute, Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Hubei Key Laboratory of Cardiology, Wuhan, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
| | - Bo He
- Department of Cardiology, Renmin Hospital of Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Cardiovascular Research Institute, Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Hubei Key Laboratory of Cardiology, Wuhan, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
| | - Zhibing Lu
- Department of Cardiology, Renmin Hospital of Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Cardiovascular Research Institute, Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Hubei Key Laboratory of Cardiology, Wuhan, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Department of Cardiology, Huangshi Central Hospital, Hubei Polytechnic University, China (Z.L.)
| | - Hong Jiang
- Department of Cardiology, Renmin Hospital of Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Cardiovascular Research Institute, Wuhan University, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
- Hubei Key Laboratory of Cardiology, Wuhan, China (S.L., X.Y., D.L., Z.Q., X.W., W.H., R.M., H.H., J.X., B.H., Z.L., H.J.)
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7
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Lujan HL, DiCarlo SE. Fundamental hemodynamic mechanisms mediating the response to myocardial ischemia in conscious paraplegic mice: cardiac output versus peripheral resistance. Physiol Rep 2017; 5:5/6/e13214. [PMID: 28336819 PMCID: PMC5371571 DOI: 10.14814/phy2.13214] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 02/21/2017] [Accepted: 02/22/2017] [Indexed: 11/25/2022] Open
Abstract
Autonomic dysfunction, a relative sedentary lifestyle, a reduced muscle mass and increased adiposity leads to metabolic abnormalities that accelerate the development of coronary artery disease (CAD) in individuals living with spinal cord injury (SCI). An untoward cardiac incident is related to the degree of CAD, suggesting that the occurrence of a significant cardiac event is significantly higher for individuals with SCI. Thus, understanding the fundamental hemodynamic mechanisms mediating the response to myocardial ischemia has the potential to positively impact individuals and families living with SCI. Accordingly, we systematically investigated if thoracic level 5 spinal cord transection (T5X; paraplegia) alters the arterial blood pressure response to coronary artery occlusion and if the different arterial blood pressure responses to coronary artery occlusion between intact and paraplegic mice are mediated by changes in cardiac output and or systemic peripheral resistance and whether differences in cardiac output are caused by changes in heart rate and or stroke volume. To achieve this goal, the tolerance to 3 min of coronary artery occlusion was determined in conscious intact and paraplegic mice. Paraplegic mice had an impaired ability to maintain arterial blood pressure during coronary artery occlusion as arterial pressure fell to near lethal levels by 1.38 ± 0.64 min. The lower arterial pressure was mediated by a lower cardiac output as systemic peripheral resistance was elevated in paraplegic mice. The lower cardiac output was mediated by a reduced heart rate and stroke volume. These results indicate that in paraplegic mice, the arterial pressure response to coronary artery occlusion is hemodynamically mediated primarily by cardiac output which is determined by heart rate and stroke volume.
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Affiliation(s)
- Heidi L Lujan
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan
| | - Stephen E DiCarlo
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan
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8
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Hundahl LA, Tfelt-Hansen J, Jespersen T. Rat Models of Ventricular Fibrillation Following Acute Myocardial Infarction. J Cardiovasc Pharmacol Ther 2017; 22:514-528. [PMID: 28381093 DOI: 10.1177/1074248417702894] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A number of animal models have been designed in order to unravel the underlying mechanisms of acute ischemia-induced arrhythmias and to test compounds and interventions for antiarrhythmic therapy. This is important as acute myocardial infarction (AMI) continues to be the major cause of sudden cardiac death, and we are yet to discover safe and effective treatments of the lethal arrhythmias occurring in the acute setting. Animal models therefore continue to be relevant for our understanding and treatment of acute ischemic arrhythmias. This review discusses the applicability of the rat as a model for ventricular arrhythmias occurring during the acute phase of AMI. It provides a description of models developed, advantages and disadvantages of rats, as well as an overview of the most important interventions investigated and the relevance for human pathophysiology.
