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Abstract
Neuropathic pain is a debilitating form of pain arising from injury or disease of the nervous system that affects millions of people worldwide. Despite its prevalence, the underlying mechanisms of neuropathic pain are still not fully understood. Dendritic spines are small protrusions on the surface of neurons that play an important role in synaptic transmission. Recent studies have shown that dendritic spines reorganize in the superficial and deeper laminae of the spinal cord dorsal horn with the development of neuropathic pain in multiple models of disease or injury. Given the importance of dendritic spines in synaptic transmission, it is possible that studying dendritic spines could lead to new therapeutic approaches for managing intractable pain. In this review article, we highlight the emergent role of dendritic spines in neuropathic pain, as well as discuss the potential for studying dendritic spines for the development of new therapeutics.
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Affiliation(s)
- Curtis A Benson
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
| | - Jared F King
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
| | - Marike L Reimer
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
| | - Sierra D Kauer
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
| | - Stephen G Waxman
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
| | - Andrew M Tan
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
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Cui X, Liu J, Uniyal A, Xu Q, Zhang C, Zhu G, Yang F, Sivanesan E, Linderoth B, Raja SN, Guan Y. Enhancing spinal cord stimulation-induced pain inhibition by augmenting endogenous adenosine signalling after nerve injury in rats. Br J Anaesth 2024; 132:746-757. [PMID: 38310069 PMCID: PMC10925891 DOI: 10.1016/j.bja.2024.01.005] [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: 11/28/2023] [Revised: 01/03/2024] [Accepted: 01/05/2024] [Indexed: 02/05/2024] Open
Abstract
BACKGROUND The mechanisms for spinal cord stimulation (SCS) to alleviate chronic pain are only partially known. We aimed to elucidate the roles of adenosine A1 and A3 receptors (A1R, A3R) in the inhibition of spinal nociceptive transmission by SCS, and further explored whether 2'-deoxycoformycin (dCF), an inhibitor of adenosine deaminase, can potentiate SCS-induced analgesia. METHODS We used RNAscope and immunoblotting to examine the distributions of adora1 and adora3 expression, and levels of A1R and A3R proteins in the spinal cord of rats after tibial-spared nerve injury (SNI-t). Electrophysiology recording was conducted to examine how adenosine receptor antagonists, virus-mediated adora3 knockdown, and dCF affect SCS-induced inhibition of C-fibre-evoked spinal local field potential (C-LFP). RESULTS Adora1 was predominantly expressed in neurones, whereas adora3 is highly expressed in microglial cells in the rat spinal cord. Spinal application of antagonists (100 μl) of A1R (8-cyclopentyl-1,3-dipropylxanthine [DPCPX], 50 μM) and A3R (MRS1523, 200 nM) augmented C-LFP in SNI-t rats (DPCPX: 1.39 [0.18] vs vehicle: 0.98 [0.05], P=0.046; MRS1523: 1.21 [0.07] vs vehicle: 0.91 [0.03], P=0.002). Both drugs also blocked inhibition of C-LFP by SCS. Conversely, dCF (0.1 mM) enhanced SCS-induced C-LFP inhibition (dCF: 0.60 [0.04] vs vehicle: 0.85 [0.02], P<0.001). In the behaviour study, dCF (100 nmol 15 μl-1, intrathecal) also enhanced inhibition of mechanical hypersensitivity by SCS in SNI-t rats. CONCLUSIONS Spinal A1R and A3R signalling can exert tonic suppression and also contribute to SCS-induced inhibition of spinal nociceptive transmission after nerve injury. Inhibition of adenosine deaminase may represent a novel adjuvant pharmacotherapy to enhance SCS-induced analgesia.
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Affiliation(s)
- Xiang Cui
- Department of Anaesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Jing Liu
- Department of Anaesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Ankit Uniyal
- Department of Anaesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Qian Xu
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University, School of Medicine, Baltimore, MD, USA; Howard Hughes Medical Institute, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Chi Zhang
- Department of Anaesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Guangwu Zhu
- Department of Anaesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Fei Yang
- Department of Anaesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Eellan Sivanesan
- Department of Anaesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Bengt Linderoth
- Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden
| | - Srinivasa N Raja
- Department of Anaesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Yun Guan
- Department of Anaesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA; Department of Neurological Surgery, Johns Hopkins University, School of Medicine, Baltimore, MD, USA.
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Zhang H, Rodriguez-Hernandez LD, D'Souza AJ, He D, Zain M, Fung SW, Bennett LA, Bonin RP. Nociceptor activity induces nonionotropic NMDA receptor signaling to enable spinal reconsolidation and reverse pathological pain. SCIENCE ADVANCES 2023; 9:eadg2819. [PMID: 37205760 DOI: 10.1126/sciadv.adg2819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 04/17/2023] [Indexed: 05/21/2023]
Abstract
Chronic, pathological pain is a highly debilitating condition that can arise and be maintained through central sensitization. Central sensitization shares mechanistic and phenotypic parallels with memory formation. In a sensory model of memory reconsolidation, plastic changes underlying pain hypersensitivity can be dynamically regulated and reversed following the reactivation of sensitized sensory pathways. However, the mechanisms by which synaptic reactivation induces destabilization of the spinal "pain engram" are unclear. We identified nonionotropic N-methyl-d-aspartate receptor (NI-NMDAR) signaling as necessary and sufficient for the reactive destabilization of dorsal horn long-term potentiation and the reversal of mechanical sensitization associated with central sensitization. NI-NMDAR signaling engaged directly or through the reactivation of sensitized sensory networks was associated with the degradation of excitatory postsynaptic proteins. Our findings identify NI-NMDAR signaling as a putative synaptic mechanism by which engrams are destabilized in reconsolidation and as a potential means of treating underlying causes of chronic pain.
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Affiliation(s)
- Hantao Zhang
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Luis D Rodriguez-Hernandez
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Abigail J D'Souza
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - David He
- Department of Anesthesia, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Maham Zain
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Samuel W Fung
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Laura A Bennett
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Robert P Bonin
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
- University of Toronto Centre for the Study of Pain, University of Toronto, Toronto, Ontario, Canada
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Sampaio-Cunha TJ, Martins I. Knowing the Enemy Is Halfway towards Victory: A Scoping Review on Opioid-Induced Hyperalgesia. J Clin Med 2022; 11:jcm11206161. [PMID: 36294488 PMCID: PMC9604911 DOI: 10.3390/jcm11206161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 10/14/2022] [Accepted: 10/17/2022] [Indexed: 11/26/2022] Open
Abstract
Opioid-induced hyperalgesia (OIH) is a paradoxical effect of opioids that is not consensually recognized in clinical settings. We conducted a revision of clinical and preclinical studies and discuss them side by side to provide an updated and renewed view on OIH. We critically analyze data on the human manifestations of OIH in the context of chronic and post-operative pain. We also discuss how, in the context of cancer pain, though there are no direct evidence of OIH, several inherent conditions to the tumor and chemotherapy provide a substrate for the development of OIH. The review of the clinical data, namely in what concerns the strategies to counter OIH, emphasizes how much OIH rely mechanistically on the existence of µ-opioid receptor (MOR) signaling through opposite, inhibitory/antinociceptive and excitatory/pronociceptive, pathways. The rationale for the maladaptive excitatory signaling of opioids is provided by the emerging growing information on the functional role of alternative splicing and heteromerization of MOR. The crossroads between opioids and neuroinflammation also play a major role in OIH. The latest pre-clinical data in this field brings new insights to new and promising therapeutic targets to address OIH. In conclusion, although OIH remains insufficiently recognized in clinical practice, the appropriate diagnosis can turn it into a treatable pain disorder. Therefore, in times of scarce alternatives to opioids to treat pain, mainly unmanageable chronic pain, increased knowledge and recognition of OIH, likely represent the first steps towards safer and efficient use of opioids as analgesics.
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Affiliation(s)
- Tiago J. Sampaio-Cunha
- Department of Biomedicine, Unit of Experimental Biology, Faculty of Medicine of the University of Porto, 4200-319 Porto, Portugal
- i3S–Institute for Research & Innovation in Health, University of Porto, 4200-135 Porto, Portugal
- IBMC-Institute for Molecular and Cell Biology, University of Porto, 4200-135 Porto, Portugal
| | - Isabel Martins
- Department of Biomedicine, Unit of Experimental Biology, Faculty of Medicine of the University of Porto, 4200-319 Porto, Portugal
- i3S–Institute for Research & Innovation in Health, University of Porto, 4200-135 Porto, Portugal
- IBMC-Institute for Molecular and Cell Biology, University of Porto, 4200-135 Porto, Portugal
- Correspondence: ; Tel.: +351-22-0426780; Fax: +351-22-5513655
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Chen M, Chen Z, Xiao X, Zhou L, Fu R, Jiang X, Pang M, Xia J. Corticospinal circuit neuroplasticity may involve silent synapses: Implications for functional recovery facilitated by neuromodulation after spinal cord injury. IBRO Neurosci Rep 2022; 14:185-194. [PMID: 36824667 PMCID: PMC9941655 DOI: 10.1016/j.ibneur.2022.08.005] [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: 06/07/2022] [Accepted: 08/15/2022] [Indexed: 10/15/2022] Open
Abstract
Spinal cord injury (SCI) leads to devastating physical consequences, such as severe sensorimotor dysfunction even lifetime disability, by damaging the corticospinal system. The conventional opinion that SCI is intractable due to the poor regeneration of neurons in the adult central nervous system (CNS) needs to be revisited as the CNS is capable of considerable plasticity, which underlie recovery from neural injury. Substantial spontaneous neuroplasticity has been demonstrated in the corticospinal motor circuitry following SCI. Some of these plastic changes appear to be beneficial while others are detrimental toward locomotor function recovery after SCI. The beneficial corticospinal plasticity in the spared corticospinal circuits can be harnessed therapeutically by multiple contemporary neuromodulatory approaches, especially the electrical stimulation-based modalities, in an activity-dependent manner to improve functional outcomes in post-SCI rehabilitation. Silent synapse generation and unsilencing contribute to profound neuroplasticity that is implicated in a variety of neurological disorders, thus they may be involved in the corticospinal motor circuit neuroplasticity following SCI. Exploring the underlying mechanisms of silent synapse-mediated neuroplasticity in the corticospinal motor circuitry that may be exploited by neuromodulation will inform a novel direction for optimizing therapeutic repair strategies and rehabilitative interventions in SCI patients.
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Key Words
- AMPARs, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors
- BDNF, brain-derived neurotrophic factor
- BMIs, brain-machine interfaces
- CPG, central pattern generator
- CST, corticospinal tract
- Corticospinal motor circuitry
- DBS, deep brain stimulation
- ESS, epidural spinal stimulation
- MEPs, motor-evoked potentials
- NHPs, non-human primates
- NMDARs, N-methyl-d-aspartate receptors
- Neuromodulation
- Neuroplasticity
- PSNs, propriospinal neurons
- Rehabilitation
- SCI, spinal cord injury
- STDP, spike timing-dependent plasticity
- Silent synapses
- Spinal cord injury
- TBS, theta burst stimulation
- TMS, transcranial magnetic stimulation
- TrkB, tropomyosin-related kinase B
- cTBS, continuous TBS
- iTBS, intermittent TBS
- mTOR, mammalian target of rapamycin
- rTMS, repetitive TMS
- tDCS, transcranial direct current stimulation
- tcSCS, transcutaneous spinal cord stimulation
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Affiliation(s)
- Mingcong Chen
- Department of Orthopedics and Traumatology, Shenzhen University General Hospital, Shenzhen, Guangdong 518055, China
| | - Zuxin Chen
- Shenzhen Key Laboratory of Drug Addiction, Shenzhen Neher Neural Plasticity Laboratory, the Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences (CAS); Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, Guangdong 518055, China
| | - Xiao Xiao
- Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence, Ministry of Education; Behavioral and Cognitive Neuroscience Center, Institute of Science and Technology for Brain-Inspired Intelligence; MOE Frontiers Center for Brain Science, Fudan University, Shanghai 200433, China
| | - Libing Zhou
- Guangdong-Hongkong-Macau CNS Regeneration Institute of Jinan University, Key Laboratory of CNS Regeneration (Jinan University)-Ministry of Education, Guangzhou, Guangdong 510632, China
| | - Rao Fu
- Department of Anatomy, School of Medicine, Sun Yat-sen University, Shenzhen, Guangdong 518100, China
| | - Xian Jiang
- Institute of Neurological and Psychiatric Disorder, Shenzhen Bay laboratory, Shenzhen, Guangdong 518000, China
| | - Mao Pang
- Department of Spine Surgery, the Third Affiliated Hospital of Sun Yat-sen University, Guangdong Provincial Center for Engineering and Technology Research of Minimally Invasive Spine Surgery, Guangzhou, Guangdong 510630, China
| | - Jianxun Xia
- Department of Basic Medical Sciences, Yunkang School of Medicine and Health, Nanfang College, Guangzhou, Guangdong 510970, China,Corresponding author.
