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Zhang Z, Zheng H, Yu Q, Jing X. Understanding of Spinal Wide Dynamic Range Neurons and Their Modulation on Pathological Pain. J Pain Res 2024; 17:441-457. [PMID: 38318328 PMCID: PMC10840524 DOI: 10.2147/jpr.s446803] [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: 10/26/2023] [Accepted: 01/12/2024] [Indexed: 02/07/2024] Open
Abstract
The spinal dorsal horn (SDH) transmits sensory information from the periphery to the brain. Wide dynamic range (WDR) neurons within this relay site play a critical role in modulating and integrating peripheral sensory inputs, as well as the process of central sensitization during pathological pain. This group of spinal multi-receptive neurons has attracted considerable attention in pain research due to their capabilities for encoding the location and intensity of nociception. Meanwhile, transmission, processing, and modulation of incoming afferent information in WDR neurons also establish the underlying basis for investigating the integration of acupuncture and pain signals. This review aims to provide a comprehensive examination of the distinctive features of WDR neurons and their involvement in pain. Specifically, we will examine the regulation of diverse supraspinal nuclei on these neurons and analyze their potential in elucidating the mechanisms of acupuncture analgesia.
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Affiliation(s)
- Zhiyun Zhang
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, People’s Republic of China
| | - Hao Zheng
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, People’s Republic of China
| | - Qingquan Yu
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, People’s Republic of China
| | - Xianghong Jing
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, People’s Republic of China
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2
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Pereira-Silva R, Serrão P, Lourença Neto F, Martins I. Diffuse noxious inhibitory controls in chronic joint inflammatory Pain: Study of the descending serotonergic modulation mediated through 5HT3 receptors. NEUROBIOLOGY OF PAIN (CAMBRIDGE, MASS.) 2023; 13:100123. [PMID: 36915290 PMCID: PMC10006856 DOI: 10.1016/j.ynpai.2023.100123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 02/27/2023] [Accepted: 02/27/2023] [Indexed: 03/05/2023]
Abstract
The loss of diffuse noxious inhibitory controls (DNIC) is recognized as a predictor of chronic pain. Mechanistically, DNIC produces analgesia by a heterotopically applied conditioning-noxious stimulus (CS) and yet underexplored descending modulatory inputs. Here, we aimed at studying DNIC in monoarthritis (MA) by exploring the spinal component of the descending serotonergic system, specifically 5-hydroxytryptamine 3 receptors (5-HT3R). MA was induced in male Wistar rats by tibiotarsal injection of complete Freund's adjuvant. Mechanical hyperalgesia and DNIC were assessed weekly by the Randall-Selitto test. Immunohistochemistry was used to quantify spinal 5-HT3R, and tryptophan hydroxylase (TPH) colocalization with phosphorylated extracellular signal-regulated protein kinases 1/2 at the rostroventromedial medulla (RVM). Spinal serotonin (5-HT) was quantified by HPLC. The effects of intrathecal ondansetron, a 5-HT3R antagonist, were assessed on mechanical hyperalgesia and DNIC. MA resulted in a prolonged steady-state mechanical hyperalgesia. In contrast, DNIC peaked after 28 days, decreasing afterwards until extinction at 42 days. At this later timepoint, MA rats showed increased: (i) spinal 5-HT3R and 5-HT levels, (ii) neuronal serotonergic activation and TPH expression at the RVM. Ondansetron reversed mechanical hyperalgesia and restored DNIC, regardless of being administered before or after CS. However, data variability was higher upon administration before CS in MA-animals. Prolonged MA upregulates the descending serotonergic modulation, which simultaneously results in increased nociception and DNIC extinction, through 5-HT3R. Our data suggest a role for spinal 5-HT3R in the top-down modulation of DNIC. Additionally, these receptors may also be involved in the bottom-up circuitry implicated in the trigger of DNIC.
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Affiliation(s)
- Raquel Pereira-Silva
- Instituto de Investigação e Inovação em Saúde da Universidade do Porto (I3S). Rua Alfredo Allen 208, 4200 393 Porto, Portugal.,Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto. Rua Alfredo Allen 208, 4200-393 Porto, Portugal.,Departamento de Biomedicina - Unidade de Biologia Experimental, Faculdade de Medicina, Universidade do Porto. Alameda Prof. Hernâni Monteiro 4200-319 Porto, Portugal
| | - Paula Serrão
- Departamento de Biomedicina - Unidade de Farmacologia e Terapêutica, Faculdade de Medicina, Universidade do Porto. Alameda Prof. Hernâni Monteiro 4200-319 Porto, Portugal.,MedInUP - Center for Drug Discovery and Innovative Medicines, University of Porto. Alameda Prof. Hernâni Monteiro 4200-319 Porto, Portugal
| | - Fani Lourença Neto
- Instituto de Investigação e Inovação em Saúde da Universidade do Porto (I3S). Rua Alfredo Allen 208, 4200 393 Porto, Portugal.,Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto. Rua Alfredo Allen 208, 4200-393 Porto, Portugal.,Departamento de Biomedicina - Unidade de Biologia Experimental, Faculdade de Medicina, Universidade do Porto. Alameda Prof. Hernâni Monteiro 4200-319 Porto, Portugal
| | - Isabel Martins
- Instituto de Investigação e Inovação em Saúde da Universidade do Porto (I3S). Rua Alfredo Allen 208, 4200 393 Porto, Portugal.,Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto. Rua Alfredo Allen 208, 4200-393 Porto, Portugal.,Departamento de Biomedicina - Unidade de Biologia Experimental, Faculdade de Medicina, Universidade do Porto. Alameda Prof. Hernâni Monteiro 4200-319 Porto, Portugal
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Yu Q, Cao W, Wang X, He W, Sun X, Chen L, Su Y, Zhang Z, Jing X. The Effect of Pre-Electroacupuncture on Nociceptive Discharges of Spinal Wide Dynamic Range Neurons in Rat. J Pain Res 2023; 16:695-706. [PMID: 36915279 PMCID: PMC10007980 DOI: 10.2147/jpr.s396481] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 02/21/2023] [Indexed: 03/09/2023] Open
Abstract
Purpose Spinal wide dynamic range (WDR) neurons are well studied in pain models and they play critical roles in regulating nociception. Evidence has started to accumulate that acupuncture produces a good analgesic effect via activating different primary fibers with distinct intensities. The purpose of the present study was to compare the distinct intensities of pre-electroacupuncture (pre-EA) at local muscular receptive fields (RFs), adjacent or contralateral non-RFs regulating the nociceptive discharges of spinal WDR neurons evoked by hypertonic saline (HS). Materials and Methods Spinal segments of electrophysiological recording were identified by neural tracers applied at the left gastrocnemius muscle. The thresholds of Aβ (TAβ), Aδ (TAδ) and C (TC) components of WDR neurons were measured to determine the intensity of pre-EA by extracellular recording. The discharges of WDR neurons induced by distinct intensities of pre-EA and 200 µL HS (6%) injection in left gastrocnemius muscle of rats were observed by extracellular recording. Results The spinal segments of WDR neurons were confirmed in lumbar (L)5-6 area according to the projective segments of dorsal root ganglion. TAβ, TAδ and TC of WDR neurons was determined to be 0.5, 1, and 2 mA, respectively. The pre-EA with intensities of TAβ (P < 0.05), TAδ (P < 0.05), TC (P < 0.05) or 2TC (P < 0.01) at ipsilateral adjacent non-RFs significantly reduced the discharges of WDR neurons, while at local RFs only pre-EA of TAδ (P < 0.05), TC (P < 0.05) and 2TC (P < 0.01) could inhibit the nociceptive discharges. In addition, intensity of pre-EA at contralateral non-RFs should reach at least TC to effectively inhibit the firing rates of WDR neurons (P < 0.01). Conclusion Pre-EA could suppress nociceptive discharges of WDR neurons and the inhibitory effects were dependent on the distinct intensities and locations of stimulation.