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Affiliation(s)
- Laura A Hundahl
- 1 Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jacob Tfelt-Hansen
- 2 Department of Cardiology, Heart Centre, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Thomas Jespersen
- 1 Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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9
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Abstract
Cardiac control is mediated via a series of reflex control networks involving somata in the (i) intrinsic cardiac ganglia (heart), (ii) intrathoracic extracardiac ganglia (stellate, middle cervical), (iii) superior cervical ganglia, (iv) spinal cord, (v) brainstem, and (vi) higher centers. Each of these processing centers contains afferent, efferent, and local circuit neurons, which interact locally and in an interdependent fashion with the other levels to coordinate regional cardiac electrical and mechanical indices on a beat-to-beat basis. This control system is optimized to respond to normal physiological stressors (standing, exercise, and temperature); however, it can be catastrophically disrupted by pathological events such as myocardial ischemia. In fact, it is now recognized that autonomic dysregulation is central to the evolution of heart failure and arrhythmias. Autonomic regulation therapy is an emerging modality in the management of acute and chronic cardiac pathologies. Neuromodulation-based approaches that target select nexus points of this hierarchy for cardiac control offer unique opportunities to positively affect therapeutic outcomes via improved efficacy of cardiovascular reflex control. As such, understanding the anatomical and physiological basis for such control is necessary to implement effectively novel neuromodulation therapies. © 2016 American Physiological Society. Compr Physiol 6:1635-1653, 2016.
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Affiliation(s)
- Jeffrey L Ardell
- Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, University of California, Los Angeles, California, USA.,UCLA Neurocardiology Research Center of Excellence, David Geffen School of Medicine, Los Angeles, California, USA
| | - John Andrew Armour
- Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, University of California, Los Angeles, California, USA.,UCLA Neurocardiology Research Center of Excellence, David Geffen School of Medicine, Los Angeles, California, USA
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Ardell JL, Andresen MC, Armour JA, Billman GE, Chen PS, Foreman RD, Herring N, O'Leary DS, Sabbah HN, Schultz HD, Sunagawa K, Zucker IH. Translational neurocardiology: preclinical models and cardioneural integrative aspects. J Physiol 2016; 594:3877-909. [PMID: 27098459 DOI: 10.1113/jp271869] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 03/14/2016] [Indexed: 12/15/2022] Open
Abstract
Neuronal elements distributed throughout the cardiac nervous system, from the level of the insular cortex to the intrinsic cardiac nervous system, are in constant communication with one another to ensure that cardiac output matches the dynamic process of regional blood flow demand. Neural elements in their various 'levels' become differentially recruited in the transduction of sensory inputs arising from the heart, major vessels, other visceral organs and somatic structures to optimize neuronal coordination of regional cardiac function. This White Paper will review the relevant aspects of the structural and functional organization for autonomic control of the heart in normal conditions, how these systems remodel/adapt during cardiac disease, and finally how such knowledge can be leveraged in the evolving realm of autonomic regulation therapy for cardiac therapeutics.
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Affiliation(s)
- J L Ardell
- University of California - Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, Los Angeles, CA, USA.,UCLA Neurocardiology Research Center of Excellence, David Geffen School of Medicine, Los Angeles, CA, USA
| | - M C Andresen
- Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR, USA
| | - J A Armour
- University of California - Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, Los Angeles, CA, USA.,UCLA Neurocardiology Research Center of Excellence, David Geffen School of Medicine, Los Angeles, CA, USA
| | - G E Billman
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, OH, USA
| | - P-S Chen
- The Krannert Institute of Cardiology and Division of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - R D Foreman
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - N Herring
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - D S O'Leary
- Department of Physiology, Wayne State University, Detroit, MI, USA