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Xue M, Zhou SB, Liu RH, Chen QY, Zhuo M, Li XH. NMDA Receptor-Dependent Synaptic Depression in Potentiated Synapses of the Anterior Cingulate Cortex of adult Mice. Mol Pain 2021; 17:17448069211018045. [PMID: 34024172 PMCID: PMC8141994 DOI: 10.1177/17448069211018045] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Long-term potentiation (LTP) is an important molecular mechanism for chronic pain in the anterior cingulate cortex (ACC), a key cortical region for pain perception and emotional regulation. Inhibiting ACC LTP via various manipulations or pharmacological treatments blocks chronic pain. Long-term depression (LTD) is another form of synaptic plasticity in the ACC, which is also proved to be involved in the mechanisms of chronic pain. However, less is known about the interactive relationship between LTP and LTD in the ACC. Whether the synaptic depression could be induced after synaptic LTP in the ACC is not clear. In the present study, we used multi-channel field potential recording systems to study synaptic depression after LTP in the ACC of adult mice. We found that low frequency stimulus (LFS: 1 Hz, 15 min) inhibited theta burst stimulation (TBS)-induced LTP at 30 min after the induction of LTP. However, LFS failed to induce depression at 90 min after the induction of LTP. Furthermore, NMDA receptor antagonist AP-5 blocked the induction of synaptic depression after potentiation. The GluN2B-selective antagonist Ro25-6981 also inhibited the phenomenon in the ACC, while the GluN2A-selective antagonist NVP-AAM077 and the GluN2C/D-selective antagonist PPDA and UBP145 had no any significant effect. These results suggest that synaptic LTP can be depressed by LTD in a time dependent manner, and GluN2B-containing NMDA receptors play important roles in this form of synaptic depression.
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Affiliation(s)
- Man Xue
- Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an, China.,Institute of Brain Research, Qingdao International Academician Park, Qingdao, China
| | - Si-Bo Zhou
- Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an, China.,Institute of Brain Research, Qingdao International Academician Park, Qingdao, China
| | - Ren-Hao Liu
- Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an, China.,Institute of Brain Research, Qingdao International Academician Park, Qingdao, China
| | - Qi-Yu Chen
- Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an, China.,Institute of Brain Research, Qingdao International Academician Park, Qingdao, China
| | - Min Zhuo
- Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an, China.,Institute of Brain Research, Qingdao International Academician Park, Qingdao, China.,Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Xu-Hui Li
- Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an, China.,Institute of Brain Research, Qingdao International Academician Park, Qingdao, China.,Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
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Chu WG, Wang FD, Sun ZC, Ma SB, Wang X, Han WJ, Wang F, Bai ZT, Wu SX, Freichel M, Xie RG, Luo C. TRPC1/4/5 channels contribute to morphine-induced analgesic tolerance and hyperalgesia by enhancing spinal synaptic potentiation and structural plasticity. FASEB J 2020; 34:8526-8543. [PMID: 32359120 DOI: 10.1096/fj.202000154rr] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Revised: 04/15/2020] [Accepted: 04/16/2020] [Indexed: 02/10/2024]
Abstract
Opioid analgesics remain the mainstay for managing intractable chronic pain, but their use is limited by detrimental side effects such as analgesic tolerance and hyperalgesia. Calcium-dependent synaptic plasticity is a key determinant in opiates tolerance and hyperalgesia. However, the exact substrates for this calcium-dependent synaptic plasticity in mediating these maladaptive processes are largely unknown. Canonical transient receptor potential 1, 4, and 5 (TRPC1, 4, 5) proteins assemble into heteromultimeric nonselective cation channels with high Ca2+ permeability and influence various neuronal functions. However, whether and how TRPC1/4/5 channels contribute to the development of opiates tolerance and hyperalgesia remains elusive. Here, we show that TRPC1/4/5 channels contribute to the generation of morphine tolerance and hyperalgesia. Chronic morphine exposure leads to upregulation of TRPC1/4/5 channels in the spinal cord. Spinally expressed TRPC1, TPRC4, and TRPC5 are required for chronic morphine-induced synaptic long-term potentiation (LTP) as well as remodeling of synaptic spines in the dorsal horn, thereby orchestrating functional and structural plasticity during the course of morphine-induced hyperalgesia and tolerance. These effects are attributed to TRPC1/4/5-mediated Ca2+ elevation in the spinal dorsal horn induced by chronic morphine treatment. This study identifies TRPC1/4/5 channels as a promising novel target to prevent the unwanted morphine tolerance and hyperalgesia.
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Affiliation(s)
- Wen-Guang Chu
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medical University, Xi'an, China
| | - Fu-Dong Wang
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medical University, Xi'an, China
- The Fourth Regiment, School of Basic Medicine, Fourth Military Medical University, Xi'an, China
| | - Zhi-Chuan Sun
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medical University, Xi'an, China
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, Xi'an, China
| | - Sui-Bin Ma
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medical University, Xi'an, China
| | - Xu Wang
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medical University, Xi'an, China
- Research Center for Resource Polypeptide Drugs & College of Life Sciences, Yanan University, Yanan, China
| | - Wen-Juan Han
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medical University, Xi'an, China
| | - Fei Wang
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medical University, Xi'an, China
| | - Zhan-Tao Bai
- Research Center for Resource Polypeptide Drugs & College of Life Sciences, Yanan University, Yanan, China
| | - Sheng-Xi Wu
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medical University, Xi'an, China
| | - Marc Freichel
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
| | - Rou-Gang Xie
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medical University, Xi'an, China
| | - Ceng Luo
- Department of Neurobiology, School of Basic Medicine, Fourth Military Medical University, Xi'an, China
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Zheng Y, Zhou Y, Wu Q, Yue J, Ying X, Li S, Lou X, Yang G, Tu W, Zhou K, Jiang S. Effect of electroacupuncture on the expression of P2 × 4, GABAA γ 2 and long-term potentiation in spinal cord of rats with neuropathic pain. Brain Res Bull 2020; 162:1-10. [PMID: 32428626 DOI: 10.1016/j.brainresbull.2020.04.020] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 03/10/2020] [Accepted: 04/27/2020] [Indexed: 12/19/2022]
Abstract
OBJECTIVE To observe the impacts of electroacupuncture (EA) stimulation at "Zusanli and Kunlun Points" on spinal dorsal horn microglia activation in L5 spinal nerve ligation (SNL) rats and BNDF, P2 × 4 and GABAAγ2, and the changes in spinal dorsal horn synaptic plasticity in model rats. METHODS Adult male SD rats (180-220 g) were selected and randomly divided into 6 groups, including the sham group, the SNL group, the SNL + EA group, the SNL+5-BDBD group, the SNL + EA + 5-BDBD group and the SNL + FEA group. The changes in the Iba-1, BDNF, P2 × 4 and GABAAγ2 in the spinal cord of rats were observed by Western blotting, immunofluorescence, RT-PCR and other techniques; the long-term changes in the potential after the excitatory synapse of the spinal dorsal horn in rats were observed by in vivo electrophysiological technique. RESULTS After 7 days of intervention, the fluorescence intensity (FI) of P2 × 4 and Iba-1 in the SNL + EA group was lower than that in the SNL group and higher than that in the sham group(P < 0.01), but the FI of GABAAγ2 was higher than that in the SNL group(P < 0.01); the expression of Iba-1, BDNF and P2 × 4 proteins in the SNL + EA group, the SNL+5-BDBD group and the SNL + EA + 5-BDBD group was significantly lower than that in the SNL + FEA group(P < 0.05), but the expression of GABAAγ2 protein was higher (P < 0.05); after treatment with EA, the expression levels of Iba-1 mRNA and P2 × 4 mRNA in the SNL + EA group were lower than those in the SNL group(P < 0.01), but the expression levels of GABAAγ2 mRNA were higher (P < 0.01). Meanwhile, long-term potentiation changes could not be induced in the SNL + EA group. CONCLUSION The EA stimulation at "Zusanli" and "Kunlun" points can improve the pain threshold of rats with neuropathic pain (NP), inhibit the excitatory postsynaptic potential (EPSP), and weaken the excitatory transmission efficiency between synapses during NP.
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Affiliation(s)
- Yuyin Zheng
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Ye Zhou
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Qiaoyun Wu
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jingjing Yue
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xinwang Ying
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Sisi Li
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xinfa Lou
- Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Guanhu Yang
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Wenzhan Tu
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China.
| | - Kecheng Zhou
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China.
| | - Songhe Jiang
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China.
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Intracellular Calcium Responses Encode Action Potential Firing in Spinal Cord Lamina I Neurons. J Neurosci 2020; 40:4439-4456. [PMID: 32341097 DOI: 10.1523/jneurosci.0206-20.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 04/05/2020] [Accepted: 04/19/2020] [Indexed: 12/19/2022] Open
Abstract
Maladaptive plasticity of neurons in lamina I of the spinal cord is a lynchpin for the development of chronic pain, and is critically dependent on intracellular calcium signaling. However, the relationship between neuronal activity and intracellular calcium in these neurons is unknown. Here we combined two-photon calcium imaging with whole-cell electrophysiology to determine how action potential firing drives calcium responses within subcellular compartments of male rat spinal cord lamina I neurons. We found that single action potentials generated at the soma increase calcium concentration in the somatic cytosol and nucleus, and these calcium responses invade dendrites and dendritic spines by active backpropagation. Calcium responses in each compartment were dependent on voltage-gated calcium channels, and somatic and nuclear calcium responses were amplified by release of calcium from ryanodine-sensitive intracellular stores. Grouping single action potential-evoked calcium responses by neuron type demonstrated their presence in all defined types, as well as a high degree of similarity in calcium responses between neuron types. With bursts of action potentials, we found that calcium responses have the capacity to encode action potential frequency and number in all compartments, with action potential number being preferentially encoded. Together, these findings indicate that intracellular calcium serves as a readout of neuronal activity within lamina I neurons, providing a unifying mechanism through which activity may regulate plasticity, including that seen in chronic pain.SIGNIFICANCE STATEMENT Despite their critical role in both acute pain sensation and chronic pain, little is known of the fundamental physiology of spinal cord lamina I neurons. This is especially the case with respect to calcium dynamics within these neurons, which could regulate maladaptive plasticity observed in chronic pain. By combining two-photon calcium imaging and patch-clamp electrophysiological recordings from lamina I neurons, we found that action potential firing induces calcium responses within the somatic cytosol, nucleus, dendrites, and dendritic spines of lamina I neurons. Our findings demonstrate the presence of actively backpropagating action potentials, shifting our understanding of how these neurons process information, such that calcium provides a mechanism for lamina I neurons to track their own activity.
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Rosenberger DC, Blechschmidt V, Timmerman H, Wolff A, Treede RD. Challenges of neuropathic pain: focus on diabetic neuropathy. J Neural Transm (Vienna) 2020; 127:589-624. [PMID: 32036431 PMCID: PMC7148276 DOI: 10.1007/s00702-020-02145-7] [Citation(s) in RCA: 112] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 01/19/2020] [Indexed: 02/07/2023]
Abstract
Neuropathic pain is a frequent condition caused by a lesion or disease of the central or peripheral somatosensory nervous system. A frequent cause of peripheral neuropathic pain is diabetic neuropathy. Its complex pathophysiology is not yet fully elucidated, which contributes to underassessment and undertreatment. A mechanism-based treatment of painful diabetic neuropathy is challenging but phenotype-based stratification might be a way to develop individualized therapeutic concepts. Our goal is to review current knowledge of the pathophysiology of peripheral neuropathic pain, particularly painful diabetic neuropathy. We discuss state-of-the-art clinical assessment, validity of diagnostic and screening tools, and recommendations for the management of diabetic neuropathic pain including approaches towards personalized pain management. We also propose a research agenda for translational research including patient stratification for clinical trials and improved preclinical models in relation to current knowledge of underlying mechanisms.
