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Zhang H, Wang Y, Wu Y, Luo Z, Zhong M, Hong Z, Wang D. Intrathecal Anesthesia Prevents Ventricular Arrhythmias in Rats with Myocardial Ischemia/Reperfusion. Pharmacology 2024; 109:253-265. [PMID: 38648737 DOI: 10.1159/000538997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 04/05/2024] [Indexed: 04/25/2024]
Abstract
INTRODUCTION Ventricular arrhythmia is commonly provoked by acute cardiac ischemia through sympathetic exaggeration and is often resistant to anti-arrhythmic therapies. Thoracic epidural anesthesia has been reported to terminate fatal ventricular arrhythmia; however, its underlying mechanism is unknown. METHODS Rats were randomly divided into four groups: sham, sham plus bupivacaine, ischemia/reperfusion (IR), and IR plus bupivacaine groups. Bupivacaine (1 mg/mL, 0.05 mL/100 g body weight) was injected intrathecally into the L5-L6 intervertebral space prior to establishing a myocardial IR rat model. Thereafter, cardiac arrhythmia, cardiac function, myocardial injury, and electrical activities of the heart and spinal cord were evaluated. RESULTS Intrathecal bupivacaine inhibited spinal neural activity, improved heart rate variability, reduced ventricular arrhythmia score, and ameliorated cardiac dysfunction in IR rats. Furthermore, intrathecal bupivacaine attenuated cardiac injury and myocardial apoptosis and regulated cardiomyocyte autophagy and connexin-43 distribution during myocardial IR. CONCLUSION Our results indicate that intrathecal bupivacaine blunts spinal neural activity to prevent cardiac arrhythmia and dysfunction induced by IR and that this anti-arrhythmic activity may be associated with regulation of autonomic balance, myocardial apoptosis and autophagy, and cardiac gap junction function.
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MESH Headings
- Animals
- Bupivacaine/administration & dosage
- Myocardial Reperfusion Injury/prevention & control
- Male
- Rats, Sprague-Dawley
- Arrhythmias, Cardiac/prevention & control
- Arrhythmias, Cardiac/etiology
- Rats
- Injections, Spinal
- Anesthetics, Local/pharmacology
- Anesthetics, Local/administration & dosage
- Anesthesia, Spinal
- Connexin 43/metabolism
- Apoptosis/drug effects
- Heart Rate/drug effects
- Autophagy/drug effects
- Myocytes, Cardiac/drug effects
- Myocytes, Cardiac/metabolism
- Anti-Arrhythmia Agents/administration & dosage
- Anti-Arrhythmia Agents/pharmacology
- Disease Models, Animal
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Affiliation(s)
- Huabin Zhang
- Department of Gerontology, The First Affiliated Hospital of Wannan Medical College, Yijishan Hospital, Wuhu, China
| | - Yue Wang
- Department of Gerontology, The First Affiliated Hospital of Wannan Medical College, Yijishan Hospital, Wuhu, China
| | - Yong Wu
- Department of Gerontology, The First Affiliated Hospital of Wannan Medical College, Yijishan Hospital, Wuhu, China
- Department of Geriatrics, The Affiliated Taizhou People's Hospital of Nanjing Medical University, Taizhou, China
| | - Zhongxu Luo
- Department of Gerontology, The First Affiliated Hospital of Wannan Medical College, Yijishan Hospital, Wuhu, China
| | - Ming Zhong
- Key Laboratory of Non-coding RNA Transformation Research of Anhui Higher Education Institution, Wannan Medical College, Wuhu, China
| | - Zongyuan Hong
- School of Pharmacy, Wannan Medical College, Wuhu, China
| | - Deguo Wang
- Department of Gerontology, The First Affiliated Hospital of Wannan Medical College, Yijishan Hospital, Wuhu, China
- Key Laboratory of Non-coding RNA Transformation Research of Anhui Higher Education Institution, Wannan Medical College, Wuhu, China
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Salavatian S, Robbins EM, Kuwabara Y, Castagnola E, Cui XT, Mahajan A. Real-time in vivo thoracic spinal glutamate sensing during myocardial ischemia. Am J Physiol Heart Circ Physiol 2023; 325:H1304-H1317. [PMID: 37737733 PMCID: PMC10908408 DOI: 10.1152/ajpheart.00299.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 09/18/2023] [Accepted: 09/18/2023] [Indexed: 09/23/2023]
Abstract
In the spinal cord, glutamate serves as the primary excitatory neurotransmitter. Monitoring spinal glutamate concentrations offers valuable insights into spinal neural processing. Consequently, spinal glutamate concentration has the potential to emerge as a useful biomarker for conditions characterized by increased spinal neural network activity, especially when uptake systems become dysfunctional. In this study, we developed a multichannel custom-made flexible glutamate-sensing probe for the large-animal model that is capable of measuring extracellular glutamate concentrations in real time and in vivo. We assessed the probe's sensitivity and specificity through in vitro and ex vivo experiments. Remarkably, this developed probe demonstrates nearly instantaneous glutamate detection and allows continuous monitoring of glutamate concentrations. Furthermore, we evaluated the mechanical and sensing performance of the probe in vivo, within the pig spinal cord. Moreover, we applied the glutamate-sensing method using the flexible probe in the context of myocardial ischemia-reperfusion (I/R) injury. During I/R injury, cardiac sensory neurons in the dorsal root ganglion transmit excitatory signals to the spinal cord, resulting in sympathetic activation that potentially leads to fatal arrhythmias. We have successfully shown that our developed glutamate-sensing method can detect this spinal network excitation during myocardial ischemia. This study illustrates a novel technique for measuring spinal glutamate at different spinal cord levels as a surrogate for the spinal neural network activity during cardiac interventions that engage the cardio-spinal neural pathway.NEW & NOTEWORTHY In this study, we have developed a new flexible sensing probe to perform an in vivo measurement of spinal glutamate signaling in a large animal model. Our initial investigations involved precise testing of this probe in both in vitro and ex vivo environments. We accurately assessed the sensitivity and specificity of our glutamate-sensing probe and demonstrated its performance. We also evaluated the performance of our developed flexible probe during the insertion and compared it with the stiff probe during animal movement. Subsequently, we used this innovative technique to monitor the spinal glutamate signaling during myocardial ischemia and reperfusion that can cause fatal ventricular arrhythmias. We showed that glutamate concentration increases during the myocardial ischemia, persists during the reperfusion, and is associated with sympathoexcitation and increases in myocardial substrate excitability.
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Affiliation(s)
- Siamak Salavatian
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Division of Cardiology, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Elaine Marie Robbins
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Yuki Kuwabara
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Elisa Castagnola
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Xinyan Tracy Cui
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Center for Neural Basis of Cognition, Pittsburgh, Pennsylvania, United States
- McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania, United States
| | - Aman Mahajan
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
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Salavatian S, Kuwabara Y, Wong B, Fritz JR, Howard-Quijano K, Foreman RD, Armour JA, Ardell JL, Mahajan A. Spinal neuromodulation mitigates myocardial ischemia-induced sympathoexcitation by suppressing the intermediolateral nucleus hyperactivity and spinal neural synchrony. Front Neurosci 2023; 17:1180294. [PMID: 37332861 PMCID: PMC10272539 DOI: 10.3389/fnins.2023.1180294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 05/16/2023] [Indexed: 06/20/2023] Open
Abstract
Introduction Myocardial ischemia disrupts the cardio-spinal neural network that controls the cardiac sympathetic preganglionic neurons, leading to sympathoexcitation and ventricular tachyarrhythmias (VTs). Spinal cord stimulation (SCS) is capable of suppressing the sympathoexcitation caused by myocardial ischemia. However, how SCS modulates the spinal neural network is not fully known. Methods In this pre-clinical study, we investigated the impact of SCS on the spinal neural network in mitigating myocardial ischemia-induced sympathoexcitation and arrhythmogenicity. Ten Yorkshire pigs with left circumflex coronary artery (LCX) occlusion-induced chronic myocardial infarction (MI) were anesthetized and underwent laminectomy and a sternotomy at 4-5 weeks post-MI. The activation recovery interval (ARI) and dispersion of repolarization (DOR) were analyzed to evaluate the extent of sympathoexcitation and arrhythmogenicity during the left anterior descending coronary artery (LAD) ischemia. Extracellular in vivo and in situ spinal dorsal horn (DH) and intermediolateral column (IML) neural recordings were performed using a multichannel microelectrode array inserted at the T2-T3 segment of the spinal cord. SCS was performed for 30 min at 1 kHz, 0.03 ms, 90% motor threshold. LAD ischemia was induced pre- and 1 min post-SCS to investigate how SCS modulates spinal neural network processing of myocardial ischemia. DH and IML neural interactions, including neuronal synchrony as well as cardiac sympathoexcitation and arrhythmogenicity markers were evaluated during myocardial ischemia pre- vs. post-SCS. Results ARI shortening in the ischemic region and global DOR augmentation due to LAD ischemia was mitigated by SCS. Neural firing response of ischemia-sensitive neurons during LAD ischemia and reperfusion was blunted by SCS. Further, SCS showed a similar effect in suppressing the firing response of IML and DH neurons during LAD ischemia. SCS exhibited a similar suppressive impact on the mechanical, nociceptive and multimodal ischemia sensitive neurons. The LAD ischemia and reperfusion-induced augmentation in neuronal synchrony between DH-DH and DH-IML pairs of neurons were mitigated by the SCS. Discussion These results suggest that SCS is decreasing the sympathoexcitation and arrhythmogenicity by suppressing the interactions between the spinal DH and IML neurons and activity of IML preganglionic sympathetic neurons.