| | - H N Sabbah
- Department of Medicine, Henry Ford Hospital, Detroit, MI, USA
| | - H D Schultz
- Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - K Sunagawa
- Department of Cardiovascular Medicine, Kyushu University, Fukuoka, Japan
| | - I H Zucker
- Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, USA
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11
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Zhang L, Lu Y, Sun J, Zhou X, Tang B. Subthreshold vagal stimulation suppresses ventricular arrhythmia and inflammatory response in a canine model of acute cardiac ischaemia and reperfusion. Exp Physiol 2015; 101:41-9. [PMID: 26553757 DOI: 10.1113/ep085518] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 11/05/2015] [Indexed: 12/24/2022]
Affiliation(s)
- Ling Zhang
- Department of Cardiology, First Affiliated Hospital; Xinjiang Medical University; Urumqi 830054 China
| | - Yanmei Lu
- Department of Cardiology, First Affiliated Hospital; Xinjiang Medical University; Urumqi 830054 China
| | - Juan Sun
- Department of Cardiology, First Affiliated Hospital; Xinjiang Medical University; Urumqi 830054 China
| | - Xianhui Zhou
- Department of Cardiology, First Affiliated Hospital; Xinjiang Medical University; Urumqi 830054 China
| | - Baopeng Tang
- Department of Cardiology, First Affiliated Hospital; Xinjiang Medical University; Urumqi 830054 China
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12
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Yang LC, Zhang PP, Chen XM, Li CY, Sun J, Hou JW, Chen RH, Wang YP, Li YG. Semaphorin 3a transfection into the left stellate ganglion reduces susceptibility to ventricular arrhythmias after myocardial infarction in rats. Europace 2015; 18:1886-1896. [PMID: 26541708 DOI: 10.1093/europace/euv276] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 07/06/2015] [Indexed: 02/01/2023] Open
Abstract
AIMS Myocardial infarction (MI) induces neural remodelling of the left stellate ganglion (LSG), which may contribute to ischaemia-induced arrhythmias. The neural chemorepellent Semaphorin 3a (Sema3a) has been identified as a negative regulator of sympathetic innervation in the LSG and heart. We previously reported that overexpression of Sema3a in the border zone could reduce the arrhythmogenic effects of cardiac sympathetic hyperinnervation post-MI. This study investigated whether Sema3a overexpression within the LSG confers an antiarrhythmic effect after MI through decreasing extra- and intra-cardiac neural remodelling. METHODS AND RESULTS Sprague-Dawley rats were subjected to MI, and randomly allocated to intra-LSG microinjection of either phosphate-buffered saline (PBS), adenovirus encoding green fluorescent protein (AdGFP), or adenovirus encoding Sema3a (AdSema3a). Sham-operated rats served as controls. Two weeks after infarction, MI-induced nerve sprouting and sympathetic hyperinnervation in the LSG and myocardium were significantly attenuated by intra-LSG injection with AdSema3a, as assessed by immunohistochemistry and western blot analysis of growth-associated protein 43 and tyrosine hydroxylase. This was also confirmed by sympathetic nerve function changes assessed by cardiac norepinephrine content. Additionally, intra-LSG injection with AdSema3a alleviated MI-induced accumulation of dephosphorylated connexin 43 in the infarct border zone. Furthermore, Sema3a overexpression in the LSG reduced the incidence of inducible ventricular tachyarrhythmia by programmed electrical stimulation post-MI, and arrhythmia scores were significantly lower in the AdSema3a group than in the PBS and AdGFP groups. CONCLUSION Semaphorin 3a overexpression in the LSG ameliorates the inducibility of ventricular arrhythmias after MI, mainly through attenuation of neural remodelling within the cardiac-neuraxis.
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Affiliation(s)
- Ling-Chao Yang
- Department of Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China
| | - Peng-Pai Zhang
- Department of Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China
| | - Xiao-Meng Chen
- Department of Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China
| | - Chang-Yi Li
- Department of Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China
| | - Jian Sun
- Department of Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China
| | - Jian-Wen Hou
- Department of Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China
| | - Ren-Hua Chen
- Department of Cardiology, Ganzhou People Hospital, Ganzhou Hospital Affiliated to Nanchang University, Ganzhou, Jiangxi 341000, China
| | - Yue-Peng Wang
- Department of Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China
| | - Yi-Gang Li