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Affiliation(s)
- Daniela C Rosenberger
- Department of Neurophysiology, Mannheim Center for Translational Neuroscience (MCTN), Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany
| | - Vivian Blechschmidt
- Department of Neurophysiology, Mannheim Center for Translational Neuroscience (MCTN), Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany
| | - Hans Timmerman
- Department of Anesthesiology, Pain Center, University Medical Center of Groningen (UMCG), University of Groningen, Groningen, The Netherlands
| | - André Wolff
- Department of Anesthesiology, Pain Center, University Medical Center of Groningen (UMCG), University of Groningen, Groningen, The Netherlands
| | - Rolf-Detlef Treede
- Department of Neurophysiology, Mannheim Center for Translational Neuroscience (MCTN), Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany.
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11
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Martín M, Béjar J, Chávez D, Ramírez-Morales A, Hernández E, Moreno L, Contreras-Hernández E, Glusman S, Cortés U, Rudomin P. Supraspinal Shaping of Adaptive Transitions in the State of Functional Connectivity Between Segmentally Distributed Dorsal Horn Neuronal Populations in Response to Nociception and Antinociception. Front Syst Neurosci 2019; 13:47. [PMID: 31616259 PMCID: PMC6775247 DOI: 10.3389/fnsys.2019.00047] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 08/26/2019] [Indexed: 11/13/2022] Open
Abstract
In the anesthetized cat the correlation between the ongoing cord dorsum potentials (CDPs) recorded from different lumbar spinal segments has a non-random structure, suggesting relatively stable patterns of functional connectivity between the dorsal horn neuronal ensembles involved in the generation of these potentials. During the nociception induced by the intradermic injection of capsaicin, the patterns of segmental correlation between the spontaneous CDPs acquire other non-random configurations that are temporarily reversed to their pre-capsaicin state by the systemic injection of lidocaine, a procedure known to decrease the manifestation of neuropathic pain in both animals and humans. We have now extended these studies and utilized machine learning for the automatic extraction and selection of particular classes of CDPs according to their shapes and amplitudes. By using a Markovian analysis, we disclosed the transitions between the different kinds of CDPs induced by capsaicin and lidocaine and constructed a global model based on the changes in the behavior of the CDPs generated along the whole set of lumbar segments. This allowed the identification of the different states of functional connectivity within the whole ensemble of dorsal horn neurones attained during nociception and their transitory reversal by systemic administration of lidocaine in preparations with the intact neuroaxis and after spinalization. The present observations provide additional information on the state of self-organized criticality that leads to the adaptive behavior of the dorsal horn neuronal networks during nociception and antinociception both shaped by supraspinal descending influences.
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Affiliation(s)
- Mario Martín
- BarcelonaTech, Universitat Politècnica de Catalunya, Catalonia, Spain.,Barcelona Supercomputing Center, Catalonia, Spain
| | - Javier Béjar
- BarcelonaTech, Universitat Politècnica de Catalunya, Catalonia, Spain.,Barcelona Supercomputing Center, Catalonia, Spain
| | - Diógenes Chávez
- Department of Physiology, Biophysics and Neurosciences, Center for Research and Advanced Studies, National Polytechnic Institute, Mexico City, Mexico
| | - Adrian Ramírez-Morales
- Department of Physiology, Biophysics and Neurosciences, Center for Research and Advanced Studies, National Polytechnic Institute, Mexico City, Mexico
| | - Edson Hernández
- Department of Physiology, Biophysics and Neurosciences, Center for Research and Advanced Studies, National Polytechnic Institute, Mexico City, Mexico
| | - Leonardo Moreno
- Department of Physiology, Biophysics and Neurosciences, Center for Research and Advanced Studies, National Polytechnic Institute, Mexico City, Mexico
| | - Enrique Contreras-Hernández
- Department of Physiology, Biophysics and Neurosciences, Center for Research and Advanced Studies, National Polytechnic Institute, Mexico City, Mexico
| | - Silvio Glusman
- Department of Physiology, Biophysics and Neurosciences, Center for Research and Advanced Studies, National Polytechnic Institute, Mexico City, Mexico.,Stroger Cook County Hospital, Chicago, IL, United States
| | - Ulises Cortés
- BarcelonaTech, Universitat Politècnica de Catalunya, Catalonia, Spain.,Barcelona Supercomputing Center, Catalonia, Spain
| | - Pablo Rudomin
- Department of Physiology, Biophysics and Neurosciences, Center for Research and Advanced Studies, National Polytechnic Institute, Mexico City, Mexico.,El Colegio Nacional, Mexico City, Mexico
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12
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Spinal DN-9, a Peptidic Multifunctional Opioid/Neuropeptide FF Agonist Produced Potent Nontolerance Forming Analgesia With Limited Side Effects. THE JOURNAL OF PAIN 2019; 21:477-493. [PMID: 31521796 DOI: 10.1016/j.jpain.2019.08.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 08/11/2019] [Accepted: 08/25/2019] [Indexed: 11/20/2022]
Abstract
The development of multitarget opioid drugs has emerged as an attractive therapeutic strategy to eliminate opioid-related side effects. Our previous study developed a series of opioid and neuropeptide FF pharmacophore-containing chimeric peptides, including DN-9 (Tyr-D.Ala-Gly-NMe.Phe-Gly-Pro-Gln-Arg-Phe-NH2), which produced potent nontolerance forming analgesia at the supraspinal level. In the present study, the antinociceptive effects of DN-9 in a series of preclinical pain models and the potential side-effects were investigated at the spinal level in mice. In the tail-flick test, intrathecal injection of DN-9 produced potent analgesia with an ED50 value at 1.33 pmol, and the spinal antinociception of DN-9 was mainly mediated by μ- and κ-opioid receptors. In addition, DN-9-induced spinal antinociception was augmented by the neuropeptide FF receptors antagonist. Furthermore, DN-9 could decrease both the frequency and amplitude of sEPSCs in lamina IIo neurons of the spinal cord, which were mediated by opioid receptors. In contrast to morphine, chronic intrathecal treatments with DN-9 did not induce analgesic tolerance, c-Fos expression or microglial activation. Intrathecal injection of DN-9 showed potent analgesia with antinociceptive ED50 values between .66 and 55.04 pmol in different pain models, including the formalin test, acetic acid-induced writhing test, carrageenan-induced inflammatory pain and neuropathic pain. Moreover, DN-9 did not show side effects in locomotor function and coordination, gastrointestinal transit inhibition, the cardiovascular system, and body temperature regulation at antinociceptive doses. Taken together, the present study showed DN-9 produced effective, nontolerance forming analgesia with reduced side effects at the spinal level. DN-9 might be a promising compound for developing multifunctional opioid analgesics with limited adverse effects. PERSPECTIVE: This article presents the potent and nontolerance forming analgesia effects of DN-9 in a series of preclinical pain models with less opioid related adverse effects at the spinal level in mice. This study also demonstrates that DN-9 has translational potential into an intrathecal analgesic.
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13
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Yang F, Duan W, Huang Q, Chen Z, Ford N, Gao X, Sivanesan E, Sarma SV, Vera-Portocarrero LP, Linderoth B, Raja SN, Guan Y. Modulation of Spinal Nociceptive Transmission by Sub-Sensory Threshold Spinal Cord Stimulation in Rats After Nerve Injury. Neuromodulation 2019; 23:36-45. [PMID: 31162783 DOI: 10.1111/ner.12975] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/10/2019] [Accepted: 05/01/2019] [Indexed: 01/23/2023]
Abstract
OBJECTIVES High-frequency spinal cord stimulation (SCS) administered below the sensory threshold (subparesthetic) can inhibit pain, but the mechanisms remain obscure. We examined how different SCS paradigms applied at intensities below the threshold of Aβ-fiber activation (sub-sensory threshold) affect spinal nociceptive transmission in rats after an L5 spinal nerve ligation (SNL). MATERIALS AND METHODS Electrophysiology was used to record local field potential (LFP) at L4 spinal cord before, during, and 0-60 min after SCS in SNL rats. LFP was evoked by high-intensity paired-pulse test stimulation (5 mA, 0.2 msec, 400 msec interval) at the sciatic nerve. Epidural SCS was delivered through a miniature electrode placed at T13-L1 and L2-L3 spinal levels. Four patterns of SCS (200 Hz, 1 msec; 500 Hz, 0.5 msec; 1200 Hz; 0.2 msec; 10,000 Hz, 0.024 msec, 30 min, bipolar) were tested at 90% Aβ-threshold as a subthreshold intensity. As a positive control, traditional SCS (50 Hz, 0.2 msec) was tested at 100% Aβ-plateau as a suprathreshold intensity. RESULTS Traditional suprathreshold SCS at T13-L1 level significantly reduced LFP to C-fiber inputs (C-LFP). Subthreshold SCS of 200 and 500 Hz, but not 1200 or 10,000 Hz, also reduced C-LFP, albeit to a lesser extent than did traditional SCS (n = 7-10/group). When SCS was applied at the L2-L3 level, only traditional SCS and subthreshold SCS of 200 Hz inhibited C-LFP (n = 8-10/group). CONCLUSIONS Traditional suprathreshold SCS acutely inhibits spinal nociceptive transmission. Low-frequency subthreshold SCS with a long pulse width (200 Hz, 1 msec), but not higher-frequency SCS, also attenuates C-LFP.
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Affiliation(s)
- Fei Yang
- Department of Neurobiology, School of Basic Medical Sciences, Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China.,Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Wanru Duan
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA.,Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Qian Huang
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Zhiyong Chen
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Neil Ford
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Xinyan Gao
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
| | - Eellan Sivanesan
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Sridevi V Sarma
- Department of Biomedical Engineering, Institute for Computational Medicine, Johns Hopkins University, Baltimore, MD, USA
| | | | - Bengt Linderoth
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Srinivasa N Raja
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Yun Guan
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA.,Department of Neurological Surgery, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
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14
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Waataja JJ, Peterson CD, Verma H, Goracke-Postle CJ, Séguéla P, Delpire E, Wilcox GL, Fairbanks CA. Agmatine preferentially antagonizes GluN2B-containing N-methyl-d-aspartate receptors in spinal cord. J Neurophysiol 2019; 121:662-671. [PMID: 30427758 PMCID: PMC6397392 DOI: 10.1152/jn.00172.2018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Revised: 11/12/2018] [Accepted: 11/14/2018] [Indexed: 12/28/2022] Open
Abstract
The role of the N-methyl-d-aspartate receptor (NMDAr) as a contributor to maladaptive neuroplasticity underlying the maintenance of chronic pain is well established. Agmatine, an NMDAr antagonist, has been shown to reverse tactile hypersensitivity in rodent models of neuropathic pain while lacking the side effects characteristic of global NMDAr antagonism, including sedation and motor impairment, indicating a likely subunit specificity of agmatine's NMDAr inhibition. The present study assessed whether agmatine inhibits subunit-specific NMDAr-mediated current in the dorsal horn of mouse spinal cord slices. We isolated NMDAr-mediated excitatory postsynaptic currents (EPSCs) in small lamina II dorsal horn neurons evoked by optogenetic stimulation of Nav1.8-containing nociceptive afferents. We determined that agmatine abbreviated the amplitude, duration, and decay constant of NMDAr-mediated EPSCs similarly to the application of the GluN2B antagonist ifenprodil. In addition, we developed a site-specific knockdown of the GluN2B subunit of the NMDAr. We assessed whether agmatine and ifenprodil were able to inhibit NMDAr-mediated current in the spinal cord dorsal horn of mice lacking the GluN2B subunit of the NMDAr by analysis of electrically evoked EPSCs. In control mouse spinal cord, agmatine and ifenprodil both inhibited amplitude and accelerated the decay kinetics. However, agmatine and ifenprodil failed to attenuate the decay kinetics of NMDAr-mediated EPSCs in the GluN2B-knockdown mouse spinal cord. The present study indicates that agmatine preferentially antagonizes GluN2B-containing NMDArs in mouse dorsal horn neurons. NEW & NOTEWORTHY Our study is the first to report that agmatine preferentially antagonizes the GluN2B receptor subunit of the N-methyl-d-aspartate (NMDA) receptor in spinal cord. The preferential targeting of GluN2B receptor is consistent with the pharmacological profile of agmatine in that it reduces chronic pain without the motor side effects commonly seen with non-subunit-selective NMDA receptor antagonists.