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Affiliation(s)
- Qingquan Yu
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, People's Republic of China
| | - Wanying Cao
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, People's Republic of China
| | - Xiaoyu Wang
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, People's Republic of China
| | - Wei He
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, People's Republic of China
| | - Xiaoyue Sun
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, People's Republic of China
| | - Lizhen Chen
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, People's Republic of China
| | - Yangshuai Su
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, People's Republic of China
| | - Zhiyun Zhang
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, People's Republic of China
| | - Xianghong Jing
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, People's Republic of China
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Chen Q, Heinricher MM. Shifting the Balance: How Top-Down and Bottom-Up Input Modulate Pain via the Rostral Ventromedial Medulla. FRONTIERS IN PAIN RESEARCH 2022; 3:932476. [PMID: 35836737 PMCID: PMC9274196 DOI: 10.3389/fpain.2022.932476] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 05/23/2022] [Indexed: 11/17/2022] Open
Abstract
The sensory experience of pain depends not only on the transmission of noxious information (nociception), but on the state of the body in a biological, psychological, and social milieu. A brainstem pain-modulating system with its output node in the rostral ventromedial medulla (RVM) can regulate the threshold and gain for nociceptive transmission. This review considers the current understanding of how RVM pain-modulating neurons, namely ON-cells and OFF-cells, are engaged by “top-down” cognitive and emotional factors, as well as by “bottom-up” sensory inputs, to enhance or suppress pain.
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Affiliation(s)
- Qiliang Chen
- Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University, Stanford, CA, United States
| | - Mary M. Heinricher
- Department of Neurological Surgery and Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
- *Correspondence: Mary M. Heinricher
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Liu L, Xu XB, Qu ZY, Zhao LP, Zhang CS, Li ZJ, Lyu TL, Wang XF, Jing XH, Li B. Determining 5HT 7R's Involvement in Modifying the Antihyperalgesic Effects of Electroacupuncture on Rats With Recurrent Migraine. Front Neurosci 2021; 15:668616. [PMID: 34163324 PMCID: PMC8215279 DOI: 10.3389/fnins.2021.668616] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 04/20/2021] [Indexed: 01/14/2023] Open
Abstract
Electroacupuncture (EA) is widely used in clinical practice to relieve migraine pain. 5-HT7 receptor (5-HT7R) has been reported to play an excitatory role in neuronal systems and regulate hyperalgesic pain and neurogenic inflammation. 5-HT7R could influence phosphorylation of protein kinase A (PKA)- or extracellular signal-regulated kinase1 / 2 (ERK1 / 2)-mediated signaling pathways, which mediate sensitization of nociceptive neurons via interacting with cyclic adenosine monophosphate (cAMP). In this study, we evaluated the role of 5-HT7R in the antihyperalgesic effects of EA and the underlying mechanism through regulation of PKA and ERK1 / 2 in trigeminal ganglion (TG) and trigeminal nucleus caudalis (TNC). Hyperalgesia was induced in rats with dural injection of inflammatory soup (IS) to cause meningeal neurogenic inflammatory pain. Electroacupuncture was applied for 15 min every other day before IS injection. Von Frey filaments, tail-flick, hot-plate, and cold-plated tests were used to evaluate the mechanical and thermal hyperalgesia. Neuronal hyperexcitability in TNC was studied by an electrophysiological technique. The 5-HT7R antagonist (SB269970) or 5-HT7R agonist (AS19) was administered intrathecally before each IS application at 2-day intervals during the 7-day injection protocol. The changes in 5-HT7R and 5-HT7R-associated signaling pathway were examined by real-time polymerase chain reaction (RT-PCR), Western blot, immunofluorescence, and enzyme-linked immunosorbent assay (ELISA) analyses. When compared with IS group, mechanical and thermal pain thresholds of the IS + EA group were significantly increased. Furthermore, EA prevented the enhancement of both spontaneous activity and evoked responses of second-order trigeminovascular neurons in TNC. Remarkable decreases in 5-HT7R mRNA expression and protein levels were detected in the IS + EA group. More importantly, 5-HT7R agonist AS19 impaired the antihyperalgesic effects of EA on p-PKA and p-ERK1 / 2. Injecting 5-HT7R antagonist SB-269970 into the intrathecal space of IS rats mimicked the effects of EA antihyperalgesia and inhibited p-PKA and p-ERK1 / 2. Our findings indicate that 5-HT7R mediates the antihyperalgesic effects of EA on IS-induced migraine pain by regulating PKA and ERK1 / 2 in TG and TNC.
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Affiliation(s)
- Lu Liu
- Department of Acupuncture and Moxibustion, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing Key Laboratory of Acupuncture Neuromodulation, Beijing, China
| | - Xiao-Bai Xu
- Department of Acupuncture and Moxibustion, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing Key Laboratory of Acupuncture Neuromodulation, Beijing, China
| | - Zheng-Yang Qu
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
| | - Luo-Peng Zhao
- Department of Acupuncture and Moxibustion, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing Key Laboratory of Acupuncture Neuromodulation, Beijing, China.,Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing Institute of Traditional Chinese Medicine, Beijing, China
| | - Claire-Shuiqing Zhang
- School of Health and Biomedical Sciences, RMIT University, Melbourne, VIC, Australia
| | - Zhi-Juan Li
- Department of Acupuncture and Moxibustion, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing Key Laboratory of Acupuncture Neuromodulation, Beijing, China
| | - Tian-Li Lyu
- Department of Acupuncture and Moxibustion, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing Key Laboratory of Acupuncture Neuromodulation, Beijing, China
| | - Xue-Fei Wang
- Department of Acupuncture and Moxibustion, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing Key Laboratory of Acupuncture Neuromodulation, Beijing, China
| | - Xiang-Hong Jing
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
| | - Bin Li
- Department of Acupuncture and Moxibustion, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing Key Laboratory of Acupuncture Neuromodulation, Beijing, China
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6
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Kucharczyk MW, Valiente D, Bannister K. Developments in Understanding Diffuse Noxious Inhibitory Controls: Pharmacological Evidence from Pre-Clinical Research. J Pain Res 2021; 14:1083-1095. [PMID: 33907456 PMCID: PMC8068490 DOI: 10.2147/jpr.s258602] [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] [Received: 02/12/2021] [Accepted: 04/06/2021] [Indexed: 12/21/2022] Open
Abstract
Bulbospinal pathways regulate nociceptive processing, and inhibitory modulation of nociception can be achieved via the activity of diffuse noxious inhibitory controls (DNIC), a unique descending pathway activated upon application of a conditioning stimulus (CS). Numerous studies have investigated the effects of varied pharmacological systems on the expression status of a) DNIC (as measured in anaesthetised animals) and b) the descending control of nociception (DCN), a surrogate measure of DNIC-like effects in conscious animals. However, the complexity of the underlying circuitry that governs initiation of a top-down inhibitory response in reaction to a CS, coupled with the methodological limitations associated with using pharmacological tools for its study, has often obscured the exact role(s) of a given drug. In this literature review, we discuss the pharmacological manipulation interrogation strategies that have hitherto been used to examine the functionality of DNIC and DCN. Discreet administration of a substance in the spinal cord or brain is considered in the context of action on one of four hypothetical systems that underlie the functionality of DNIC/DCN, where interpreting the outcome is often complicated by overlapping qualities. Systemic pharmacological modulation of DNIC/DCN is also discussed despite the fact that the precise location of drug action(s) cannot be pinpointed. Chiefly, modulation of the noradrenergic, serotonergic and opioidergic transmission systems impacts DNIC/DCN in a manner that relates to drug class, route of administration and health/disease state implicated. The advent of increasingly sophisticated interrogation tools will expedite our full understanding of the circuitries that modulate naturally occurring pain-inhibiting pathways.