- Department of Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China
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13
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Targeted ablation of cardiac sympathetic neurons: A promising approach to prevent sudden cardiac death. Int J Cardiol 2015; 202:425-6. [PMID: 26433164 DOI: 10.1016/j.ijcard.2015.09.049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 09/19/2015] [Indexed: 11/22/2022]
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Huang B, Yu L, He B, Wang S, Lu Z, Liao K, Wang Z, Zhou X, He W, Jiang H. Sympathetic denervation of heart and kidney induces similar effects on ventricular electrophysiological properties. EUROINTERVENTION 2015; 11:598-604. [DOI: 10.4244/eijv11i5a119] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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15
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Prevention of ventricular arrhythmia complicating acute myocardial infarction by local cardiac denervation. Int J Cardiol 2015; 184:667-673. [PMID: 25771236 DOI: 10.1016/j.ijcard.2015.03.057] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 12/27/2014] [Accepted: 03/03/2015] [Indexed: 11/22/2022]
Abstract
BACKGROUND Augmentation of sympathetic nerve activity after acute myocardial infarction (AMI) contributes to fatal arrhythmia. In this study, we investigated whether local ablation of the coronary sinus (CS) and great cardiac vein (GCV) peripheral nerves could reduce ventricular arrhythmias (VA) in a canine AMI model. METHODS Twenty-one anesthetized dogs were randomly assigned into the sham-operated, MI and MI-ablation groups, respectively. The incidence and duration of VA were monitored among different groups. The ventricular effective refractory period (ERP), the ERP dispersion and the ventricular fibrillation threshold (VFT) were measured during the experiments. Norepinephrine (NE) levels in CS blood and cardiac tissue were also detected in this study. RESULTS The incidence and duration of VA in MI-ablation group were significantly reduced as compared to the MI dogs (p<0.05). Furthermore, local cardiac denervation drastically prolonged the ventricular ERP in the ischemia area, decreased the ERP dispersion, and reduced NE levels in CS blood (P<0.05). VFT also showed an increased trend in the AMI-ablation group. CONCLUSIONS The results of this study indicate that, in the canine AMI model, local ablation of CS and GCV peripheral nerves reduces VA occurrence and improves ventricular electrical stability with no obvious effects on heart rate, mean arterial pressure and infarct size. This study suggests that local cardiac denervation may prevent ventricular arrhythmias complicating AMI.
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16
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Huang B, Yu L, Scherlag BJ, Wang S, He B, Yang K, Liao K, Lu Z, He W, Zhang L, Po SS, Jiang H. Left renal nerves stimulation facilitates ischemia-induced ventricular arrhythmia by increasing nerve activity of left stellate ganglion. J Cardiovasc Electrophysiol 2014; 25:1249-56. [PMID: 25066536 DOI: 10.1111/jce.12498] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 07/14/2014] [Accepted: 07/21/2014] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Renal sympathetic nerve (RSN) activity plays a key role in systemic sympathetic hyperactivity. Previous studies have shown that cardiac sympathetic hyperactivity, especially the left stellate ganglion (LSG), contributes to the pathogenesis of ventricular arrhythmias (VAs) after acute myocardial infarction (AMI). METHODS AND RESULTS Twenty-eight dogs received 3 hours of continuous left-sided electrical stimulation of RSN (LRS; Group-1, n = 9), sham RSN stimulation (Group-2, n = 9), or LSG ablation plus 3 hours of LRS (Group-3, n = 10) were included. AMI was induced by ligating the proximal left anterior descending coronary artery. LRS was performed using electrical stimulation on the adventitia of left renal artery at the voltage increasing the systolic blood pressure (BP) by 10%. BP, heart rate variability (HRV), serum norepinephrine (NE) level, and LSG function were measured at baseline and the end of each hour of LRS. C-fos and nerve growth factor (NGF) protein expressed in the LSG were examined in Group-1 and Group-2. Compared with baseline, 3 hours of LRS induced a significant increase in BP, sympathetic indices of HRV, serum NE level, and LSG function. The incidence of VAs in Group-1 was significantly higher than other groups. The expression of c-fos and NGF protein in the LSG was significantly higher in Group-1 than Group-2. CONCLUSION Three hours of LRS induces both systemic and cardiac sympathetic hyperactivity and increases the incidence of ischemia-induced VAs.