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Affiliation(s)
- Jonathan J Waataja
- Department of Neuroscience, University of Minnesota , Minneapolis, Minnesota
| | - Cristina D Peterson
- Department of Experimental and Clinical Pharmacology, University of Minnesota , Minneapolis, Minnesota
| | - Harsha Verma
- Department of Pharmaceutics, University of Minnesota , Minneapolis, Minnesota
| | | | - Philippe Séguéla
- Department of Neurology and Neurosurgery, McGill University , Montreal, Quebec , Canada
| | - Eric Delpire
- Department of Anesthesiology, Vanderbilt School of Medicine , Nashville, Tennessee
| | - George L Wilcox
- Department of Neuroscience, University of Minnesota , Minneapolis, Minnesota
- Department of Pharmacology, University of Minnesota , Minneapolis, Minnesota
- Department of Dermatology, University of Minnesota , Minneapolis, Minnesota
| | - Carolyn A Fairbanks
- Department of Neuroscience, University of Minnesota , Minneapolis, Minnesota
- Department of Experimental and Clinical Pharmacology, University of Minnesota , Minneapolis, Minnesota
- Department of Pharmaceutics, University of Minnesota , Minneapolis, Minnesota
- Department of Pharmacology, University of Minnesota , Minneapolis, Minnesota
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15
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Martin LJ, Acland EL, Cho C, Gandhi W, Chen D, Corley E, Kadoura B, Levy T, Mirali S, Tohyama S, Khan S, MacIntyre LC, Carlson EN, Schweinhardt P, Mogil JS. Male-Specific Conditioned Pain Hypersensitivity in Mice and Humans. Curr Biol 2019; 29:192-201.e4. [DOI: 10.1016/j.cub.2018.11.030] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 09/24/2018] [Accepted: 11/09/2018] [Indexed: 12/19/2022]
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Abstract
Opioids are the most commonly used and effective analgesic treatments for severe pain, but they have recently come under scrutiny owing to epidemic levels of abuse and overdose. These compounds act on the endogenous opioid system, which comprises four G protein-coupled receptors (mu, delta, kappa, and nociceptin) and four major peptide families (β-endorphin, enkephalins, dynorphins, and nociceptin/orphanin FQ). In this review, we first describe the functional organization and pharmacology of the endogenous opioid system. We then summarize current knowledge on the signaling mechanisms by which opioids regulate neuronal function and neurotransmission. Finally, we discuss the loci of opioid analgesic action along peripheral and central pain pathways, emphasizing the pain-relieving properties of opioids against the affective dimension of the pain experience.
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Affiliation(s)
- Gregory Corder
- Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University, Palo Alto, California 94304, USA; .,Department of Molecular and Cellular Physiology, Stanford University, Palo Alto, California 94304, USA.,Department of Neurosurgery, Stanford University, Palo Alto, California 94304, USA.,Stanford Neurosciences Institute, Palo Alto, California 94304, USA
| | - Daniel C Castro
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, Missouri 63130, USA;
| | - Michael R Bruchas
- Department of Anesthesiology, Washington University in St. Louis, St. Louis, Missouri 63130, USA; .,Division of Basic Research, Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63130, USA.,Washington University Pain Center, Washington University School of Medicine, St. Louis, Missouri 63130, USA.,Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri 63130, USA.,Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Grégory Scherrer
- Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University, Palo Alto, California 94304, USA; .,Department of Molecular and Cellular Physiology, Stanford University, Palo Alto, California 94304, USA.,Department of Neurosurgery, Stanford University, Palo Alto, California 94304, USA.,Stanford Neurosciences Institute, Palo Alto, California 94304, USA.,New York Stem Cell Foundation - Robertson Investigator, Stanford University, Palo Alto, California 94304, USA
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17
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Contreras‐Hernández E, Chávez D, Hernández E, Velázquez E, Reyes P, Béjar J, Martín M, Cortés U, Glusman S, Rudomin P. Supraspinal modulation of neuronal synchronization by nociceptive stimulation induces an enduring reorganization of dorsal horn neuronal connectivity. J Physiol 2018; 596:1747-1776. [PMID: 29451306 PMCID: PMC5924834 DOI: 10.1113/jp275228] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 02/12/2018] [Indexed: 12/21/2022] Open
Abstract
KEY POINTS The state of central sensitization induced by the intradermic injection of capsaicin leads to structured (non-random) changes in functional connectivity between dorsal horn neuronal populations distributed along the spinal lumbar segments in anaesthetized cats. The capsaicin-induced changes in neuronal connectivity and the concurrent increase in secondary hyperalgesia are transiently reversed by the systemic administration of small doses of lidocaine, a clinically effective procedure to treat neuropathic pain. The effects of both capsaicin and lidocaine are greatly attenuated in spinalized preparations, showing that supraspinal influences play a significant role in the shaping of nociceptive-induced changes in dorsal horn functional neuronal connectivity. We conclude that changes in functional connectivity between segmental populations of dorsal horn neurones induced by capsaicin and lidocaine result from a cooperative adaptive interaction between supraspinal and spinal neuronal networks, a process that may have a relevant role in the pathogenesis of chronic pain and analgesia. ABSTRACT Despite a profusion of information on the molecular and cellular mechanisms involved in the central sensitization produced by intense nociceptive stimulation, the changes in the patterns of functional connectivity between spinal neurones associated with the development of secondary hyperalgesia and allodynia remain largely unknown. Here we show that the state of central sensitization produced by the intradermal injection of capsaicin is associated with structured transformations in neuronal synchronization that lead to an enduring reorganization of the functional connectivity within a segmentally distributed ensemble of dorsal horn neurones. These changes are transiently reversed by the systemic administration of small doses of lidocaine, a clinically effective procedure to treat neuropathic pain. Lidocaine also reduces the capsaicin-induced facilitation of the spinal responses evoked by weak mechanical stimulation of the skin in the region of secondary but not primary hyperalgesia. The effects of both intradermic capsaicin and systemic lidocaine on the segmental correlation and coherence between ongoing cord dorsum potentials and on the responses evoked by tactile stimulation in the region of secondary hyperalgesia are greatly attenuated in spinalized preparations, showing that supraspinal influences are involved in the reorganization of the nociceptive-induced structured patterns of dorsal horn neuronal connectivity. We conclude that the structured reorganization of the functional connectivity between the dorsal horn neurones induced by capsaicin nociceptive stimulation results from cooperative interactions between supraspinal and spinal networks, a process that may have a relevant role in the shaping of the spinal state in the pathogenesis of chronic pain and analgesia.
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Affiliation(s)
- E. Contreras‐Hernández
- Department of PhysiologyCentro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalMéxico
| | - D. Chávez
- Department of PhysiologyCentro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalMéxico
| | - E. Hernández
- Department of PhysiologyCentro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalMéxico
| | - E. Velázquez
- Department of PhysiologyCentro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalMéxico
| | - P. Reyes
- Department of PhysiologyCentro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalMéxico
| | - J. Béjar
- Universidad Politécnica de CatalunyaBarcelonaTechCataloniaSpain
| | - M. Martín
- Universidad Politécnica de CatalunyaBarcelonaTechCataloniaSpain
| | - U. Cortés
- Universidad Politécnica de CatalunyaBarcelonaTechCataloniaSpain
- Barcelona Supercomputing CenterCataloniaSpain
| | - S. Glusman
- Department of PhysiologyCentro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalMéxico
- Stroger Cook County HospitalChicagoIllinoisUSA
| | - P. Rudomin
- Department of PhysiologyCentro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalMéxico
- El Colegio NacionalMéxico
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18
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Shi C, Liu Y, Zhang W, Lei Y, Lu C, Sun R, Sun Y, Jiang M, Gu X, Ma Z. Intraoperative electroacupuncture relieves remifentanil-induced postoperative hyperalgesia via inhibiting spinal glial activation in rats. Mol Pain 2018; 13:1744806917725636. [PMID: 28825338 PMCID: PMC5570117 DOI: 10.1177/1744806917725636] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Background Accumulating studies have suggested that remifentanil, the widely-used opioid analgesic in clinical anesthesia, can activate the pronociceptive systems and enhance postoperative pain. Glial cells are thought to be implicated in remifentanil-induced hyperalgesia. Electroacupuncture is a complementary therapy to relieve various pain conditions with few side effects, and glial cells may be involved in its antinociceptive effect. In this study, we investigated whether intraoperative electroacupuncture could relieve remifentanil-induced postoperative hyperalgesia by inhibiting the activation of spinal glial cells, the production of spinal proinflammatory cytokines, and the activation of spinal mitogen-activated protein kinases. Methods A rat model of remifentanil-induced postoperative hyperalgesia was used in this study. Electroacupuncture during surgery was conducted at bilateral Zusanli (ST36) acupoints. Behavior tests, including mechanical allodynia and thermal hyperalgesia, were performed at different time points. Astrocytic marker glial fibrillary acidic protein, microglial marker Iba1, proinflammatory cytokines, and phosphorylated mitogen-activated protein kinases in the spinal cord were detected by Western blot and/or immunofluorescence. Results Mechanical allodynia and thermal hyperalgesia were induced by both surgical incision and remifentanil infusion, and remifentanil infusion significantly exaggerated and prolonged incision-induced pronociceptive effects. Glial fibrillary acidic protein, Iba1, proinflammatory cytokines (interleukin-1β and tumor necrosis factor-α), and phosphorylated mitogen-activated protein kinases (p-p38, p-JNK, and p-ERK1/2) were upregulated after surgical incision, remifentanil infusion, and especially after their combination. Intraoperative electroacupuncture significantly attenuated incision- and/or remifentanil-induced pronociceptive effects, spinal glial activation, proinflammatory cytokine upregulation, and phosphorylated mitogen-activated protein kinase upregulation. Conclusions Our study suggests that remifentanil-induced postoperative hyperalgesia can be relieved by intraoperative electroacupuncture via inhibiting the activation of spinal glial cells, the upregulation of spinal proinflammatory cytokines, and the activation of spinal mitogen-activated protein kinases.
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Affiliation(s)
- Changxi Shi
- 1 Nanjing Drum Tower Hospital Clinical College of Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Jiangsu Province, China.,2 Department of Anesthesiology, Jiangsu Province Hospital on Integration of Chinese and Western Medicine, Nanjing University of Chinese Medicine, Jiangsu Province, China
| | - Yue Liu
- 3 Department of Anesthesiology, Drum Tower Hospital, Medical School of Nanjing University, Jiangsu Province, China
| | - Wei Zhang
- 3 Department of Anesthesiology, Drum Tower Hospital, Medical School of Nanjing University, Jiangsu Province, China
| | - Yishan Lei
- 3 Department of Anesthesiology, Drum Tower Hospital, Medical School of Nanjing University, Jiangsu Province, China
| | - Cui'e Lu
- 3 Department of Anesthesiology, Drum Tower Hospital, Medical School of Nanjing University, Jiangsu Province, China
| | - Rao Sun
- 3 Department of Anesthesiology, Drum Tower Hospital, Medical School of Nanjing University, Jiangsu Province, China
| | - Yu'e Sun
- 3 Department of Anesthesiology, Drum Tower Hospital, Medical School of Nanjing University, Jiangsu Province, China
| | - Ming Jiang
- 3 Department of Anesthesiology, Drum Tower Hospital, Medical School of Nanjing University, Jiangsu Province, China
| | - Xiaoping Gu
- 3 Department of Anesthesiology, Drum Tower Hospital, Medical School of Nanjing University, Jiangsu Province, China
| | - Zhengliang Ma
- 3 Department of Anesthesiology, Drum Tower Hospital, Medical School of Nanjing University, Jiangsu Province, China
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19
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Magerl W, Hansen N, Treede RD, Klein T. The human pain system exhibits higher-order plasticity (metaplasticity). Neurobiol Learn Mem 2018; 154:112-120. [PMID: 29631001 DOI: 10.1016/j.nlm.2018.04.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Revised: 02/21/2018] [Accepted: 04/05/2018] [Indexed: 01/10/2023]
Abstract
The human pain system can be bidirectionally modulated by high-frequency (HFS; 100 Hz) and low-frequency (LFS; 1 Hz) electrical stimulation of nociceptors leading to long-term potentiation or depression of pain perception (pain-LTP or pain-LTD). Here we show that priming a test site by very low-frequency stimulation (VLFS; 0.05 Hz) prevented pain-LTP probably by elevating the threshold (set point) for pain-LTP induction. Conversely, prior HFS-induced pain-LTP was substantially reversed by subsequent VLFS, suggesting that preceding HFS had primed the human nociceptive system for pain-LTD induction by VLFS. In contrast, the pain elicited by the pain-LTP-precipitating conditioning HFS stimulation remained unaffected. In aggregate these experiments demonstrate that the human pain system expresses two forms of higher-order plasticity (metaplasticity) acting in either direction along the pain-LTD to pain-LTP continuum with similar shifts in thresholds for LTD and LTP as in synaptic plasticity, indicating intriguing new mechanisms for the prevention of pain memory and the erasure of hyperalgesia related to an already established pain memory trace. There were no apparent gender differences in either pain-LTP or metaplasticity of pain-LTP. However, individual subjects appeared to present with an individual balance of pain-LTD to pain-LTP (a pain plasticity "fingerprint").