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Affiliation(s)
- Mateusz Wojciech Kucharczyk
- Central Modulation of Pain Group, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, SE1 1UL., UK
| | - Diego Valiente
- Central Modulation of Pain Group, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, SE1 1UL., UK
| | - Kirsty Bannister
- Central Modulation of Pain Group, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, SE1 1UL., UK
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7
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Wang S, Wang J, Liu K, Bai W, Cui X, Han S, Gao X, Zhu B. Signaling Interaction between Facial and Meningeal Inputs of the Trigeminal System Mediates Peripheral Neurostimulation Analgesia in a Rat Model of Migraine. Neuroscience 2020; 433:184-199. [PMID: 32171818 DOI: 10.1016/j.neuroscience.2020.03.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Revised: 02/25/2020] [Accepted: 03/03/2020] [Indexed: 01/17/2023]
Abstract
Peripheral neurostimulation within the trigeminal nerve territory has been used for pain alleviation during migraine attacks, but the mechanistic basis of this non-invasive intervention is still poorly understood. In this study, we investigated the therapeutic role of peripheral stimulation of the trigeminal nerve, which provides homosegmental innervation to intracranial structures, by assessing analgesic effects in a nitroglycerin (NTG)-induced rat model of migraine. As a result of neurogenic inflammatory responses in the trigeminal nervous system, plasma protein extravasation was induced in facial skin by applying noxious stimulation to the dura mater. Noxious chemical stimulation of the dura mater led to protein extravasation in facial cutaneous tissues and caused mechanical sensitivity. Trigeminal ganglion (TG) neurons were double-labeled via retrograde tracing to detect bifurcated axons. Extracellular recordings of wide dynamic range (WDR) neurons in the spinal trigeminal nucleus caudalis (Sp5C) demonstrated the convergence and interaction of inputs from facial tissues and the dura mater. Peripheral neurostimulation of homotopic facial tissues represented segmental pain inhibition on cephalic cutaneous allodynia in the migraine model. The results indicated that facial territories and intracranial structures were directly connected with each other through bifurcated double-labeled neurons in the TG and through second-order WDR neurons. Homotopic stimulation at the C-fiber intensity threshold resulted in much stronger inhibition of analgesia than the same intensity of heterotopic stimulation. These results provide novel evidence for the neurological bases through which peripheral neurostimulation may be effective in treating migraine in clinical practice.
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Affiliation(s)
- Shuya Wang
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
| | - Jia Wang
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
| | - Kun Liu
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
| | - Wanzhu Bai
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
| | - Xiang Cui
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
| | - Shu Han
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
| | - Xinyan Gao
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China.
| | - Bing Zhu
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China.
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8
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Patel R, Dickenson AH. A study of cortical and brainstem mechanisms of diffuse noxious inhibitory controls in anaesthetised normal and neuropathic rats. Eur J Neurosci 2019; 51:952-962. [PMID: 31518451 PMCID: PMC7079135 DOI: 10.1111/ejn.14576] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 08/26/2019] [Accepted: 09/03/2019] [Indexed: 12/30/2022]
Abstract
Diffuse noxious inhibitory controls (DNIC) are a mechanism of endogenous descending pain modulation and are deficient in a large proportion of chronic pain patients. However, the pathways involved remain only partially determined with several cortical and brainstem structures implicated. This study examined the role of the dorsal reticular nucleus (DRt) and infralimbic (ILC) region of the medial prefrontal cortex in DNIC. In vivo electrophysiology was performed to record from dorsal horn lamina V/VI wide dynamic range neurones with left hind paw receptive fields in anaesthetised sham‐operated and L5/L6 spinal nerve‐ligated (SNL) rats. Evoked neuronal responses were quantified in the presence and absence of a conditioning stimulus (left ear clamp). In sham rats, DNIC were reproducibly recruited by a heterotopically applied conditioning stimulus, an effect that was absent in neuropathic rats. Intra‐DRt naloxone had no effect on spinal neuronal responses to dynamic brush, punctate mechanical, evaporative cooling and heat stimuli in sham and SNL rats. In addition, intra‐DRt naloxone blocked DNIC in sham rats, but had no effect in SNL rats. Intra‐ILC lidocaine had no effect on spinal neuronal responses to dynamic brush, punctate mechanical, evaporative cooling and heat stimuli in sham and SNL rats. However, differential effects were observed in relation to the expression of DNIC; intra‐ILC lidocaine blocked activation of DNIC in sham rats but restored DNIC in SNL rats. These data suggest that the ILC is not directly involved in mediating DNIC but can modulate its activation and that DRt involvement in DNIC requires opioidergic signalling.
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Affiliation(s)
- Ryan Patel
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK
| | - Anthony H Dickenson
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK
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10
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Torta DM, Jure FA, Andersen OK, Biurrun Manresa JA. Intense and sustained pain reduces cortical responses to auditory stimuli: Implications for the interpretation of the effects of heterotopic noxious conditioning stimulation in humans. Eur J Neurosci 2019; 50:3934-3943. [DOI: 10.1111/ejn.14546] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 07/24/2019] [Accepted: 08/06/2019] [Indexed: 12/15/2022]
Affiliation(s)
- Diana M. Torta
- Health Psychology Faculty of Psychology and Educational Sciences KU Leuven Leuven Belgium
- Institute of Neuroscience UC Louvain Brussels Belgium
| | - Fabricio A. Jure
- Center for Neuroplasticity and Pain SMI® Department of Health Science and Technology Aalborg University Aalborg Denmark
| | - Ole K. Andersen
- Center for Neuroplasticity and Pain SMI® Department of Health Science and Technology Aalborg University Aalborg Denmark
| | - José A.B. Biurrun Manresa
- Center for Neuroplasticity and Pain SMI® Department of Health Science and Technology Aalborg University Aalborg Denmark
- Institute for Research and Development in Bioengineering and Bioinformatics (IBB) CONICET‐UNER Entre Ríos Argentina
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11
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Acquisition of analgesic properties by the cholecystokinin (CCK)/CCK2 receptor system within the amygdala in a persistent inflammatory pain condition. Pain 2019; 160:345-357. [PMID: 30281531 DOI: 10.1097/j.pain.0000000000001408] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Pain is associated with negative emotions such as anxiety, but the underlying neurocircuitry and modulators of the association of pain and anxiety remain unclear. The neuropeptide cholecystokinin (CCK) has both pronociceptive and anxiogenic properties, so we explored the role of CCK in anxiety and nociception in the central amygdala (CeA), a key area in control of emotions and descending pain pathways. Local infusion of CCK into the CeA of control rats increased anxiety, as measured in the light-dark box test, but had no effect on mechanical sensitivity. By contrast, intra-CeA CCK infusion 4 days after Complete Freund's Adjuvant (CFA) injection into the hindpaw resulted in analgesia, but also in loss of its anxiogenic capacity. Inflammatory conditions induced changes in the CeA CCK signaling system with an increase of CCK immunoreactivity and a decrease in CCK1, but not CCK2, receptor mRNA. In CFA rats, patch-clamp experiments revealed that CCK infusion increased CeA neuron excitability. It also partially blocked the discharge of wide dynamic range neurons in the dorsal spinal cord. These effects of CCK on CeA and spinal neurons in CFA rats were mimicked by the specific CCK2 receptor agonist, gastrin. This analgesic effect was likely mediated by identified CeA neurons projecting to the periaqueductal gray matter that express CCK receptors. Together, our data demonstrate that intra-CeA CCK infusion activated a descending CCK2 receptor-dependent pathway that inhibited spinal neuron discharge. Thus, persistent pain induces a functional switch to a newly identified analgesic capacity of CCK in the amygdala, indicating central emotion-related circuit controls pain transmission in spinal cord.