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Affiliation(s)
- Siamak Salavatian
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
- Division of Cardiology, Department of Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Yuki Kuwabara
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Benjamin Wong
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Jonathan R. Fritz
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Kimberly Howard-Quijano
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Robert D. Foreman
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - J. Andrew Armour
- Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States
| | - Jeffrey L. Ardell
- Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States
| | - Aman Mahajan
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
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Howard-Quijano K, Kuwabara Y, Yamaguchi T, Roman K, Salavatian S, Taylor B, Mahajan A. GABAergic Signaling during Spinal Cord Stimulation Reduces Cardiac Arrhythmias in a Porcine Model. Anesthesiology 2023; 138:372-387. [PMID: 36724342 PMCID: PMC9998372 DOI: 10.1097/aln.0000000000004516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Neuraxial modulation, including spinal cord stimulation, reduces cardiac sympathoexcitation and ventricular arrhythmogenesis. There is an incomplete understanding of the molecular mechanisms through which spinal cord stimulation modulates cardiospinal neural pathways. The authors hypothesize that spinal cord stimulation reduces myocardial ischemia-reperfusion-induced sympathetic excitation and ventricular arrhythmias through γ-aminobutyric acid (GABA)-mediated pathways in the thoracic spinal cord. METHODS Yorkshire pigs were randomized to control (n = 11), ischemia-reperfusion (n = 16), ischemia-reperfusion plus spinal cord stimulation (n = 17), ischemia-reperfusion plus spinal cord stimulation plus γ-aminobutyric acid type A (GABAA) or γ-aminobutyric acid type B (GABAB) receptor antagonist (GABAA, n = 8; GABAB, n = 8), and ischemia-reperfusion plus GABA transaminase inhibitor (GABAculine, n = 8). A four-pole spinal cord stimulation lead was placed epidurally (T1 to T4). GABA modulating pharmacologic agents were administered intrathecally. Spinal cord stimulation at 50 Hz was applied 30 min before ischemia. A 56-electrode epicardial mesh was used for high-resolution electrophysiologic recordings, including activation recovery intervals and ventricular arrhythmia scores. Immunohistochemistry and Western blots were performed to measure GABA receptor expression in the thoracic spinal cord. RESULTS Cardiac ischemia led to myocardial sympathoexcitation with reduction in activation recovery interval (mean ± SD, -42 ± 11%), which was attenuated by spinal cord stimulation (-21 ± 17%, P = 0.001). GABAA and GABAB receptor antagonists abolished spinal cord stimulation attenuation of sympathoexcitation (GABAA, -9.7 ± 9.7%, P = 0.043 vs. ischemia-reperfusion plus spinal cord stimulation; GABAB, -13 ± 14%, P = 0.012 vs. ischemia-reperfusion plus spinal cord stimulation), while GABAculine alone caused a therapeutic effect similar to spinal cord stimulation (-4.1 ± 3.7%, P = 0.038 vs. ischemia-reperfusion). The ventricular arrhythmia score supported these findings. Spinal cord stimulation during ischemia-reperfusion increased GABAA receptor expression with no change in GABAB receptor expression. CONCLUSIONS Thoracic spinal cord stimulation reduces ischemia-reperfusion-induced sympathoexcitation and ventricular arrhythmias through activation of GABA signaling pathways. These data support the hypothesis that spinal cord stimulation-induced release of GABA activates inhibitory interneurons to decrease primary afferent signaling from superficial dorsal horn to sympathetic output neurons in the intermediolateral nucleus. EDITOR’S PERSPECTIVE
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Affiliation(s)
- Kimberly Howard-Quijano
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh. A-1305 Scaife Hall, 3550 Terrace Street Pittsburgh, PA 15261, United States
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh Medical Center. 200 Lothrop St, Pittsburgh, PA 15213, United States
| | - Yuki Kuwabara
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh. A-1305 Scaife Hall, 3550 Terrace Street Pittsburgh, PA 15261, United States
| | - Tomoki Yamaguchi
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh. A-1305 Scaife Hall, 3550 Terrace Street Pittsburgh, PA 15261, United States
| | - Kenny Roman