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Affiliation(s)
- Walter Magerl
- Department of Neurophysiology, Center of Biomedicine and Medical Technology Mannheim (CBTM), Medical Faculty Mannheim, Ruprecht Karl-University Heidelberg, Ludolf Krehl-Str. 13-17, 68167 Mannheim, Germany.
| | - Niels Hansen
- Department of Neurophysiology, Center of Biomedicine and Medical Technology Mannheim (CBTM), Medical Faculty Mannheim, Ruprecht Karl-University Heidelberg, Ludolf Krehl-Str. 13-17, 68167 Mannheim, Germany; Department of Psychiatry and Psychotherapy & Department of Epileptology, University Hospital Bonn, Sigmund-Freud-Straße 25, 53105 Bonn, Germany
| | - Rolf-Detlef Treede
- Department of Neurophysiology, Center of Biomedicine and Medical Technology Mannheim (CBTM), Medical Faculty Mannheim, Ruprecht Karl-University Heidelberg, Ludolf Krehl-Str. 13-17, 68167 Mannheim, Germany
| | - Thomas Klein
- Department of Neurophysiology, Center of Biomedicine and Medical Technology Mannheim (CBTM), Medical Faculty Mannheim, Ruprecht Karl-University Heidelberg, Ludolf Krehl-Str. 13-17, 68167 Mannheim, Germany
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20
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Liu S, Yao JL, Wan XX, Song ZJ, Miao S, Zhao Y, Wang XL, Liu YP. Sonic hedgehog signaling in spinal cord contributes to morphine-induced hyperalgesia and tolerance through upregulating brain-derived neurotrophic factor expression. J Pain Res 2018; 11:649-659. [PMID: 29662325 PMCID: PMC5892616 DOI: 10.2147/jpr.s153544] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Purpose Preventing opioid-induced hyperalgesia and tolerance continues to be a major clinical challenge, and the underlying mechanisms of hyperalgesia and tolerance remain elusive. Here, we investigated the role of sonic hedgehog (Shh) signaling in opioid-induced hyperalgesia and tolerance. Methods Shh signaling expression, behavioral changes, and neurochemical alterations induced by morphine were analyzed in male adult CD-1 mice with repeated administration of morphine. To investigate the contribution of Shh to morphine-induced hyperalgesia (MIH) and tolerance, Shh signaling inhibitor cyclopamine and Shh small interfering RNA (siRNA) were used. To explore the mechanisms of Shh signaling in MIH and tolerance, brain-derived neurotrophic factor (BDNF) inhibitor K252 and anti-BDNF antibody were used. Results Repeated administration of morphine produced obvious hyperalgesia and tolerance. The behavioral changes were correlated with the upregulation and activation of morphine treatment-induced Shh signaling. Pharmacologic and genetic inhibition of Shh signaling significantly delayed the generation of MIH and tolerance and associated neurochemical changes. Chronic morphine administration also induced upregulation of BDNF. Inhibiting BDNF effectively delayed the generation of MIH and tolerance. The upregulation of BDNF induced by morphine was significantly suppressed by inhibiting Shh signaling. In naïve mice, exogenous activation of Shh signaling caused a rapid increase of BDNF expression, as well as thermal hyperalgesia. Inhibiting BDNF significantly suppressed smoothened agonist-induced hyperalgesia. Conclusion These findings suggest that Shh signaling may be a critical mediator for MIH and tolerance by regulating BDNF expression. Inhibiting Shh signaling, especially during the early phase, may effectively delay or suppress MIH and tolerance.
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Affiliation(s)
- Su Liu
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu, China.,Department of Anesthesiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Jun-Li Yao
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu, China.,Department of Anesthesiology, Xuzhou Children's Hospital, Xuzhou, Jiangsu, China
| | - Xin-Xin Wan
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Zhi-Jing Song
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Shuai Miao
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu, China.,Department of Anesthesiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Ye Zhao
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu, China.,Department of Anesthesiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Xiu-Li Wang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu, China.,Department of Anesthesiology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Yue-Peng Liu
- Center of Clinical Research and Translational Medicine, Lianyungang Oriental Hospital, Lianyungang, Jiangsu, China
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21
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Liu JP, He YT, Duan XL, Suo ZW, Yang X, Hu XD. Enhanced Activities of δ Subunit-containing GABAA Receptors Blocked Spinal Long-term Potentiation and Attenuated Formalin-induced Spontaneous Pain. Neuroscience 2018; 371:155-165. [DOI: 10.1016/j.neuroscience.2017.12.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 11/11/2017] [Accepted: 12/02/2017] [Indexed: 01/22/2023]
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22
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Spinal protein kinase C/extracellular signal–regulated kinase signal pathway mediates hyperalgesia priming. Pain 2018; 159:907-918. [DOI: 10.1097/j.pain.0000000000001162] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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23
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Kendall MC, Robbins ZM, Cohen A, Minn M, Benzuly SE, Triebwasser AS, McCormick ZL, Gorgone M. Selected highlights in clinical anesthesia research. J Clin Anesth 2017; 43:90-97. [DOI: 10.1016/j.jclinane.2017.10.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 10/10/2017] [Accepted: 10/13/2017] [Indexed: 12/17/2022]
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24
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Activation of cannabinoid CB1 receptor contributes to suppression of spinal nociceptive transmission and inhibition of mechanical hypersensitivity by Aβ-fiber stimulation. Pain 2017; 157:2582-2593. [PMID: 27589093 DOI: 10.1097/j.pain.0000000000000680] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Activation of Aβ-fibers is an intrinsic feature of spinal cord stimulation (SCS) pain therapy. Cannabinoid receptor type 1 (CB1) is important to neuronal plasticity and pain modulation, but its role in SCS-induced pain inhibition remains unclear. In this study, we showed that CB1 receptors are expressed in both excitatory and inhibitory interneurons in substantia gelatinosa (SG). Patch-clamp recording of the evoked excitatory postsynaptic currents (eEPSCs) in mice after spinal nerve ligation (SNL) showed that electrical stimulation of Aβ-fibers (Aβ-ES) using clinical SCS-like parameters (50 Hz, 0.2 millisecond, 10 μA) induced prolonged depression of eEPSCs to C-fiber inputs in SG neurons. Pretreatment with CB1 receptor antagonist AM251 (2 μM) reduced the inhibition of C-eEPSCs by Aβ-ES in both excitatory and inhibitory SG neurons. We further determined the net effect of Aβ-ES on spinal nociceptive transmission in vivo by recording spinal local field potential in SNL rats. Epidural SCS (50 Hz, Aβ-plateau, 5 minutes) attenuated C-fiber-evoked local field potential. This effect of SCS was partially reduced by spinal topical application of AM251 (25 μg, 50 μL), but not CB2 receptor antagonist AM630 (100 μg). Finally, intrathecal pretreatment with AM251 (50 μg, 15 μL) in SNL rats blocked the inhibition of behavioral mechanical hypersensitivity by SCS (50 Hz, 0.2 millisecond; 80% of motor threshold, 60 minutes). Our findings suggest that activation of spinal CB1 receptors may contribute to synaptic depression to high-threshold afferent inputs in SG neurons after Aβ-ES and may be involved in SCS-induced inhibition of spinal nociceptive transmission after nerve injury.
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25
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Suo ZW, Liu JP, Xue M, Yang YH, Yang X, Xie J, Hu XD. Striatal-enriched phosphatase 61 inhibited the nociceptive plasticity in spinal cord dorsal horn of rats. Neuroscience 2017; 352:97-105. [PMID: 28389375 DOI: 10.1016/j.neuroscience.2017.03.048] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Revised: 03/09/2017] [Accepted: 03/27/2017] [Indexed: 01/09/2023]
Abstract
Striatal-enriched phosphatase 61 (STEP61) is a member of intracellular protein tyrosine phosphatases, which is involved in the regulation of synaptic plasticity and a line of neuropsychiatric disorders. This protein tyrosine phosphatase is also abundant in pain-related spinal cord dorsal horn neurons. However, whether and how this tyrosine phosphatase modulates the nociceptive plasticity and behavioral hypersensitivity remain largely unknown. The present study recorded the long-term potentiation (LTP) of primary afferent C fiber-evoked field potentials in vivo in superficial dorsal horn of rats, and tested the possible role of STEP61 in spinal LTP. We found that LTP induction significantly increased STEP61 phosphorylation at Ser221 residue, a key molecular event that has been shown to impair the phosphatase activity. The STEP61 hypoactivity allowed for the activation of three substrates, GluN2B subunit-containing N-methyl-d-aspartate-subtype glutamate receptors, Src-family protein tyrosine kinase member Fyn and extracellular signal-regulated kinase 1/2, through which the thresholds for LTP induction were noticeably decreased. To reinstate STEP61 activity, we overexpressed wild-type STEP61 [STEP61(WT)] in spinal dorsal horn, finding that STEP61(WT) completely blunted LTP induction. Behavioral tests showed that LTP blockade by STEP61(WT) correlated with a long-lasting alleviation of thermal hypersensitivity and mechanical allodynia induced by chronic constriction injury of sciatic nerves. These data implicated that STEP61 exerted a negative control over spinal nociceptive plasticity, which might have therapeutic benefit in pathological pain.
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Affiliation(s)
- Zhan-Wei Suo
- Department of Molecular Pharmacology, School of Pharmacy, Lanzhou University, Lanzhou, Gansu 730000, PR China
| | - Jiang-Ping Liu
- Department of Molecular Pharmacology, School of Pharmacy, Lanzhou University, Lanzhou, Gansu 730000, PR China
| | - Man Xue
- Department of Molecular Pharmacology, School of Pharmacy, Lanzhou University, Lanzhou, Gansu 730000, PR China
| | - Yun-Hui Yang
- Department of Molecular Pharmacology, School of Pharmacy, Lanzhou University, Lanzhou, Gansu 730000, PR China
| | - Xian Yang
- Department of Molecular Pharmacology, School of Pharmacy, Lanzhou University, Lanzhou, Gansu 730000, PR China
| | - Jun Xie
- The Central Blood Station of Jiuquan, Gansu Province, PR China
| | - Xiao-Dong Hu
- Department of Molecular Pharmacology, School of Pharmacy, Lanzhou University, Lanzhou, Gansu 730000, PR China.