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12
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Lv ZT, Shen LL, Zhu B, Zhang ZQ, Ma CY, Huang GF, Yin J, Yu LL, Yu SY, Ding MQ, Li J, Yuan XC, He W, Jing XH, Li M. Effects of intensity of electroacupuncture on chronic pain in patients with knee osteoarthritis: a randomized controlled trial. Arthritis Res Ther 2019; 21:120. [PMID: 31088511 PMCID: PMC6518678 DOI: 10.1186/s13075-019-1899-6] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 04/17/2019] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Conditioned pain modulation (CPM) is impaired in people with chronic pain such as knee osteoarthritis (KOA). The purpose of this randomized, controlled clinical trial was to investigate whether strong electroacupuncture (EA) was more effective on chronic pain by strengthening the CPM function than weak EA or sham EA in patients with KOA. METHODS In this multicenter, three-arm parallel, single-blind randomized controlled trial, 301 patients with KOA were randomly assigned. Patients were randomized into three groups based on EA current intensity: strong EA (> 2 mA), weak EA (< 0.5 mA), and sham EA (non-acupoint). Treatments consisted of five sessions per week, for 2 weeks. Primary outcome measures were visual analog scale (VAS), CPM function, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). RESULTS Three hundred one patients with KOA were randomly assigned, among which 271 (90.0%) completed the study (mean age 63.93 years old). One week of EA had a clinically important improvement in VAS and WOMAC but not in CPM function. After 2 weeks treatment, EA improved VAS, CPM, and WOMAC compared with baseline. Compared with sham EA, weak EA (3.8; 95% CI 3.45, 4.15; P < .01) and strong EA (13.54; 95% CI 13.23, 13.85; P < .01) were better in improving CPM function. Compared with weak EA, strong EA was better in enhancing CPM function (9.73; 95% CI 9.44, 10.02; P < .01), as well as in reducing VAS and total WOMAC score. CONCLUSION EA should be administered for at least 2 weeks to exert a clinically important effect on improving CPM function of KOA patients. Strong EA is better than weak or sham EA in alleviating pain intensity and inhibiting chronic pain. TRIAL REGISTRATION This study was registered with the Chinese Clinical Trial Registry ( ChiCTR-ICR-14005411 ), registered on 31 October 2014.
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Affiliation(s)
- Zheng-Tao Lv
- Department of Neurobiology, School of Basic Medicine, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, 430030, China.,Department of Orthopedics, Tongji Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Lin-Lin Shen
- Combined Traditional Chinese and Western Medicine Hospital affiliated to Tongji Medical College of Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Bing Zhu
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, 100700, China
| | | | | | - Guo-Fu Huang
- Combined Traditional Chinese and Western Medicine Hospital affiliated to Tongji Medical College of Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Jing Yin
- The Third Hospital of Wuhan, Wuhan, 430060, China
| | - Ling-Ling Yu
- Department of Neurobiology, School of Basic Medicine, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, 430030, China.,Combined Traditional Chinese and Western Medicine Hospital affiliated to Tongji Medical College of Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Si-Yi Yu
- School of Acupuncture and Moxibustion, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
| | | | - Jing Li
- Union Hospital affiliated to Tongji Medical College of Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Xiao-Cui Yuan
- Department of Neurobiology, School of Basic Medicine, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Wei He
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, 100700, China
| | - Xiang-Hong Jing
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, 100700, China.
| | - Man Li
- Department of Neurobiology, School of Basic Medicine, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, 430030, China.
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Gainfully employing descending controls in acute and chronic pain management. Vet J 2018; 237:16-25. [DOI: 10.1016/j.tvjl.2018.05.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 05/15/2018] [Accepted: 05/16/2018] [Indexed: 12/30/2022]
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Abstract
The rostral ventromedial medulla (RVM) has a well-documented role in pain modulation and exerts antinociceptive and pronociceptive influences mediated by 2 distinct classes of neurons, OFF-cells and ON-cells. OFF-cells are defined by a sudden pause in firing in response to nociceptive inputs, whereas ON-cells are characterized by a "burst" of activity. Although these reflex-related changes in ON- and OFF-cell firing are critical to their pain-modulating function, the pathways mediating these responses have not been identified. The present experiments were designed to test the hypothesis that nociceptive input to the RVM is relayed through the parabrachial complex (PB). In electrophysiological studies, ON- and OFF-cells were recorded in the RVM of lightly anesthetized male rats before and after an infusion of lidocaine or muscimol into PB. The ON-cell burst and OFF-cell pause evoked by noxious heat or mechanical probing were substantially attenuated by inactivation of the lateral, but not medial, parabrachial area. Retrograde tracing studies showed that neurons projecting to the RVM were scattered throughout PB. Few of these neurons expressed calcitonin gene-related peptide, suggesting that the RVM projection from PB is distinct from that to the amygdala. These data show that a substantial component of "bottom-up" nociceptive drive to RVM pain-modulating neurons is relayed through the PB. While the PB is well known as an important relay for ascending nociceptive information, its functional connection with the RVM allows the spinoparabrachial pathway to access descending control systems as part of a recurrent circuit.
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15
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Khasabov SG, Malecha P, Noack J, Tabakov J, Giesler GJ, Simone DA. Hyperalgesia and sensitization of dorsal horn neurons following activation of NK-1 receptors in the rostral ventromedial medulla. J Neurophysiol 2017; 118:2727-2744. [PMID: 28794197 PMCID: PMC5675905 DOI: 10.1152/jn.00478.2017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 08/04/2017] [Accepted: 08/06/2017] [Indexed: 11/22/2022] Open
Abstract
Neurons in the rostral ventromedial medulla (RVM) project to the spinal cord and are involved in descending modulation of pain. Several studies have shown that activation of neurokinin-1 (NK-1) receptors in the RVM produces hyperalgesia, although the underlying mechanisms are not clear. In parallel studies, we compared behavioral measures of hyperalgesia to electrophysiological responses of nociceptive dorsal horn neurons produced by activation of NK-1 receptors in the RVM. Injection of the selective NK-1 receptor agonist Sar9,Met(O2)11-substance P (SSP) into the RVM produced dose-dependent mechanical and heat hyperalgesia that was blocked by coadministration of the selective NK-1 receptor antagonist L-733,060. In electrophysiological studies, responses evoked by mechanical and heat stimuli were obtained from identified high-threshold (HT) and wide dynamic range (WDR) neurons. Injection of SSP into the RVM enhanced responses of WDR neurons, including identified neurons that project to the parabrachial area, to mechanical and heat stimuli. Since intraplantar injection of capsaicin produces robust hyperalgesia and sensitization of nociceptive spinal neurons, we examined whether this sensitization was dependent on NK-1 receptors in the RVM. Pretreatment with L-733,060 into the RVM blocked the sensitization of dorsal horn neurons produced by capsaicin. c-Fos labeling was used to determine the spatial distribution of dorsal horn neurons that were sensitized by NK-1 receptor activation in the RVM. Consistent with our electrophysiological results, administration of SSP into the RVM increased pinch-evoked c-Fos expression in the dorsal horn. It is suggested that targeting this descending pathway may be effective in reducing persistent pain.NEW & NOTEWORTHY It is known that activation of neurokinin-1 (NK-1) receptors in the rostral ventromedial medulla (RVM), a main output area for descending modulation of pain, produces hyperalgesia. Here we show that activation of NK-1 receptors produces hyperalgesia by sensitizing nociceptive dorsal horn neurons. Targeting this pathway at its origin or in the spinal cord may be an effective approach for pain management.