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh. A-1305 Scaife Hall, 3550 Terrace Street Pittsburgh, PA 15261, United States
| | - Siamak Salavatian
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh. A-1305 Scaife Hall, 3550 Terrace Street Pittsburgh, PA 15261, United States
| | - Bradley Taylor
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh. A-1305 Scaife Hall, 3550 Terrace Street Pittsburgh, PA 15261, United States
| | - Aman Mahajan
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh. A-1305 Scaife Hall, 3550 Terrace Street Pittsburgh, PA 15261, United States
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh Medical Center. 200 Lothrop St, Pittsburgh, PA 15213, United States
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Salavatian S, Robbins EM, Kuwabara Y, Castagnola E, Cui XT, Mahajan A. Real-time in vivo thoracic spinal glutamate sensing reveals spinal hyperactivity during myocardial ischemia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.11.531911. [PMID: 36993301 PMCID: PMC10054946 DOI: 10.1101/2023.03.11.531911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Myocardial ischemia-reperfusion (IR) can cause ventricular arrhythmias and sudden cardiac death via sympathoexcitation. The spinal cord neural network is crucial in triggering these arrhythmias and evaluating its neurotransmitter activity during IR is critical for understanding ventricular excitability control. To assess the real-time in vivo spinal neural activity in a large animal model, we developed a flexible glutamate-sensing multielectrode array. To record the glutamate signaling during IR injury, we inserted the probe into the dorsal horn of the thoracic spinal cord at the T2-T3 where neural signals generated by the cardiac sensory neurons are processed and provide sympathoexcitatory feedback to the heart. Using the glutamate sensing probe, we found that the spinal neural network was excited during IR, especially after 15 mins, and remained elevated during reperfusion. Higher glutamate signaling was correlated with the reduction in the cardiac myocyte activation recovery interval, showing higher sympathoexcitation, as well as dispersion of the repolarization which is a marker for increased risk of arrhythmias. This study illustrates a new technique for measuring the spinal glutamate at different spinal cord levels as a surrogate for the spinal neural network activity during cardiac interventions that engage the cardio-spinal neural pathway. Graphical abstract
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Kuwabara Y, Howard-Quijano K, Salavatian S, Yamaguchi T, Saba S, Mahajan A. Thoracic dorsal root ganglion stimulation reduces acute myocardial ischemia induced ventricular arrhythmias. Front Neurosci 2023; 17:1091230. [PMID: 36793544 PMCID: PMC9922704 DOI: 10.3389/fnins.2023.1091230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Accepted: 01/09/2023] [Indexed: 02/03/2023] Open
Abstract
Background Dorsal root ganglion stimulation (DRGS) may serve as a novel neuromodulation strategy to reduce cardiac sympathoexcitation and ventricular excitability. Objective In this pre-clinical study, we investigated the effectiveness of DRGS on reducing ventricular arrhythmias and modulating cardiac sympathetic hyperactivity caused by myocardial ischemia. Methods Twenty-three Yorkshire pigs were randomized to two groups, which was control LAD ischemia-reperfusion (CONTROL) or LAD ischemia-reperfusion + DRGS (DRGS) group. In the DRGS group (n = 10), high-frequency stimulation (1 kHz) at the second thoracic level (T2) was initiated 30 min before ischemia and continued throughout 1 h of ischemia and 2 h of reperfusion. Cardiac electrophysiological mapping and Ventricular Arrhythmia Score (VAS) were assessed, along with evaluation of cFos expression and apoptosis in the T2 spinal cord and DRG. Results DRGS decreased the magnitude of activation recovery interval (ARI) shortening in the ischemic region (CONTROL: -201 ± 9.8 ms, DRGS: -170 ± 9.4 ms, p = 0.0373) and decreased global dispersion of repolarization (DOR) at 30 min of myocardial ischemia (CONTROL: 9546 ± 763 ms2, DRGS: 6491 ± 636 ms2, p = 0.0076). DRGS also decreased ventricular arrhythmias (VAS-CONTROL: 8.9 ± 1.1, DRGS: 6.3 ± 1.0, p = 0.038). Immunohistochemistry studies showed that DRGS decreased % cFos with NeuN expression in the T2 spinal cord (p = 0.048) and the number of apoptotic cells in the DRG (p = 0.0084). Conclusion DRGS reduced the burden of myocardial ischemia-induced cardiac sympathoexcitation and has a potential to be a novel treatment option to reduce arrhythmogenesis.