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26
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Prosenz J, Kloimstein H, Thaler U, Drdla-Schutting R, Sandkühler J, Gustorff B. A brief, high-dose remifentanil infusion partially reverses neuropathic pain in a subgroup of post herpetic neuralgia patients. J Clin Neurosci 2017; 40:195-197. [PMID: 28279552 DOI: 10.1016/j.jocn.2017.02.048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 02/12/2017] [Indexed: 11/27/2022]
Abstract
Mechanism-based therapy for chronic pain is desperately needed. Recent basic science research demonstrated that remifentanil can reverse long-term potentiation at C-fiber synapses in the dorsal horn of rats. In this exploratory, single group study, patients with chronic post-herpetic pain were treated with a single, one-hour, high-dose remifentanil infusion. The mean overall change of pain intensity seven days after treatment was -18 (-7.5; -28.5, 95%CI, p<0.001) points on the numeric rating scale (0-100) (-33 (±11) points amongst responders only). Eleven of 20 patients responded to treatment (≥30% reduction in pain), the mean relative reduction in pain from baseline amongst responders was 61.0%. These promising preliminary results suggest that a mechanism-based reversal of chronic pain may be impending.
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Affiliation(s)
- Julian Prosenz
- Department of Anesthesia, Intensive Care, and Pain Medicine, Vienna Human Pain Research Group, Montlearstrasse 37, Wilhelminen Hospital, 1160 Vienna, Austria; Department of Anesthesia, General Intensive Care, and Pain Therapy, Medical University of Vienna, Spitalgasse 23, 1090 Vienna, Austria.
| | - Herwig Kloimstein
- Department of Anesthesia, Intensive Care, and Pain Medicine, Vienna Human Pain Research Group, Montlearstrasse 37, Wilhelminen Hospital, 1160 Vienna, Austria.
| | - Ulrich Thaler
- Department of Anesthesia, Intensive Care, and Pain Medicine, Vienna Human Pain Research Group, Montlearstrasse 37, Wilhelminen Hospital, 1160 Vienna, Austria.
| | - Ruth Drdla-Schutting
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, 1090 Vienna, Austria.
| | - Jürgen Sandkühler
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, 1090 Vienna, Austria.
| | - Burkhard Gustorff
- Department of Anesthesia, Intensive Care, and Pain Medicine, Vienna Human Pain Research Group, Montlearstrasse 37, Wilhelminen Hospital, 1160 Vienna, Austria.
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27
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Xue M, Liu J, Yang Y, Suo Z, Yang X, Hu X. Inhibition of α5 subunit-containing GABAAreceptors facilitated spinal nociceptive transmission and plasticity. Eur J Pain 2017; 21:1061-1071. [DOI: 10.1002/ejp.1009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/12/2016] [Indexed: 01/09/2023]
Affiliation(s)
- M. Xue
- Department of Molecular Pharmacology, School of Pharmacy; Lanzhou University; China
| | - J.P. Liu
- Department of Molecular Pharmacology, School of Pharmacy; Lanzhou University; China
| | - Y.H. Yang
- Department of Molecular Pharmacology, School of Pharmacy; Lanzhou University; China
| | - Z.W. Suo
- Department of Molecular Pharmacology, School of Pharmacy; Lanzhou University; China
| | - X. Yang
- Department of Molecular Pharmacology, School of Pharmacy; Lanzhou University; China
| | - X.D. Hu
- Department of Molecular Pharmacology, School of Pharmacy; Lanzhou University; China
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28
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Huie JR, Morioka K, Haefeli J, Ferguson AR. What Is Being Trained? How Divergent Forms of Plasticity Compete To Shape Locomotor Recovery after Spinal Cord Injury. J Neurotrauma 2017; 34:1831-1840. [PMID: 27875927 DOI: 10.1089/neu.2016.4562] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Spinal cord injury (SCI) is a devastating syndrome that produces dysfunction in motor and sensory systems, manifesting as chronic paralysis, sensory changes, and pain disorders. The multi-faceted and heterogeneous nature of SCI has made effective rehabilitative strategies challenging. Work over the last 40 years has aimed to overcome these obstacles by harnessing the intrinsic plasticity of the spinal cord to improve functional locomotor recovery. Intensive training after SCI facilitates lower extremity function and has shown promise as a tool for retraining the spinal cord by engaging innate locomotor circuitry in the lumbar cord. As new training paradigms evolve, the importance of appropriate afferent input has emerged as a requirement for adaptive plasticity. The integration of kinematic, sensory, and loading force information must be closely monitored and carefully manipulated to optimize training outcomes. Inappropriate peripheral input may produce lasting maladaptive sensory and motor effects, such as central pain and spasticity. Thus, it is important to closely consider the type of afferent input the injured spinal cord receives. Here we review preclinical and clinical input parameters fostering adaptive plasticity, as well as those producing maladaptive plasticity that may undermine neurorehabilitative efforts. We differentiate between passive (hindlimb unloading [HU], limb immobilization) and active (peripheral nociception) forms of aberrant input. Furthermore, we discuss the timing of initiating exposure to afferent input after SCI for promoting functional locomotor recovery. We conclude by presenting a candidate rapid synaptic mechanism for maladaptive plasticity after SCI, offering a pharmacological target for restoring the capacity for adaptive spinal plasticity in real time.
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Affiliation(s)
- J Russell Huie
- 1 Department of Neurological Surgery, Brain and Spinal Injury Center, University of California , San Francisco, California
| | - Kazuhito Morioka
- 1 Department of Neurological Surgery, Brain and Spinal Injury Center, University of California , San Francisco, California
| | - Jenny Haefeli
- 1 Department of Neurological Surgery, Brain and Spinal Injury Center, University of California , San Francisco, California
| | - Adam R Ferguson
- 1 Department of Neurological Surgery, Brain and Spinal Injury Center, University of California , San Francisco, California.,2 San Francisco Veterans Affairs Medical Center , San Francisco, California
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29
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Gomez-Varela D, Schmidt M. Exploring novel paths towards protein signatures of chronic pain. Mol Pain 2016; 12:12/0/1744806916679658. [PMID: 27920228 PMCID: PMC5153021 DOI: 10.1177/1744806916679658] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 09/01/2016] [Accepted: 10/13/2016] [Indexed: 12/15/2022] Open
Abstract
Pain is a major symptom of many medical conditions and the worldwide number one reason for people to seek medical assistance. It affects the quality of life of patients and poses a heavy financial burden on society with high costs of treatment and lost productivity. Furthermore, the treatment of chronic pain presents a big challenge as pain therapeutics often lack efficacy and exhibit minimal safety profiles. The latter can be largely attributed to the fact that current therapies target molecules with key physiological functions throughout the body. In light of these difficulties, the identification of proteins specifically involved in chronic pain states is of paramount importance for designing selective interventions. Several profiling efforts have been employed with the aim to dissect the molecular underpinnings of chronic pain, both on the level of the transcriptome and proteome. However, generated results are often inconsistent and non-overlapping, which is largely due to inherent technical constraints. A potential solution may be offered by emerging strategies capable of performing standardized and reproducible proteome analysis, such as data-independent acquisition-mass spectrometry (DIA-MS). We have recently demonstrated the applicability of DIA-MS to interrogate chronic pain-related proteome alterations in mice. Based on our results, we aim to provide an overview on DIA-MS and its potential to contribute to the comprehensive characterization of molecular signatures underlying pain pathologies.
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Affiliation(s)
| | - Manuela Schmidt
- Max-Planck Institute of Experimental Medicine, Göttingen, Germany
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30
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Kronschläger MT, Drdla-Schutting R, Gassner M, Honsek SD, Teuchmann HL, Sandkühler J. Gliogenic LTP spreads widely in nociceptive pathways. Science 2016; 354:1144-1148. [PMID: 27934764 PMCID: PMC6145441 DOI: 10.1126/science.aah5715] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 11/01/2016] [Indexed: 12/30/2022]
Abstract
Learning and memory formation involve long-term potentiation (LTP) of synaptic strength. A fundamental feature of LTP induction in the brain is the need for coincident pre- and postsynaptic activity. This restricts LTP expression to activated synapses only (homosynaptic LTP) and leads to its input specificity. In the spinal cord, we discovered a fundamentally different form of LTP that is induced by glial cell activation and mediated by diffusible, extracellular messengers, including d-serine and tumor necrosis factor (TNF), and that travel long distances via the cerebrospinal fluid, thereby affecting susceptible synapses at remote sites. The properties of this gliogenic LTP resolve unexplained findings of memory traces in nociceptive pathways and may underlie forms of widespread pain hypersensitivity.
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Affiliation(s)
- M T Kronschläger
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, 1090 Vienna, Austria
| | - R Drdla-Schutting
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, 1090 Vienna, Austria
| | - M Gassner
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, 1090 Vienna, Austria
| | - S D Honsek
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, 1090 Vienna, Austria
| | - H L Teuchmann
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, 1090 Vienna, Austria
| | - J Sandkühler
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, Spitalgasse 4, 1090 Vienna, Austria.
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31
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Chen G, Xie RG, Gao YJ, Xu ZZ, Zhao LX, Bang S, Berta T, Park CK, Lay M, Chen W, Ji RR. β-arrestin-2 regulates NMDA receptor function in spinal lamina II neurons and duration of persistent pain. Nat Commun 2016; 7:12531. [PMID: 27538456 PMCID: PMC5477285 DOI: 10.1038/ncomms12531] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 07/08/2016] [Indexed: 02/02/2023] Open
Abstract
Mechanisms of acute pain transition to chronic pain are not fully understood. Here we demonstrate an active role of β-arrestin 2 (Arrb2) in regulating spinal cord NMDA receptor (NMDAR) function and the duration of pain. Intrathecal injection of the mu-opioid receptor agonist [D-Ala2, NMe-Phe4, Gly-ol5]-enkephalin produces paradoxical behavioural responses: early-phase analgesia and late-phase mechanical allodynia which requires NMDAR; both phases are prolonged in Arrb2 knockout (KO) mice. Spinal administration of NMDA induces GluN2B-dependent mechanical allodynia, which is prolonged in Arrb2-KO mice and conditional KO mice lacking Arrb2 in presynaptic terminals expressing Nav1.8. Loss of Arrb2 also results in prolongation of inflammatory pain and neuropathic pain and enhancement of GluN2B-mediated NMDA currents in spinal lamina IIo not lamina I neurons. Finally, spinal over-expression of Arrb2 reverses chronic neuropathic pain after nerve injury. Thus, spinal Arrb2 may serve as an intracellular gate for acute to chronic pain transition via desensitization of NMDAR. The cellular mechanisms underlying acute pain transitions to chronic pain are poorly understood. Here the authors show that the scaffolding protein β-arrestin 2 contributes to these processes via desensitization of NMDA receptors in spinal neurons.
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Affiliation(s)
- Gang Chen
- Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina 27710, USA.,Jiangsu Key Laboratory of Neuroregeneration, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China
| | - Rou-Gang Xie
- Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina 27710, USA.,Department of Anesthesiology and Pain Management, Xijing Hospital, Department of Neuroscience, Fourth Military Medical University, Xian, Shanxi 710032, China
| | - Yong-Jing Gao
- Pain Research Laboratory, Institute of Nautical Medicine, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China
| | - Zhen-Zhong Xu
- Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina 27710, USA.,Department of Neurobiology, Institute of Neuroscience, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, Zhejiang University School of Medicine, Hangzhou, Zhejiang 3100058, China
| | - Lin-Xia Zhao
- Pain Research Laboratory, Institute of Nautical Medicine, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China
| | - Sangsu Bang
- Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Temugin Berta
- Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina 27710, USA.,Pain Research Center, Department of Anesthesiology, University of Cincinnati Medical Center, Cincinnati, Ohio 45267, USA
| | - Chul-Kyu Park
- Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina 27710, USA.,Department of Physiology, College of Medicine, Gachon University, Incheon 21999, South Korea
| | - Mark Lay
- Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Wei Chen
- Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Ru-Rong Ji
- Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina 27710, USA.,Department of Neurobiology, Duke University Medical Center, Durham, North Carolina 27710, USA
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32
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Roeckel LA, Le Coz GM, Gavériaux-Ruff C, Simonin F. Opioid-induced hyperalgesia: Cellular and molecular mechanisms. Neuroscience 2016; 338:160-182. [PMID: 27346146 DOI: 10.1016/j.neuroscience.2016.06.029] [Citation(s) in RCA: 256] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 06/10/2016] [Accepted: 06/16/2016] [Indexed: 12/18/2022]
Abstract
Opioids produce strong analgesia but their use is limited by a paradoxical hypersensitivity named opioid-induced hyperalgesia (OIH) that may be associated to analgesic tolerance. In the last decades, a significant number of preclinical studies have investigated the factors that modulate OIH development as well as the cellular and molecular mechanisms underlying OIH. Several factors have been shown to influence OIH including the genetic background and sex differences of experimental animals as well as the opioid regimen. Mu opioid receptor (MOR) variants and interactions of MOR with different proteins were shown important. Furthermore, at the cellular level, both neurons and glia play a major role in OIH development. Several neuronal processes contribute to OIH, like activation of neuroexcitatory mechanisms, long-term potentiation (LTP) and descending pain facilitation. Increased nociception is also mediated by neuroinflammation induced by the activation of microglia and astrocytes. Neurons and glial cells exert synergistic effects, which contribute to OIH. The molecular actors identified include the Toll-like receptor 4 and the anti-opioid systems as well as some other excitatory molecules, receptors, channels, chemokines, pro-inflammatory cytokines or lipids. This review summarizes the intracellular and intercellular pathways involved in OIH and highlights some mechanisms that may be challenged to limit OIH in the future.