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Affiliation(s)
- Bing Huang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China
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Huang B, Yu L, He B, Lu Z, Wang S, He W, Yang K, Liao K, Zhang L, Jiang H. Renal sympathetic denervation modulates ventricular electrophysiology and has a protective effect on ischaemia-induced ventricular arrhythmia. Exp Physiol 2014; 99:1467-77. [PMID: 25172887 DOI: 10.1113/expphysiol.2014.082057] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Recently, a beneficial effect of renal sympathetic denervation (RSD) has been seen in patients with ventricular electrical storm. However, the effect of RSD on ventricular electrophysiology remains unclear. Thirty-three mongrel dogs were included in the present study. Renal sympathetic denervation was performed by radiofrequency ablation of the adventitial surface of the renal artery. In group 1 (n = 8), programmed stimulation was performed before and after RSD to determine the ventricular effective refractory period (ERP) and action potential duration (APD) restitution properties. The same parameters were measured in five other animals that underwent sham RSD to serve as controls. In group 2 (n = 10), acute myocardial ischaemia (AMI) was induced by ligating the proximal left anterior descending coronary artery after the performance of RSD, and the incidence of ventricular arrhythmia (VA) was calculated during 1 h of recording. In another 10 dogs (group 3), AMI was induced and VA was measured with sham RSD. In group 1, RSD significantly prolonged ventricular ERP and APD, reduced the maximal slope (Smax) of the restitution curve and suppressed APD alternans at each site. Renal sympathetic denervation also significantly decreased the spatial dispersion of ERP, APD and Smax. In the five control animals, no significant electrophysiological change was detected after sham RSD. The occurrence of spontaneous VA during 1 h of AMI in group 2 was significantly lower than that in group 3. These data suggest that RSD stabilizes ventricular electrophysiological properties in normal hearts and reduces the occurrence of VA in hearts experiencing AMI.
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Affiliation(s)
- Bing Huang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China
| | - Lilei Yu
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China
| | - Bo He
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China
| | - Zhibing Lu
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China
| | - Songyun Wang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China
| | - Wenbo He
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China
| | - Kang Yang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China
| | - Kai Liao
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China
| | - Ling Zhang
- Arrhythmia Research Laboratory, First Affiliated Hospital of Xinjiang Medical University, Urumqi, PR China
| | - Hong Jiang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China
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Dor-Haim H, Berenfeld O, Horowitz M, Lotan C, Swissa M. Reduced Ventricular Arrhythmogeneity and Increased Electrical Complexity in Normal Exercised Rats. PLoS One 2013; 8:e66658. [PMID: 23825553 PMCID: PMC3688953 DOI: 10.1371/journal.pone.0066658] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 05/09/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The mechanisms whereby aerobic training reduces the occurrence of sudden cardiac death in humans are not clear. We test the hypothesis that exercise-induced increased resistance to ventricular tachycardia and fibrillation (VT/VF) involve an intrinsic remodeling in healthy hearts. METHODS AND RESULTS Thirty rats were divided into a sedentary (CTRL, n = 16) and two exercise groups: short- (4 weeks, ST, n = 7) and long-term (8 weeks, LT, n = 7) trained groups. Following the exercise program hearts were isolated and studied in a Langendorff perfusion system. An S1-S2 pacing protocol was applied at the right ventricle to determine inducibility of VT/VF. Fast Fourier transforms were applied on ECG time-series. In-vivo measurements showed training-induced increase in aerobic capacity, heart-to-body weight ratio and a 50% low-to-high frequency ratio reduction in the heart rate variability (p<0.05). In isolated hearts the probability for VF decreased from 26.1±14.4 in CTRL to 13.9±14.1 and 6.7±8.5% in the ST and LT, respectively (p<0.05). Duration of VF also decreased from 19.0±5.7 in CTRL to 8.8±7.1 and 6.0±5.8 sec in ST and LT respectively (p<0.05). Moreover, the pacing current required for VF induction increased following exercise (2.9±1.7 vs. 5.4±2.1 and 8.5±0.9 mA, respectively; p<0.05). Frequency analysis of ECG revealed an exercise-induced VF transition from a narrow single peak spectrum at 17 Hz in CTRL to a broader range of peaks ranging between 8.8 and 22.5 Hz in the LT group (p<0.05). CONCLUSION Exercise in rats leads to reduced VF propensity associated with an intrinsic cardiac remodeling related to a broader spectral range and faster frequency components in the ECG.