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Affiliation(s)
- Yuki Kuwabara
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Kimberly Howard-Quijano
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Siamak Salavatian
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
- Division of Cardiology, Department of Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Tomoki Yamaguchi
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Samir Saba
- Division of Cardiology, Department of Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Aman Mahajan
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
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Li J, Tang H, Tu W. Mechanism of dexmedetomidine preconditioning on spinal cord analgesia in rats with functional chronic visceral pain. Acta Cir Bras 2022; 37:e370203. [PMID: 35507967 PMCID: PMC9064187 DOI: 10.1590/acb370203] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 01/03/2022] [Indexed: 11/22/2022] Open
Abstract
Purpose: To analyze the effect and mechanism of dexmedetomidine (DEX) analgesia pretreatment on functional chronic visceral pain in rats. Methods: Rats were divided into six groups: W1, W2, W3, W4, W5, and W6. The behavioral changes and electrophysiological indexes of rats in each group before and after DEX treatment were detected. Results: The levels of abdominal withdrawal reflex (AWR) in W5 and W6 groups were significantly lower than those in group W3, while the levels of thermal withdrawal latency (TWL) and mechanical withdrawal threshold (MWT) were significantly higher than those in group W3 (p < 0.05). The electromyographic signals of W1, W5, and W6 groups showed little fluctuation, while those of groups W2, W3, and W4 showed obvious fluctuation. TLR4 mRNA expression, IRF3, P65, and phosphorylation levels in W4, W5, and W6 groups were significantly lower than those in group W2 (p < 0.05). Conclusions: Dexmedetomidine epidural anesthesia pretreatment could significantly inhibit visceral pain response in rats with functional chronic visceral pain, and its mechanism was related to the activation of TLR4 in spinal dorsal horn tissue of rats and the activation inhibition of IRF3 and P65 in the downstream key signals.
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Affiliation(s)
- Jun Li
- Southern Medical University, China
| | - Huizhong Tang
- People’s Hospital of Guangxi Zhuang Autonomous Region, China
| | - Weifeng Tu
- General Hospital of Southern Theatre Command, China
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Gurel NZ, Sudarshan KB, Tam S, Ly D, Armour JA, Kember G, Ajijola OA. Studying Cardiac Neural Network Dynamics: Challenges and Opportunities for Scientific Computing. Front Physiol 2022; 13:835761. [PMID: 35574437 PMCID: PMC9099376 DOI: 10.3389/fphys.2022.835761] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 04/06/2022] [Indexed: 11/13/2022] Open
Abstract
Neural control of the heart involves continuous modulation of cardiac mechanical and electrical activity to meet the organism's demand for blood flow. The closed-loop control scheme consists of interconnected neural networks with central and peripheral components working cooperatively with each other. These components have evolved to cooperate control of various aspects of cardiac function, which produce measurable "functional" outputs such as heart rate and blood pressure. In this review, we will outline fundamental studies probing the cardiac neural control hierarchy. We will discuss how computational methods can guide improved experimental design and be used to probe how information is processed while closed-loop control is operational. These experimental designs generate large cardio-neural datasets that require sophisticated strategies for signal processing and time series analysis, while presenting the usual large-scale computational challenges surrounding data sharing and reproducibility. These challenges provide unique opportunities for the development and validation of novel techniques to enhance understanding of mechanisms of cardiac pathologies required for clinical implementation.