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Affiliation(s)
- Laurie-Anne Roeckel
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France; Université de Strasbourg, Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France
| | - Glenn-Marie Le Coz
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France
| | - Claire Gavériaux-Ruff
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France; Université de Strasbourg, Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France; Ecole Supérieure de Biotechnologie de Strasbourg, Université de Strasbourg, France
| | - Frédéric Simonin
- Biotechnologie et Signalisation Cellulaire, UMR 7242 CNRS, Université de Strasbourg, Illkirch, France.
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Activity-dependent dephosphorylation of paxillin contributed to nociceptive plasticity in spinal cord dorsal horn. Pain 2016; 157:652-665. [DOI: 10.1097/j.pain.0000000000000415] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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AMPA Receptor Phosphorylation and Synaptic Colocalization on Motor Neurons Drive Maladaptive Plasticity below Complete Spinal Cord Injury. eNeuro 2015; 2:eN-NWR-0091-15. [PMID: 26668821 PMCID: PMC4677690 DOI: 10.1523/eneuro.0091-15.2015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 10/05/2015] [Accepted: 10/05/2015] [Indexed: 12/22/2022] Open
Abstract
Clinical spinal cord injury (SCI) is accompanied by comorbid peripheral injury in 47% of patients. Human and animal modeling data have shown that painful peripheral injuries undermine long-term recovery of locomotion through unknown mechanisms. Peripheral nociceptive stimuli induce maladaptive synaptic plasticity in dorsal horn sensory systems through AMPA receptor (AMPAR) phosphorylation and trafficking to synapses. Here we test whether ventral horn motor neurons in rats demonstrate similar experience-dependent maladaptive plasticity below a complete SCI in vivo. Quantitative biochemistry demonstrated that intermittent nociceptive stimulation (INS) rapidly and selectively increases AMPAR subunit GluA1 serine 831 phosphorylation and localization to synapses in the injured spinal cord, while reducing synaptic GluA2. These changes predict motor dysfunction in the absence of cell death signaling, suggesting an opportunity for therapeutic reversal. Automated confocal time-course analysis of lumbar ventral horn motor neurons confirmed a time-dependent increase in synaptic GluA1 with concurrent decrease in synaptic GluA2. Optical fractionation of neuronal plasma membranes revealed GluA2 removal from extrasynaptic sites on motor neurons early after INS followed by removal from synapses 2 h later. As GluA2-lacking AMPARs are canonical calcium-permeable AMPARs (CP-AMPARs), their stimulus- and time-dependent insertion provides a therapeutic target for limiting calcium-dependent dynamic maladaptive plasticity after SCI. Confirming this, a selective CP-AMPAR antagonist protected against INS-induced maladaptive spinal plasticity, restoring adaptive motor responses on a sensorimotor spinal training task. These findings highlight the critical involvement of AMPARs in experience-dependent spinal cord plasticity after injury and provide a pharmacologically targetable synaptic mechanism by which early postinjury experience shapes motor plasticity.
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Martin M, Contreras-Hernández E, Béjar J, Esposito G, Chávez D, Glusman S, Cortés U, Rudomin P. A machine learning methodology for the selection and classification of spontaneous spinal cord dorsum potentials allows disclosure of structured (non-random) changes in neuronal connectivity induced by nociceptive stimulation. Front Neuroinform 2015; 9:21. [PMID: 26379540 PMCID: PMC4549562 DOI: 10.3389/fninf.2015.00021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 08/10/2015] [Indexed: 01/13/2023] Open
Abstract
Previous studies aimed to disclose the functional organization of the neuronal networks involved in the generation of the spontaneous cord dorsum potentials (CDPs) generated in the lumbosacral spinal segments used predetermined templates to select specific classes of spontaneous CDPs. Since this procedure was time consuming and required continuous supervision, it was limited to the analysis of two specific types of CDPs (negative CDPs and negative positive CDPs), thus excluding potentials that may reflect activation of other neuronal networks of presumed functional relevance. We now present a novel procedure based in machine learning that allows the efficient and unbiased selection of a variety of spontaneous CDPs with different shapes and amplitudes. The reliability and performance of the present method is evaluated by analyzing the effects on the probabilities of generation of different classes of spontaneous CDPs induced by the intradermic injection of small amounts of capsaicin in the anesthetized cat, a procedure known to induce a state of central sensitization leading to allodynia and hyperalgesia. The results obtained with the selection method presently described allowed detection of spontaneous CDPs with specific shapes and amplitudes that are assumed to represent the activation of functionally coupled sets of dorsal horn neurones that acquire different, structured configurations in response to nociceptive stimuli. These changes are considered as responses tending to adequate transmission of sensory information to specific functional requirements as part of homeostatic adjustments.
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Affiliation(s)
- Mario Martin
- Department of Computer Science, Universitat Politècnica de Catalunya. BarcelonaTech Catalonia, Spain
| | - Enrique Contreras-Hernández
- Department of Physiology, Biophysics and Neurosciences, Center for Research and Advanced Studies, National Polytechnic Institute Mexico City, Mexico
| | - Javier Béjar
- Department of Computer Science, Universitat Politècnica de Catalunya. BarcelonaTech Catalonia, Spain
| | - Gennaro Esposito
- Department of Computer Science, Universitat Politècnica de Catalunya. BarcelonaTech Catalonia, Spain
| | - Diógenes Chávez
- Department of Physiology, Biophysics and Neurosciences, Center for Research and Advanced Studies, National Polytechnic Institute Mexico City, Mexico
| | - Silvio Glusman
- Department of Physiology, Biophysics and Neurosciences, Center for Research and Advanced Studies, National Polytechnic Institute Mexico City, Mexico
| | - Ulises Cortés
- Department of Computer Science, Universitat Politècnica de Catalunya. BarcelonaTech Catalonia, Spain ; Barcelona Supercomputing Center Catalonia, Spain
| | - Pablo Rudomin
- Department of Physiology, Biophysics and Neurosciences, Center for Research and Advanced Studies, National Polytechnic Institute Mexico City, Mexico ; El Colegio Nacional Mexico City, Mexico
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36
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[Neuropathic pain. How to open the blackbox]. Schmerz 2015; 29:479-80, 482-5. [PMID: 26264897 DOI: 10.1007/s00482-015-0028-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
This article, without presuming to be comprehensive, gives a brief outline of the development of research on neuropathic pain in Germany. Current clinical research on this subject focusses on the validation of human models, patient phenotyping, mechanism-based classification and treatment as well as on molecular pathomechanisms. This clinical research is based to a large extent on the work of several internationally recognized basic researchers in the 1990s. In particular, findings from system physiology led to the analysis of clinical phenotypes and the underlying pathophysiology. In parallel, basic research achieved international top levels through the development of innovative methods. Close cooperation, building of consortia and European networking made major contributions to the success of this research.
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Abstract
Nociceptors and neurons in the central nervous system (CNS) that receive nociceptive input show remarkable plasticity in response to injury. This plasticity is thought to underlie the development of chronic pain states. Hence, further understanding of the molecular mechanisms driving and maintaining this plasticity has the potential to lead to novel therapeutic approaches for the treatment of chronic pain states. An important concept in pain plasticity is the presence and persistence of "hyperalgesic priming." This priming arises from an initial injury and results in a remarkable susceptibility to normally subthreshold noxious inputs causing a prolonged pain state in primed animals. Here we describe our current understanding of how this priming is manifested through changes in signaling in the primary nociceptor as well as through memory like alterations at CNS synapses. Moreover, we discuss how commonly utilized analgesics, such as opioids, enhance priming therefore potentially contributing to the development of persistent pain states. Finally we highlight where these priming models draw parallels to common human chronic pain conditions. Collectively, these advances in our understanding of pain plasticity reveal a variety of targets for therapeutic intervention with the potential to reverse rather than palliate chronic pain states.
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Affiliation(s)
- Ram Kandasamy
- Department of Pharmacology, The University of Arizona, Tucson, AZ, 85721, USA
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38
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Spinal dopaminergic projections control the transition to pathological pain plasticity via a D1/D5-mediated mechanism. J Neurosci 2015; 35:6307-17. [PMID: 25904784 DOI: 10.1523/jneurosci.3481-14.2015] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The mechanisms that lead to the maintenance of chronic pain states are poorly understood, but their elucidation could lead to new insights into how pain becomes chronic and how it can potentially be reversed. We investigated the role of spinal dorsal horn neurons and descending circuitry in plasticity mediating a transition to pathological pain plasticity suggesting the presence of a chronic pain state using hyperalgesic priming. We found that when dorsal horn neurokinin 1 receptor-positive neurons or descending serotonergic neurons were ablated before hyperalgesic priming, IL-6- and carrageenan-induced mechanical hypersensitivity was impaired, and subsequent prostaglandin E2 (PGE2) response was blunted. However, when these neurons were lesioned after the induction of priming, they had no effect on the PGE2 response, reflecting differential mechanisms driving plasticity in a primed state. In stark contrast, animals with a spinally applied dopaminergic lesion showed intact IL-6- and carrageenan-induced mechanical hypersensitivity, but the subsequent PGE2 injection failed to cause mechanical hypersensitivity. Moreover, ablating spinally projecting dopaminergic neurons after the resolution of the IL-6- or carrageenan-induced response also reversed the maintenance of priming as assessed through mechanical hypersensitivity and the mouse grimace scale. Pharmacological antagonism of spinal dopamine D1/D5 receptors reversed priming, whereas D1/D5 agonists induced mechanical hypersensitivity exclusively in primed mice. Strikingly, engagement of D1/D5 coupled with anisomycin in primed animals reversed a chronic pain state, consistent with reconsolidation-like effects in the spinal dorsal horn. These findings demonstrate a novel role for descending dopaminergic neurons in the maintenance of pathological pain plasticity.
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39
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Beta-adrenergic antagonists during general anesthesia reduced postoperative pain: a systematic review and a meta-analysis of randomized controlled trials. J Anesth 2015; 29:934-43. [DOI: 10.1007/s00540-015-2041-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 06/21/2015] [Indexed: 12/11/2022]
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40
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Reconsolidation and the regulation of plasticity: moving beyond memory. Trends Neurosci 2015; 38:336-44. [PMID: 25987442 DOI: 10.1016/j.tins.2015.04.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 04/20/2015] [Accepted: 04/21/2015] [Indexed: 01/31/2023]
Abstract
Memory reconsolidation is a protein synthesis-dependent process that preserves, in some form, memories that have been destabilized through recall. Reconsolidation is a nearly universal phenomenon, occurring in a diverse array of species and learning tasks. The function of reconsolidation remains unclear but it has been proposed as a mechanism for updating or strengthening memories. Observations of an analog of reconsolidation in vitro and in sensory systems indicate that reconsolidation is unlikely to be a learning-specific phenomenon and may serve a broader function. We propose that reconsolidation arises from the activity-dependent induction of two coincident but opposing processes: the depotentiation and repotentiation of strengthened synapses. These processes suggest that reconsolidation reflects a fundamental mechanism that regulates and preserves synaptic strength.