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Affiliation(s)
- Horesh Dor-Haim
- Heart Institute, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Omer Berenfeld
- Center for Arrhythmia Research, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Michal Horowitz
- Department of Physiology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Chaim Lotan
- Heart Institute, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Moshe Swissa
- Cardiac Research Center, Kaplan Medical Center, Rehovot, Israel
- * E-mail:
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Gu Y, Wang L, Wang X, Tang Y, Cao F, Fang Y. Assessment of ventricular electrophysiological characteristics at periinfarct zone of postmyocardial infarction in rabbits following stellate ganglion block. J Cardiovasc Electrophysiol 2012; 23 Suppl 1:S29-35. [PMID: 22994966 DOI: 10.1111/j.1540-8167.2012.02437.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
UNLABELLED Assessment of Ventricular Electrophysiological Characteristics. INTRODUCTION The aim of this study was to investigate the characteristics of ventricular electrophysiology following stellate ganglion block (SGB) at periinfarct zone in rabbits with myocardial infarction (MI). METHODS AND RESULTS Sixty-four rabbits were randomly assigned to 2 groups: MI (n = 32), ligation of the anterior descending coronary and sham operation (SO) (n = 32), without coronary ligation. Both MI and SO groups were divided into 4 subgroups according to right or left SGB and corresponding control (n = 8, each). After 8 weeks, 90% of monophasic action potential duration (MAPD90) of epicardium, midmyocardium and endocardium, transmural dispersion of repolarization (TDR), effective refractory period (ERP), and ventricular fibrillation threshold (VFT) were measured at the infarct border zone (MI group) and corresponding zone (SO group) following SGB. For SGB, 0.5 mL of 0.25% bupivacaine was used. Compared with the corresponding control group, in both the MI and SO groups, left SGB (LSGB) prolonged the MAPD90 of the 3 layers, reduced TDR, and increased ERP and VFT (P < 0.05). However, right SGB (RSGB) shortened MAPD90, increased TDR, and reduced ERP and VFT (P < 0.05). CONCLUSION The results of this study demonstrate that LSGB can increase the electrophysiological stability of ventricular myocardium.
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Affiliation(s)
- Yongwei Gu
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, China
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Galetta F, Carpi A, Abraham N, Guidotti E, Russo MA, Camici M, Antonelli A, Franzoni F, Santoro G. Age related cardiovascular dysfunction and effects of physical activity. Front Biosci (Elite Ed) 2012; 4:2617-37. [PMID: 22652665 DOI: 10.2741/e570] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The aim of the present article is to review the principal pathogenetic pathways of age-related cardiovascular changes and the positive effects of physical activity on these changes as well as on related cardiovascular dysfunction. The ageing mechanisms reviewed have been grouped into reduced tolerance of oxidative stress, loss of cardiac stem cells, cardiovascular remodeling and impairment of neurovegetative control. New pathogenetic conditions and their tests are described (sirtuines, telomere length, heart rate variability). Age related cardiovascular changes predispose the individual to arterial hypertension, heart failure and arrythmia. A broad spectrum of tests are available to indentify and monitor the emerging cardiovascular dysfunction. Physical activity influences all age related cardiovascular mechanisms, improves cardiovascular function and even, at moderate intensity can reduce mortality and heart attack risk. It is likely that the translation of laboratory studies to humans will improve understanding and stimulate the use of physical activity to benefit cardiovascular patients.
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Affiliation(s)
- Fabio Galetta
- Department of Internal Medicine, University of Pisa, Pisa, Italy
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Lujan HL, Janbaih H, Feng HZ, Jin JP, DiCarlo SE. Myocardial ischemia, reperfusion, and infarction in chronically instrumented, intact, conscious, and unrestrained mice. Am J Physiol Regul Integr Comp Physiol 2012; 302:R1384-400. [PMID: 22538514 DOI: 10.1152/ajpregu.00095.2012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In the United States alone, the National Heart, Lung, and Blood Institute (NHLBI) has invested several hundred million dollars in pursuit of myocardial infarct-sparing therapies. However, due largely to methodological limitations, this investment has not produced any notable clinical application or cardioprotective therapy. Among the major methodological limitations is the reliance on animal models that do not mimic the clinical situation. In this context, the limited use of conscious animal models is of major concern. In fact, whenever possible, studies of cardiovascular physiology and pathophysiology should be conducted in conscious, complex models to avoid the complications associated with the use of anesthesia and surgical trauma. The mouse has significant advantages over other experimental models for the investigation of infarct-sparing therapies. The mouse is inexpensive, has a high throughput, and presents the ability of one to create genetically modified models. However, successful infarct-sparing therapies in anesthetized mice or isolated mouse hearts may not be successful in more complex models, including conscious mice. Accordingly, a conscious mouse model of myocardial ischemia and reperfusion has the potential to be of major importance for advancing the concepts and methods that drive the development of infarct-sparing therapies. Therefore, we describe, for the first time, the use of an intact, conscious, and unrestrained mouse model of myocardial ischemia-reperfusion and infarction. The conscious mouse model permits occlusion and reperfusion of the left anterior descending coronary artery in an intact, complex model free of the confounding influences of anesthetics and surgical trauma. This methodology may be adopted for advancing the concepts and ideas that drive cardiovascular research.