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Affiliation(s)
- Sergey G Khasabov
- Department of Diagnostic and Biological Sciences, University of Minnesota, School of Dentistry, Minneapolis, Minnesota; and
| | - Patrick Malecha
- Department of Diagnostic and Biological Sciences, University of Minnesota, School of Dentistry, Minneapolis, Minnesota; and
| | - Joseph Noack
- Department of Diagnostic and Biological Sciences, University of Minnesota, School of Dentistry, Minneapolis, Minnesota; and
| | - Janneta Tabakov
- Department of Diagnostic and Biological Sciences, University of Minnesota, School of Dentistry, Minneapolis, Minnesota; and
| | - Glenn J Giesler
- Department of Neuroscience, University of Minnesota, School of Medicine, Minneapolis, Minnesota
| | - Donald A Simone
- Department of Diagnostic and Biological Sciences, University of Minnesota, School of Dentistry, Minneapolis, Minnesota; and
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16
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Guy N, Voisin D, Mulliez A, Clavelou P, Dallel R. Medication overuse reinstates conditioned pain modulation in women with migraine. Cephalalgia 2017; 38:1148-1158. [DOI: 10.1177/0333102417727545] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background This study investigated the effects of medication overuse and withdrawal on modulation of pain processing in women with migraine. Temporal summation of laser-evoked thermal pain was used to measure the effects of conditioned pain modulation. Methods 36 female participants (12 healthy volunteers, 12 with episodic migraine and 12 with medication overuse headache) were included in a two session protocol. Medication overuse headache subjects were also tested three weeks after medication overuse headache withdrawal. Mechanical and laser-evoked thermal pain thresholds were measured on the back of the non-dominant hand where, later, temporal summation of laser-evoked thermal pain to repetitive thermal stimuli was elicited for 30 min, at an intensity producing moderate pain. Between the 10th and 20th minutes, the contralateral foot was immersed into a water bath at a not painful (30℃) or painfully cold (8℃; conditioned pain modulation) temperature. Results Episodic migraine, medication overuse headache and medication overuse headache withdrawal were associated with an increase in extracephalic temporal summation of laser-evoked thermal pain as compared to healthy volunteer subjects, while there was no alteration of laser-evoked thermal and mechanical extracephalic pain thresholds in these subjects. Conditioned pain modulation was highly efficient in temporal summation of laser-evoked thermal pain in healthy volunteer subjects, with a solid post-effect (reduction of pain). Conditioned pain modulation was still present, but reduced, in episodic migraine. By contrast, conditioned pain modulation was normal in medication overuse headache and strongly reduced in medication overuse headache withdrawal. Furthermore, in medication overuse headache withdrawal, the post-effect was no longer a decrease, but a facilitation of pain. Conclusions These data show that a decrease in conditioned pain modulation does not underlie medication overuse headache in women. On the contrary, medication overuse reinstated conditioned pain modulation in female migraine patients. They also identify different phenotypes of pain modulation in migraine patients. Registration number N° 2008-A00471-54.
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Affiliation(s)
- Nathalie Guy
- Université Clermont Auvergne, Clermont-Ferrand, France
- CHU Clermont-Ferrand, Clermont-Ferrand, France
- Inserm U1107, Neuro-Dol, Clermont-Ferrand, France
| | - Daniel Voisin
- Neurocentre Magendie, Inserm U1215, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
| | | | - Pierre Clavelou
- Université Clermont Auvergne, Clermont-Ferrand, France
- CHU Clermont-Ferrand, Clermont-Ferrand, France
- Inserm U1107, Neuro-Dol, Clermont-Ferrand, France
| | - Radhouane Dallel
- Université Clermont Auvergne, Clermont-Ferrand, France
- CHU Clermont-Ferrand, Clermont-Ferrand, France
- Inserm U1107, Neuro-Dol, Clermont-Ferrand, France
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17
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Optogenetic Evidence for a Direct Circuit Linking Nociceptive Transmission through the Parabrachial Complex with Pain-Modulating Neurons of the Rostral Ventromedial Medulla (RVM). eNeuro 2017; 4:eN-NWR-0202-17. [PMID: 28660248 PMCID: PMC5483601 DOI: 10.1523/eneuro.0202-17.2017] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 06/09/2017] [Indexed: 11/28/2022] Open
Abstract
The parabrachial complex (PB) is a functionally and anatomically complex structure involved in a range of homeostatic and sensory functions, including nociceptive transmission. There is also evidence that PB can engage descending pain-modulating systems, the best characterized of which is the rostral ventromedial medulla (RVM). Two distinct classes of RVM neurons, “ON-cells” and “OFF-cells,” exert net pronociceptive and anti-nociceptive effects, respectively. PB was recently shown to be a relay of nociceptive information to RVM ON- and OFF-cells. The present experiments used optogenetic methods in a lightly anesthetized rat and an adult RVM slice to determine whether there are direct, functionally relevant inputs to RVM pain-modulating neurons from PB. Whole-cell patch-clamp recordings demonstrated that PB conveys direct glutamatergic and GABAergic inputs to RVM neurons. Consistent with this, in vivo recording showed that nociceptive-evoked responses of ON- and OFF-cells were suppressed by optogenetic inactivation of archaerhodopsin (ArchT)-expressing PB terminals in RVM, demonstrating that a net inhibitory input to OFF-cells and net excitatory input to ON-cells are engaged by acute noxious stimulation. Further, the majority of ON- and OFF-cells responded to optogenetic activation of channelrhodopsin (ChR2)-expressing terminals in the RVM, confirming a direct PB influence on RVM pain-modulating neurons. These data show that a direct connection from the PB to the RVM conveys nociceptive information to the pain-modulating neurons of RVM under basal conditions. They also reveal additional inputs from PB with the capacity to activate both classes of RVM pain-modulating neurons and the potential to be recruited under different physiological and pathophysiological conditions.