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Affiliation(s)
- Nil Z. Gurel
- UCLA Neurocardiology Research Program of Excellence, Los Angeles, CA, United States
- UCLA Cardiac Arrhythmia Center, UCLA Health System, Los Angeles, CA, United States
| | - Koustubh B. Sudarshan
- Department of Engineering Mathematics and Internetworking, Dalhousie University, Halifax, NS, Canada
| | - Sharon Tam
- UCLA Department of Bioengineering, Los Angeles, CA, United States
| | - Diana Ly
- UCLA Department of Bioengineering, Los Angeles, CA, United States
| | - J. Andrew Armour
- UCLA Neurocardiology Research Program of Excellence, Los Angeles, CA, United States
- UCLA Cardiac Arrhythmia Center, UCLA Health System, Los Angeles, CA, United States
| | - Guy Kember
- Department of Engineering Mathematics and Internetworking, Dalhousie University, Halifax, NS, Canada
| | - Olujimi A. Ajijola
- UCLA Neurocardiology Research Program of Excellence, Los Angeles, CA, United States
- UCLA Cardiac Arrhythmia Center, UCLA Health System, Los Angeles, CA, United States
- Molecular, Cellular and Integrative Physiology Program, UCLA, Los Angeles, CA, United States
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Kuwabara Y, Salavatian S, Howard-Quijano K, Yamaguchi T, Lundquist E, Mahajan A. Neuromodulation With Thoracic Dorsal Root Ganglion Stimulation Reduces Ventricular Arrhythmogenicity. Front Physiol 2021; 12:713717. [PMID: 34690795 PMCID: PMC8528951 DOI: 10.3389/fphys.2021.713717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 08/31/2021] [Indexed: 11/13/2022] Open
Abstract
Introduction: Sympathetic hyperactivity is strongly associated with ventricular arrhythmias and sudden cardiac death. Neuromodulation provides therapeutic options for ventricular arrhythmias by modulating cardiospinal reflexes and reducing sympathetic output at the level of the spinal cord. Dorsal root ganglion stimulation (DRGS) is a recent neuromodulatory approach; however, its role in reducing ventricular arrhythmias has not been evaluated. The aim of this study was to determine if DRGS can reduce cardiac sympathoexcitation and the indices for ventricular arrhythmogenicity induced by programmed ventricular extrastimulation. We evaluated the efficacy of thoracic DRGS at both low (20 Hz) and high (1 kHz) stimulation frequencies. Methods: Cardiac sympathoexcitation was induced in Yorkshire pigs (n = 8) with ventricular extrastimulation (S1/S2 pacing), before and after DRGS. A DRG-stimulating catheter was placed at the left T2 spinal level, and animals were randomized to receive low-frequency (20 Hz and 0.4 ms) or high-frequency (1 kHz and 0.03 ms) DRGS for 30 min. High-fidelity cardiac electrophysiological recordings were performed with an epicardial electrode array measuring the indices of ventricular arrhythmogenicity-activation recovery intervals (ARIs), electrical restitution curve (Smax), and Tpeak-Tend interval (Tp-Te interval). Results: Dorsal root ganglion stimulation, at both 20 Hz and 1 kHz, decreased S1/S2 pacing-induced ARI shortening (20 Hz DRGS -21±7 ms, Control -50±9 ms, P = 0.007; 1 kHz DRGS -13 ± 2 ms, Control -46 ± 8 ms, P = 0.001). DRGS also reduced arrhythmogenicity as measured by a decrease in Smax (20 Hz DRGS 0.5 ± 0.07, Control 0.7 ± 0.04, P = 0.006; 1 kHz DRGS 0.5 ± 0.04, Control 0.7 ± 0.03, P = 0.007), and a decrease in Tp-Te interval/QTc (20 Hz DRGS 2.7 ± 0.13, Control 3.3 ± 0.12, P = 0.001; 1 kHz DRGS 2.8 ± 0.08, Control; 3.1 ± 0.03, P = 0.007). Conclusions: In a porcine model, we show that thoracic DRGS decreased cardiac sympathoexcitation and indices associated with ventricular arrhythmogenicity during programmed ventricular extrastimulation. In addition, we demonstrate that both low-frequency and high-frequency DRGS can be effective neuromodulatory approaches for reducing cardiac excitability during sympathetic hyperactivity.
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Affiliation(s)
- Yuki Kuwabara
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Siamak Salavatian
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Kimberly Howard-Quijano
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Tomoki Yamaguchi
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Eevanna Lundquist
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Aman Mahajan
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
- Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
- *Correspondence: Aman Mahajan
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