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Affiliation(s)
- Heidi L Lujan
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
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Orlova YA, Makarova GV, Mikhailova GV, Ageev FT. Heart rate reduction as a therapeutic goal: focus on primary prevention. КАРДИОВАСКУЛЯРНАЯ ТЕРАПИЯ И ПРОФИЛАКТИКА 2012. [DOI: 10.15829/1728-8800-2012-1-89-95] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Recently published studies have demonstrated a direct link between heart rate (HR) and prognosis across various populations and clinical groups, including elderly people, patients with arterial hypertension, myocardial infarction, and coronary artery stenting, overweight patients, or even young people with relatively low cardiovascular risk levels. HR is considered as an additional independent risk factor (RF) of cardiovascular disease (CVD). However, thus far, pharmaceutical HR reduction has been demonstrated to improve prognosis only in patients with coronary heart disease or chronic heart failure. The results in CVD-free patients have been contradictory. The review discusses the potential of different HR-reducing therapeutic regimens, as a part of primary CVD prevention.
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Affiliation(s)
- Yu. A. Orlova
- A.L. Myasnikov Research Institute of Cardiology, Russian Cardiology Scientific and Clinical Complex
| | | | - G. V. Mikhailova
- A.L. Myasnikov Research Institute of Cardiology, Russian Cardiology Scientific and Clinical Complex
| | - F. T. Ageev
- A.L. Myasnikov Research Institute of Cardiology, Russian Cardiology Scientific and Clinical Complex
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In pursuit of P2X3 antagonists: novel therapeutics for chronic pain and afferent sensitization. Purinergic Signal 2011; 8:3-26. [PMID: 22095157 PMCID: PMC3265711 DOI: 10.1007/s11302-011-9271-6] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Accepted: 09/19/2011] [Indexed: 12/20/2022] Open
Abstract
Treating pain by inhibiting ATP activation of P2X3-containing receptors heralds an exciting new approach to pain management, and Afferent's program marks the vanguard in a new class of drugs poised to explore this approach to meet the significant unmet needs in pain management. P2X3 receptor subunits are expressed predominately and selectively in so-called C- and Aδ-fiber primary afferent neurons in most tissues and organ systems, including skin, joints, and hollow organs, suggesting a high degree of specificity to the pain sensing system in the human body. P2X3 antagonists block the activation of these fibers by ATP and stand to offer an alternative approach to the management of pain and discomfort. In addition, P2X3 is expressed pre-synaptically at central terminals of C-fiber afferent neurons, where ATP further sensitizes transmission of painful signals. As a result of the selectivity of the expression of P2X3, there is a lower likelihood of adverse effects in the brain, gastrointestinal, or cardiovascular tissues, effects which remain limiting factors for many existing pain therapeutics. In the periphery, ATP (the factor that triggers P2X3 receptor activation) can be released from various cells as a result of tissue inflammation, injury or stress, as well as visceral organ distension, and stimulate these local nociceptors. The P2X3 receptor rationale has aroused a formidable level of investigation producing many reports that clarify the potential role of ATP as a pain mediator, in chronic sensitized states in particular, and has piqued the interest of pharmaceutical companies. P2X receptor-mediated afferent activation has been implicated in inflammatory, visceral, and neuropathic pain states, as well as in airways hyperreactivity, migraine, itch, and cancer pain. It is well appreciated that oftentimes new mechanisms translate poorly from models into clinical efficacy and effectiveness; however, the breadth of activity seen from P2X3 inhibition in models offers a realistic chance that this novel mechanism to inhibit afferent nerve sensitization may find its place in the sun and bring some merciful relief to the torment of persistent discomfort and pain. The development philosophy at Afferent is to conduct proof of concept patient studies and best identify target patient groups that may benefit from this new intervention.