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18
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Saito H, Katagiri A, Okada S, Mikuzuki L, Kubo A, Suzuki T, Ohara K, Lee J, Gionhaku N, Iinuma T, Bereiter DA, Iwata K. Ascending projections of nociceptive neurons from trigeminal subnucleus caudalis: A population approach. Exp Neurol 2017; 293:124-136. [PMID: 28366470 DOI: 10.1016/j.expneurol.2017.03.024] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 03/25/2017] [Accepted: 03/29/2017] [Indexed: 12/14/2022]
Abstract
Second-order neurons in trigeminal subnucleus caudalis (Vc) and upper cervical spinal cord (C1) are critical for craniofacial pain processing and project rostrally to terminate in: ventral posteromedial thalamic nucleus (VPM), medial thalamic nuclei (MTN) and parabrachial nuclei (PBN). The contribution of each region to trigeminal nociception was assessed by the number of phosphorylated extracellular signal-regulated kinase-immunoreactive (pERK-IR) neurons co-labeled with fluorogold (FG). The phenotype of pERK-IR neurons was further defined by the expression of neurokinin 1 receptor (NK1). The retrograde tracer FG was injected into VPM, MTN or PBN of the right hemisphere and after seven days, capsaicin was injected into the left upper lip in male rats. Nearly all pERK-IR neurons were found in superficial laminae of Vc-C1 ipsilateral to the capsaicin injection. Nearly all VPM and MTN FG-labeled neurons in Vc-C1 were found contralateral to the injection site, whereas FG-labeled neurons were found bilaterally after PBN injection. The percentage of FG-pERK-NK1-IR neurons was significantly greater (>10%) for PBN projection neurons than for VPM and MTN projection neurons (<3%). pERK-NK1-IR VPM projection neurons were found mainly in the middle-Vc, while pERK-NK1-immunoreactive MTN or PBN projection neurons were found in the middle-Vc and caudal Vc-C1. These results suggest that a significant percentage of capsaicin-responsive neurons in superficial laminae of Vc-C1 project directly to PBN, while neurons that project to VPM and MTN are subject to greater modulation by pERK-IR local interneurons. Furthermore, the rostrocaudal distribution differences of FG-pERK-NK1-IR neurons in Vc-C1 may reflect functional differences between these projection areas regarding craniofacial pain.
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Affiliation(s)
- Hiroto Saito
- Department of Complete Denture Prosthodontics, Nihon University School of Dentistry, 1-8-13 Kandasurugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Department of Physiology, Nihon University School of Dentistry, 1-8-13 Kandasurugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
| | - Ayano Katagiri
- Department of Physiology, Nihon University School of Dentistry, 1-8-13 Kandasurugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
| | - Shinji Okada
- Department of Complete Denture Prosthodontics, Nihon University School of Dentistry, 1-8-13 Kandasurugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Department of Physiology, Nihon University School of Dentistry, 1-8-13 Kandasurugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
| | - Lou Mikuzuki
- Department of Physiology, Nihon University School of Dentistry, 1-8-13 Kandasurugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Department of Psychosomatic Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima Bunkyo-ku, Tokyo 113-8510, Japan.
| | - Asako Kubo
- Department of Physiology, Nihon University School of Dentistry, 1-8-13 Kandasurugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
| | - Tatsuro Suzuki
- Department of Physiology, Nihon University School of Dentistry, 1-8-13 Kandasurugadai, Chiyoda-ku, Tokyo 101-8310, Japan; Department of Periodontology, Nihon University School of Dentistry, 1-8-13 Kandasurugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
| | - Kinuyo Ohara
- Department of Endodontics, Nihon University School of Dentistry, 1-8-13 Kandasurugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
| | - Jun Lee
- Department of Complete Denture Prosthodontics, Nihon University School of Dentistry, 1-8-13 Kandasurugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
| | - Nobuhito Gionhaku
- Department of Complete Denture Prosthodontics, Nihon University School of Dentistry, 1-8-13 Kandasurugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
| | - Toshimitsu Iinuma
- Department of Complete Denture Prosthodontics, Nihon University School of Dentistry, 1-8-13 Kandasurugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
| | - David A Bereiter
- Department of Diagnostic and Biological Sciences, University of Minnesota School of Dentistry, Minneapolis, MN 55455, USA.
| | - Koichi Iwata
- Department of Physiology, Nihon University School of Dentistry, 1-8-13 Kandasurugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
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Torta DM, Churyukanov MV, Plaghki L, Mouraux A. The effect of heterotopic noxious conditioning stimulation on Aδ-, C- and Aβ-fibre brain responses in humans. Eur J Neurosci 2015; 42:2707-15. [PMID: 26369522 DOI: 10.1111/ejn.13071] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 09/07/2015] [Accepted: 09/07/2015] [Indexed: 11/28/2022]
Abstract
Human studies have shown that heterotopic nociceptive conditioning stimulation (HNCS) applied to a given body location reduces the percept and brain responses elicited by noxious test stimuli delivered at a remote body location. It remains unclear to what extent this effect of HNCS relies on the spinal-bulbar-spinal loop mediating the effect of diffuse noxious inhibitory controls (DNICs) described in animals, and/or on top-down cortical mechanisms modulating nociception. Importantly, some studies have examined the effects of HNCS on the brain responses to nociceptive input conveyed by Aδ-fibres. In contrast, no studies have explored the effects of HNCS on the responses to selective nociceptive C-fibre input and non-nociceptive Aβ-fibre input. In this study, we measured the intensity of perception and event-related potentials (ERPs) to stimuli activating Aδ-, C- and Aβ-fibres, before, during and after HNCS, obtained by immersing one foot in painful cold water. We observed that (i) the perceived intensity of nociceptive Aδ- and C-stimuli was reduced during HNCS, and (ii) the ERPs elicited by Aδ- and Aβ- and C-stimuli were also reduced during HNCS. Importantly, because Aβ-ERPs are related to primary afferents that ascend directly through the dorsal columns without being relayed at spinal level, the modulation of these responses may not be explained by an influence of descending projections modulating the transmission of nociceptive input at spinal level. Therefore, our results indicate that, in humans, HNCS should be used with caution as a direct measure of DNIC-related mechanisms.
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Affiliation(s)
- Diana M Torta
- Laboratoire d'algologie, Institute of Neurosciences (IONS), Université catholique de Louvain, 53, Avenue Mounier - UCL 53.75, B-1200, Bruxelles, Belgium
| | - Maxim V Churyukanov
- Laboratoire d'algologie, Institute of Neurosciences (IONS), Université catholique de Louvain, 53, Avenue Mounier - UCL 53.75, B-1200, Bruxelles, Belgium.,A. Ya. Kozhevnikov Clinic of Nervous Diseases, The I.M. Sechenov First Moscow State Medical University, Moscow, Russia
| | - Leon Plaghki
- Laboratoire d'algologie, Institute of Neurosciences (IONS), Université catholique de Louvain, 53, Avenue Mounier - UCL 53.75, B-1200, Bruxelles, Belgium
| | - André Mouraux
- Laboratoire d'algologie, Institute of Neurosciences (IONS), Université catholique de Louvain, 53, Avenue Mounier - UCL 53.75, B-1200, Bruxelles, Belgium
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20
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Chebbi R, Boyer N, Monconduit L, Artola A, Luccarini P, Dallel R. The nucleus raphe magnus OFF-cells are involved in diffuse noxious inhibitory controls. Exp Neurol 2014; 256:39-45. [PMID: 24681000 DOI: 10.1016/j.expneurol.2014.03.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 03/01/2014] [Accepted: 03/14/2014] [Indexed: 12/11/2022]
Abstract
Diffuse noxious inhibitory controls (DNIC) are very powerful long-lasting descending inhibitory controls which are pivotal in modulating the activity of spinal and trigeminal nociceptive neurons. DNIC are subserved by a loop involving supraspinal structures such as the lateral parabrachial nucleus and the subnucleus reticularis dorsalis. Surprisingly, though, whether the nucleus raphe magnus (NRM), another supraspinal area which is long known to be important in pain modulation, is involved in DNIC is still a matter of discussion. Here, we reassessed the role of the NRM neurons in DNIC by electrophysiologically recording from wide dynamic range (WDR) neurons in the trigeminal subnucleus oralis and pharmacologically manipulating the NRM OFF- and ON-cells. In control conditions, C-fiber-evoked responses in trigeminal WDR neurons are inhibited by a conditioning noxious heat stimulation applied to the hindpaw. We show that inactivating the NRM by microinjecting the GABAA receptor agonist, muscimol, both facilitates C-fiber-evoked responses of trigeminal WDR neurons and strongly attenuates their inhibition by heat applied to the hindpaw. Interestingly, selective blockade of ON-cells by microinjecting the broad-spectrum excitatory amino acid antagonist, kynurenate, into the NRM neither affects C-fiber-evoked responses nor attenuates DNIC of trigeminal WDR neurons. These results indicate that the NRM tonically inhibits trigeminal nociceptive inputs and is involved in the neuronal network underlying DNIC. Moreover, within NRM, OFF-cells might be more specifically involved in both the tonic and phasic descending inhibitory controls of trigeminal nociception.