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41
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Clark AK, Gruber-Schoffnegger D, Drdla-Schutting R, Gerhold KJ, Malcangio M, Sandkühler J. Selective activation of microglia facilitates synaptic strength. J Neurosci 2015; 35:4552-70. [PMID: 25788673 PMCID: PMC4363384 DOI: 10.1523/jneurosci.2061-14.2015] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 01/13/2015] [Accepted: 01/22/2015] [Indexed: 12/26/2022] Open
Abstract
Synaptic plasticity is thought to be initiated by neurons only, with the prevailing view assigning glial cells mere specify supportive functions for synaptic transmission and plasticity. We now demonstrate that glial cells can control synaptic strength independent of neuronal activity. Here we show that selective activation of microglia in the rat is sufficient to rapidly facilitate synaptic strength between primary afferent C-fibers and lamina I neurons, the first synaptic relay in the nociceptive pathway. Specifically, the activation of the CX3CR1 receptor by fractalkine induces the release of interleukin-1β from microglia, which modulates NMDA signaling in postsynaptic neurons, leading to the release of an eicosanoid messenger, which ultimately enhances presynaptic neurotransmitter release. In contrast to the conventional view, this form of plasticity does not require enhanced neuronal activity to trigger the events leading to synaptic facilitation. Augmentation of synaptic strength in nociceptive pathways represents a cellular model of pain amplification. The present data thus suggest that, under chronic pain states, CX3CR1-mediated activation of microglia drives the facilitation of excitatory synaptic transmission in the dorsal horn, which contributes to pain hypersensitivity in chronic pain states.
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Affiliation(s)
- Anna K Clark
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, A-1090 Vienna, Austria, and Wolfson Centre for Age Related Diseases, King's College London, London SE1 1UL, United Kingdom
| | - Doris Gruber-Schoffnegger
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, A-1090 Vienna, Austria, and
| | - Ruth Drdla-Schutting
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, A-1090 Vienna, Austria, and
| | - Katharina J Gerhold
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, A-1090 Vienna, Austria, and
| | - Marzia Malcangio
- Wolfson Centre for Age Related Diseases, King's College London, London SE1 1UL, United Kingdom
| | - Jürgen Sandkühler
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, A-1090 Vienna, Austria, and
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Price TJ, Inyang KE. Commonalities between pain and memory mechanisms and their meaning for understanding chronic pain. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 131:409-34. [PMID: 25744681 DOI: 10.1016/bs.pmbts.2014.11.010] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Pain sensing neurons in the periphery (called nociceptors) and the central neurons that receive their projections show remarkable plasticity following injury. This plasticity results in amplification of pain signaling that is now understood to be crucial for the recovery and survival of organisms following injury. These same plasticity mechanisms may drive a transition to a nonadaptive chronic pain state if they fail to resolve following the termination of the healing process. Remarkable advances have been achieved in the past two decades in understanding the molecular mechanisms that underlie pain plasticity following injury. The mechanisms bear a striking resemblance to molecular mechanisms involved in learning and memory processes in other brain regions, including the hippocampus and cerebral cortex. Here those mechanisms, their commonalities and subtle differences, will be highlighted and their role in causing chronic pain will be discussed. Arising from these data is the striking argument that chronic pain is a disease of the nervous system, which distinguishes this phenomena from acute pain that is frequently a symptom alerting the organism to injury. This argument has important implications for the development of disease modifying therapeutics.
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Affiliation(s)
- Theodore J Price
- Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, Texas, USA.
| | - Kufreobong E Inyang
- Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, Texas, USA
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43
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VGluT3⁺ primary afferents play distinct roles in mechanical and cold hypersensitivity depending on pain etiology. J Neurosci 2014; 34:12015-28. [PMID: 25186747 DOI: 10.1523/jneurosci.2157-14.2014] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Sensory nerve fibers differ not only with respect to their sensory modalities and conduction velocities, but also in their relative roles for pain hypersensitivity. It is presently largely unknown which types of sensory afferents contribute to various forms of neuropathic and inflammatory pain hypersensitivity. Vesicular glutamate transporter 3-positive (VGluT3(+)) primary afferents, for example, have been implicated in mechanical hypersensitivity after inflammation, but their role in neuropathic pain remains under debate. Here, we investigated a possible etiology-dependent contribution of VGluT3(+) fibers to mechanical and cold hypersensitivity in different models of inflammatory and neuropathic pain. In addition to VGluT3(-/-) mice, we used VGluT3-channelrhodopsin 2 mice to selectively stimulate VGluT3(+) sensory afferents by blue light, and to assess light-evoked behavior in freely moving mice. We show that VGluT3(-/-) mice develop reduced mechanical hypersensitivity upon carrageenan injection. Both mechanical and cold hypersensitivity were reduced in VGluT3(-/-) mice in neuropathic pain evoked by the chemotherapeutic oxaliplatin, but not in the chronic constriction injury (CCI) model of the sciatic nerve. Further, we provide direct evidence that, despite not mediating painful stimuli in naive mice, activation of VGluT3(+) sensory fibers by light elicits pain behavior in the oxaliplatin but not the CCI model. Immunohistochemical and electrophysiological data support a role of transient receptor potential melastatin 8-mediated facilitation of synaptic strength at the level of the dorsal horn as an underlying mechanism. Together, we demonstrate that VGluT3(+) fibers contribute in an etiology-dependent manner to the development of mechano-cold hypersensitivity.
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44
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Li YZ, Tang XH, Wang CY, Hu N, Xie KL, Wang HY, Yu YH, Wang GL. Glycogen Synthase Kinase-3β Inhibition Prevents Remifentanil-Induced Postoperative Hyperalgesia via Regulating the Expression and Function of AMPA Receptors. Anesth Analg 2014; 119:978-987. [DOI: 10.1213/ane.0000000000000365] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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45
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Caspani O, Reitz MC, Ceci A, Kremer A, Treede RD. Tramadol reduces anxiety-related and depression-associated behaviors presumably induced by pain in the chronic constriction injury model of neuropathic pain in rats. Pharmacol Biochem Behav 2014; 124:290-6. [DOI: 10.1016/j.pbb.2014.06.018] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2013] [Revised: 05/22/2014] [Accepted: 06/20/2014] [Indexed: 01/01/2023]
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46
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47
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A spinal analog of memory reconsolidation enables reversal of hyperalgesia. Nat Neurosci 2014; 17:1043-5. [PMID: 24997764 PMCID: PMC4978538 DOI: 10.1038/nn.3758] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 06/06/2014] [Indexed: 01/21/2023]
Abstract
Hyperalgesia arising from sensitization of pain relays in the spinal dorsal horn shares many mechanistic and phenotypic parallels with memory formation. We discover that mechanical hyperalgesia can be rendered labile and reversible in mice after reactivation of spinal pain pathways in a process analogous to memory reconsolidation. These findings reveal a novel regulatory mechanism underlying hyperalgesia and demonstrate the existence of reconsolidation-like processes in a sensory system.
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48
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Luo C, Kuner T, Kuner R. Synaptic plasticity in pathological pain. Trends Neurosci 2014; 37:343-55. [DOI: 10.1016/j.tins.2014.04.002] [Citation(s) in RCA: 126] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 03/31/2014] [Accepted: 04/09/2014] [Indexed: 02/06/2023]
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49
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Zhang YL, Ou P, Lu XH, Chen YP, Xu JM, Dai RP. Effect of intraoperative high-dose remifentanil on postoperative pain: a prospective, double blind, randomized clinical trial. PLoS One 2014; 9:e91454. [PMID: 24667391 PMCID: PMC3965388 DOI: 10.1371/journal.pone.0091454] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 02/10/2014] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Remifentanil, an ultra-short-acting opioid, is widely used for pain control during surgery. However, regular dose (RD) remifentanil exacerbates postoperative pain in a dose-dependent manner. Recent studies suggest that high-dose (HD) remifentanil offers sustained analgesia in experimental studies. We thus hypothesized that intraoperative administration of high-dose remifentanil may attenuate postoperative pain. METHODS In this prospective, randomized, double blind, controlled clinical study, sixty patients undergoing thyroidectomy (18-60 years-of-age) received an intraoperative infusion of 0.2 (RD group) or 1.2 μg kg(-1) min(-1) (HD group) remifentanil during thyroidectomy. A visual analogue scale (VAS) was used to measure pain intensity. Mechanical pain threshold on the forearm was assessed using von Frey filaments before surgery (baseline), 2 h postoperatively and 18-24 h postoperatively. The primary outcome was to compare the difference of VAS score at different time points after operation and morphine consumption 24 h postoperatively between RD and HD groups. The second outcome was to compare the difference of mechanical pain thresholds in the forearm postoperatively between RD and the HD groups. RESULTS VAS scores were lower 30 min postoperatively in the HD group (1.29 ± 1.67, 95% CI 0.64-1.94) compared with the RD group (2.21 ± 1.67, 95% CI 1.57-2.84) (t = 3.427, p = 0.0043, RD group vs. HD group). Postoperative morphine consumption was much lower in the HD group compared with the RD group (1.27 ± 1.88 mg vs. 0.35 ± 1.25 mg, p = 0.033). In both groups, mechanical pain threshold was decreased 18-24 h postoperatively (2.93 ± 0.209 Ln(g) vs. 3.454 ± 2.072 Ln(g), p = 0.032 in RD group; 2.910 ± 0.196 Ln(g) vs. 3.621 ± 0.198 Ln(g), p = 0.006 in HD group, 18-24 h postoperatively vs baseline). CONCLUSIONS Intraoperative administration of high-dose remifentanil decreased VAS scores and morphine consumption postoperatively. Thus, modulation of intraoperative opiates may be a simple and effective method of postoperative pain management. TRIAL REGISTRATION This trial is registered in ClinicalTrials.gov, with the Name: Effect of Higher Doses of Remifentanil on Postoperative Pain in Patients Undergoing Thyroidectomy, and ID number: NCT01761149.
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Affiliation(s)
- Yan-Ling Zhang
- Department of Anesthesiology, The Second Xiangya Hospital of Central South University, Changsha, Hunan Province, China
| | - Peng Ou
- Department of Anesthesiology, The Second Xiangya Hospital of Central South University, Changsha, Hunan Province, China
| | - Xiang-Hang Lu
- Department of Anesthesiology, The Second Xiangya Hospital of Central South University, Changsha, Hunan Province, China
| | - Yan-Ping Chen
- Department of Anesthesiology, The Second Xiangya Hospital of Central South University, Changsha, Hunan Province, China
| | - Jun-Mei Xu
- Department of Anesthesiology, The Second Xiangya Hospital of Central South University, Changsha, Hunan Province, China
| | - Ru-Ping Dai
- Department of Anesthesiology, The Second Xiangya Hospital of Central South University, Changsha, Hunan Province, China
- * E-mail:
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50
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Atwood BK, Kupferschmidt DA, Lovinger DM. Opioids induce dissociable forms of long-term depression of excitatory inputs to the dorsal striatum. Nat Neurosci 2014; 17:540-8. [PMID: 24561996 DOI: 10.1038/nn.3652] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 01/20/2014] [Indexed: 11/09/2022]
Abstract
As prescription opioid analgesic abuse rates rise, so does the need to understand the long-term effects of opioid exposure on brain function. The dorsal striatum is an important site for drug-induced neuronal plasticity. We found that exogenously applied and endogenously released opioids induced long-term depression (OP-LTD) of excitatory inputs to the dorsal striatum in mice and rats. Mu and delta OP-LTD, although both being presynaptically expressed, were dissociable in that they summated, differentially occluded endocannabinoid-LTD and inhibited different striatal inputs. Kappa OP-LTD showed a unique subregional expression in striatum. A single in vivo exposure to the opioid analgesic oxycodone disrupted mu OP-LTD and endocannabinoid-LTD, but not delta or kappa OP-LTD. These data reveal previously unknown opioid-mediated forms of long-term striatal plasticity that are differentially affected by opioid analgesic exposure and are likely important mediators of striatum-dependent learning and behavior.
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Affiliation(s)
- Brady K Atwood
- Section on Synaptic Pharmacology, Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, US National Institutes of Health, Bethesda, Maryland, USA
| | - David A Kupferschmidt
- Section on Synaptic Pharmacology, Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, US National Institutes of Health, Bethesda, Maryland, USA
| | - David M Lovinger
- Section on Synaptic Pharmacology, Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, US National Institutes of Health, Bethesda, Maryland, USA
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