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Lujan HL, Krishnan S, Dicarlo SE. Cardiac spinal deafferentation reduces the susceptibility to sustained ventricular tachycardia in conscious rats. Am J Physiol Regul Integr Comp Physiol 2011; 301:R775-82. [PMID: 21677267 PMCID: PMC3174758 DOI: 10.1152/ajpregu.00140.2011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 06/10/2011] [Indexed: 11/22/2022]
Abstract
The response to myocardial ischemia is complex and involves the cardio-cardiac sympathetic reflex. Specifically, cardiac spinal (sympathetic) afferents are excited by ischemic metabolites and elicit an excitatory sympathetic reflex, which plays a major role in the genesis of ventricular arrhythmias. For example, brief myocardial ischemia leads to ATP release, which activates cardiac spinal afferents through stimulation of P2 receptors. Clinical work with patients and preclinical work with animals document that disruption of this reflex protects against ischemia-induced ventricular arrhythmias. However, the role of afferent signals in the initiation of sustained ventricular tachycardia has not been investigated. Therefore, we tested the hypothesis that cardiac spinal deafferentation reduces the susceptibility to sustained ventricular tachycardia in adult (12-15 wk of age), conscious, male Sprague-Dawley rats. To test this hypothesis, the susceptibility to ventricular tachyarrhythmias produced by occlusion of the left main coronary artery was determined in two groups of conscious rats: 1) deafferentation (bilateral excision of the T1-T5 dorsal root ganglia) and 2) control (sham deafferentation). The ventricular arrhythmia threshold (VAT) was defined as the time from coronary occlusion to sustained ventricular tachycardia resulting in a reduction in arterial pressure. Results document a significantly higher VAT in the deafferentation group (7.0 ± 0.7 min) relative to control (4.3 ± 0.3 min) rats. The decreased susceptibility to tachyarrhythmias with deafferentation was associated with a reduced cardiac metabolic demand (lower rate-pressure product and ST segment elevation) during ischemia.
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Affiliation(s)
- Heidi L Lujan
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, USA
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Lujan HL, Palani G, DiCarlo SE. Structural neuroplasticity following T5 spinal cord transection: increased cardiac sympathetic innervation density and SPN arborization. Am J Physiol Regul Integr Comp Physiol 2010; 299:R985-95. [PMID: 20668234 DOI: 10.1152/ajpregu.00329.2010] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
When the spinal cord is injured at or below thoracic level 5 (T5), cardiovascular control is markedly unbalanced as the heart and blood vessels innervated by upper thoracic segments remain under brain stem control, whereas the vasculature of the lower body is affected by unregulated spinal reflexes. Importantly, the regulation of heart rate and cardiac function is abnormal after spinal cord injury (SCI) at T5 because sympathetic outflow to the heart is increased. An increase in tonic sympathetic outflow may be attributable to multiple mechanisms, such as increases in cardiac sympathetic innervation density, altered morphology of stellate ganglia neurons, and/or structural neuroplasticity of cardiac sympathetic preganglionic neurons (SPNs). Furthermore, these neuroplastic changes associated with SCI may be mediated by nerve growth factor (NGF). NGF is a neurotrophin that supports the survival and differentiation of sympathetic neurons and enhances target innervation. Therefore, we tested the hypothesis that T5 spinal cord transection (T5X) is associated with an increased left ventricular (LV) NGF content, LV sympathetic innervation density, and cardiac SPN arborization. In intact and paraplegic (9 wk posttransection) rats, LV NGF content (ELISA), LV sympathetic innervation density (tyrosine hydroxylase immunohistochemistry), and cardiac SPN arborization (cholera toxin B immunohistochemistry and Sholl Analysis) were determined. Paraplegia, compared with intact, significantly increased LV NGF content, LV sympathetic innervation density, and cardiac SPN arborization. Thus, altered autonomic behavior following SCI is associated with structural neuroplastic modifications.
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Affiliation(s)
- Heidi L Lujan
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
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