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Affiliation(s)
- R Chebbi
- Clermont Université, Université d'Auvergne, NEURO-DOL, BP 10448, F-63000 Clermont-Ferrand, France; INSERM, U1107, F-63001 Clermont-Ferrand, France; Faculté de médecine dentaire, Monastir, Tunisie
| | - N Boyer
- Clermont Université, Université d'Auvergne, NEURO-DOL, BP 10448, F-63000 Clermont-Ferrand, France; INSERM, U1107, F-63001 Clermont-Ferrand, France
| | - L Monconduit
- Clermont Université, Université d'Auvergne, NEURO-DOL, BP 10448, F-63000 Clermont-Ferrand, France; INSERM, U1107, F-63001 Clermont-Ferrand, France
| | - A Artola
- Clermont Université, Université d'Auvergne, NEURO-DOL, BP 10448, F-63000 Clermont-Ferrand, France; INSERM, U1107, F-63001 Clermont-Ferrand, France
| | - P Luccarini
- Clermont Université, Université d'Auvergne, NEURO-DOL, BP 10448, F-63000 Clermont-Ferrand, France; INSERM, U1107, F-63001 Clermont-Ferrand, France
| | - R Dallel
- Clermont Université, Université d'Auvergne, NEURO-DOL, BP 10448, F-63000 Clermont-Ferrand, France; INSERM, U1107, F-63001 Clermont-Ferrand, France.
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Wang N, Shi M, Wang JY, Luo F. Brain-network mechanisms underlying the divergent effects of depression on spontaneous versus evoked pain in rats: a multiple single-unit study. Exp Neurol 2013; 250:165-75. [PMID: 24100021 DOI: 10.1016/j.expneurol.2013.09.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 09/18/2013] [Accepted: 09/24/2013] [Indexed: 12/23/2022]
Abstract
Studies have reported divergent behavioral effects of depression on spontaneous vs. stimulus-evoked pain. However, the underlying neurobiological mechanisms are still unclear. The present study used a depression model of unpredictable chronic mild stress (UCMS) and pain models for spontaneous pain (i.e., the formalin test) and acute evoked pain (i.e., noxious thermal stimulation) in rats. The activity of neurons within thalamo-cortical circuits in the lateral and medial pain pathways was recorded by a multiple-channel recording technique, and behaviors were observed simultaneously. The results confirmed our previous findings that rats exposed to UCMS tended to exhibit decreased pain sensitivity to experimental stimuli but increased behavioral responses to ongoing pain. Based on the analysis of single-unit responses, the results demonstrated that the processing of spontaneous vs. evoked pain in a depressive-like state was altered in the opposite direction (activation vs. inhibition). The ensemble encoding analysis revealed that exposure to UCMS gave rise to enhanced inter-regional functional connectivity in spontaneous pain processing, but did not influence that of evoked pain. In addition, different brain activation patterns underlying the processing of spontaneous vs. evoked pain were observed. These findings revealed that the distinct response patterns of neurons within the pain-related brain circuits, especially in the affective pain pathway, mediate the divergent effects of depression on spontaneous vs. evoked pain. This is also the first report on the electrophysiology of depression models that provides direct evidence that the effect of depression on spontaneous and evoked pain may involve different brain mechanisms.
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Affiliation(s)
- Ning Wang
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China
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22
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Cardiovascular influences on conditioned pain modulation. Pain 2013; 154:1377-82. [DOI: 10.1016/j.pain.2013.04.027] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 04/09/2013] [Accepted: 04/11/2013] [Indexed: 01/07/2023]
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23
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Normandin A, Luccarini P, Molat JL, Gendron L, Dallel R. Spinal μ and δ opioids inhibit both thermal and mechanical pain in rats. J Neurosci 2013; 33:11703-14. [PMID: 23843537 PMCID: PMC3855450 DOI: 10.1523/jneurosci.1631-13.2013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Revised: 06/04/2013] [Accepted: 06/07/2013] [Indexed: 11/21/2022] Open
Abstract
The expression and contribution of μ (MOPR) and δ opioid receptors (DOPR) in polymodal nociceptors have been recently challenged. Indeed, MOPR and DOPR were shown to be expressed in distinct subpopulation of nociceptors where they inhibit pain induced by noxious heat and mechanical stimuli, respectively. In the present study, we used electrophysiological measurements to assess the effect of spinal MOPR and DOPR activation on heat-induced and mechanically induced diffuse noxious inhibitory controls (DNICs). We recorded from wide dynamic range neurons in the spinal trigeminal nucleus of anesthetized rats. Trains of 105 electrical shocks were delivered to the excitatory cutaneous receptive field. DNICs were triggered either by immersion of the hindpaw in 49°C water or application of 300 g of mechanical pressure. To study the involvement of peptidergic primary afferents in the activation of DNIC by noxious heat and mechanical stimulations, substance P release was measured in the spinal cord by visualizing neurokinin type 1 receptor internalization. We found that the activation of spinal MOPR and DOPR similarly attenuates the DNIC and neurokinin type 1 receptor internalization induced either by heat or mechanical stimuli. Our results therefore reveal that the activation of spinal MOPR and DOPR relieves both heat-induced and mechanically induced pain with similar potency and suggest that these receptors are expressed on polymodal, substance P-expressing neurons.
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Affiliation(s)
- Audrey Normandin
- Département de physiologie et biophysique, Faculté de médecine et des sciences de la santé
| | - Philippe Luccarini
- Clermont Université, Université d'Auvergne, NEURO-DOL, BP 10448, F-63000, CLERMONT-FERRAND Inserm, U1107, F-63001 Clermont-Ferrand, France
| | - Jean-Louis Molat
- Clermont Université, Université d'Auvergne, NEURO-DOL, BP 10448, F-63000, CLERMONT-FERRAND Inserm, U1107, F-63001 Clermont-Ferrand, France
| | - Louis Gendron
- Département de physiologie et biophysique, Faculté de médecine et des sciences de la santé
- Institut de pharmacologie de Sherbrooke, and
- Centre de recherche clinique Étienne-Le Bel, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada, and
| | - Radhouane Dallel
- Clermont Université, Université d'Auvergne, NEURO-DOL, BP 10448, F-63000, CLERMONT-FERRAND Inserm, U1107, F-63001 Clermont-Ferrand, France
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Nicholson KJ, Quindlen JC, Winkelstein BA. Development of a duration threshold for modulating evoked neuronal responses after nerve root compression injury. STAPP CAR CRASH JOURNAL 2011; 55:1-24. [PMID: 22869302 DOI: 10.4271/2011-22-0001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Cervical nerve roots are susceptible to compression injuries of various durations. The duration of an applied compression has been shown to contribute to both the onset of persistent pain and also the degree of spinal cellular and molecular responses related to nociception. This study investigated the relationship between peripherally-evoked activity in spinal cord neurons during a root compression and the resulting development of axonal damage. Electrically-evoked spikes were measured in the spinal cord as a function of time during and after (post-compression) a 15 minute compression of the C7 nerve root. Compression to the root significantly (p=0.035) reduced the number of spikes that were evoked over time relative to sham. The critical time for compression to maximally reduce evoked spikes was 6.6±3.0 minutes. A second study measured the post- compression evoked neuronal activity following compression applied for a shorter, sub-threshold time (three minutes). Ten minutes after compression was removed, the discharge rate remained significantly (p=0.018) less than baseline by 58±25% relative to sham after the 15 minute compression, but returned to within 3±33% of baseline after the three minute compression. Axonal damage was evident in the nerve root at day seven after nerve root compression only after a 15 minute compression. These studies demonstrate that even a transient mechanical insult to the nerve root is sufficient to induce sustained neuronal dysfunction and axonal pathology associated with pain, and results provide support that such minor neural tissue traumas can actually induce long-lasting functional deficits.
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Affiliation(s)
- Kristen J Nicholson
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104-6321, USA
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25
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Tonic and phasic descending dopaminergic controls of nociceptive transmission in the medullary dorsal horn. Pain 2011; 152:1821-1831. [DOI: 10.1016/j.pain.2011.03.030] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Revised: 03/23/2011] [Accepted: 03/24/2011] [Indexed: 12/27/2022]
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Knudsen L, Petersen GL, Nørskov KN, Vase L, Finnerup N, Jensen TS, Svensson P. Review of neuroimaging studies related to pain modulation. Scand J Pain 2011; 2:108-120. [DOI: 10.1016/j.sjpain.2011.05.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Accepted: 05/18/2011] [Indexed: 12/28/2022]
Abstract
Abstract
Background and purpose: A noxious stimulus does not necessarily cause pain. Nociceptive signals arising from a noxious stimulus are subject to modulation via endogenous inhibitory and facilitatory mechanisms as they travel from the periphery to the dorsal horn or brainstem and on to higher brain sites. Research on the neural structures underlying endogenous pain modulation has largely been restricted to animal research due to the invasiveness of such studies (e.g., spinal cord transection, brain lesioning, brain site stimulation). Neuroimaging techniques (e.g., magnetoencephalography (MEG), positron emission tomography (PET) and functional magnetic resonance imaging (fMRI)) provide non-invasive means to study neural structures in humans. The aim is to provide a narrative review of neuroimaging studies related to human pain control mechanisms.
Methods: The approach taken is to summarise specific pain modulation mechanisms within the somatosensory (diffuse noxious inhibitory controls, acupuncture, movement), affective (depression, anxiety, catastrophizing, stress) and cognitive (anticipation/placebo, attention/distraction, hypnosis)domains with emphasis on the contribution of neuroimaging studies.
Results and conclusions: Findings from imaging studies are complex reflecting activation or deactivation in numerous brain areas. Despite this, neuroimaging techniques have clarified supraspinal sites involved in a number of pain control mechanisms. The periaqueductal grey (PAG) is one area that has consistently been shown to be activated across the majority of pain mechanisms. Activity in the rostral ventromedial medulla known to relay descending modulation from the PAG, has also been observed both during acupuncture analgesia and anxiety-induced hyperalgesia. Other brain areas that appear to be involved in a number of mechanisms are the anterior cingulate cortex, prefrontal cortex, orbitofrontal cortex and nucleus accumbens, but their exact role is less clear.
Implications: Neuroimaging studies have provided essential information about the pain modulatory pathways under normal conditions, but much is still to be determined. Understanding the mechanisms of pain control is important for understanding the mechanisms that contribute to failed pain control in chronic pain. Applying fMRI outside the brain, such as in the trigeminal nucleus caudalis of the spinotrigeminal pathway and in the dorsal horn of the spinal cord, and coupling brain activity with activity at these sites may help improve our understanding of the function of brain sites and shed light on functional connectivity in the pain pathway.
© 2011 Scandinavian Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
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Affiliation(s)
- Lone Knudsen
- Danish Pain Research Center , Aarhus University Hospital Nørrebrogade 44, Building 1A , 8000 Aarhus C , Denmark
| | - Gitte Laue Petersen
- School of Psychology , Aarhus University, Jens Chr. Skous Vej 4 , 8000 Aarhus C , Denmark
| | | | - Lene Vase
- School of Psychology , Aarhus University, Jens Chr. Skous Vej 4 , 8000 Aarhus C , Denmark
| | - Nanna Finnerup
- Danish Pain Research Center , Aarhus University Hospital Nørrebrogade 44, Building 1A , 8000 Aarhus C , Denmark
- Center for Functionally Integrative Neuroscience, MindLab , Aarhus University Hospital, Nørrebrogade 44, Building 10G , 8000 Aarhus C , Denmark
| | - Troels Staehelin Jensen
- Danish Pain Research Center , Aarhus University Hospital Nørrebrogade 44, Building 1A , 8000 Aarhus C , Denmark
- Center for Functionally Integrative Neuroscience, MindLab , Aarhus University Hospital, Nørrebrogade 44, Building 10G , 8000 Aarhus C , Denmark
| | - Peter Svensson
- Center for Functionally Integrative Neuroscience, MindLab , Aarhus University Hospital, Nørrebrogade 44, Building 10G , 8000 Aarhus C , Denmark
- Department of Clinical Oral Physiology, School of Dentistry , Aarhus University, Vennelyst Boulevard 9 , 8000 Aarhus C , Denmark
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27
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Sprenger C, Bingel U, Büchel C. Treating pain with pain: supraspinal mechanisms of endogenous analgesia elicited by heterotopic noxious conditioning stimulation. Pain 2010; 152:428-439. [PMID: 21196078 DOI: 10.1016/j.pain.2010.11.018] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2010] [Revised: 11/03/2010] [Accepted: 11/16/2010] [Indexed: 10/18/2022]
Abstract
While being exposed to an intensive tonic pain stimulus at one area of the body, another phasic pain stimulus applied to a remote site is perceived as less painful. The neurophysiological basis for this "pain inhibits pain" phenomenon has been presumed to be an activation of the spino-bulbo-spinal mechanism termed "diffuse noxious inhibitory controls." However, several additional mechanisms such as an activation of the descending pain control system may contribute to this observation. Here we investigated the underlying supraspinal mechanisms of "heterotopic noxious conditioning stimulations" (HNCS), representing this specific experimental constellation. We used functional magnetic resonance imaging and behavioral recordings in combination with a modified cold-pressor task and phasic painful stimuli, and investigated the contribution of endogenous opioids to this mechanism using the opioid antagonist naloxone in a double-blind crossover design. HNCS led to marked endogenous analgesia and this effect correlated positively with the perceived intensity of the tonic painful stimulus. Furthermore, HNCS was paralleled by reduced blood oxygen level dependent (BOLD) responses in classical pain-responsive regions. Conversely, HNCS led to tonic BOLD increases in subregions of the anterior cingulate cortex. The strength of functional coupling between the subgenual anterior cingulate cortex and key structures of the descending pain control system was enhanced during HNCS, which correlated positively with the individual endogenous analgesia during HNCS. These effects were in part reversed by naloxone, speaking for the contribution of endogenous opioid neurotransmission to this mechanism. Taken together, these results demonstrate a substantial contribution of higher-order brain regions to the phenomenon of hypoalgesia during HNCS. Functional magnetic resonance imaging shows how the human brain is involved in heterotopic noxious conditioning and reveals active supraspinal pain modulatory mechanisms during dual pain stimulation.
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Affiliation(s)
- Christian Sprenger
- Department of Systems Neuroscience, University-Medical-Center Hamburg-Eppendorf, Hamburg, Germany Department of Neurology, University-Medical-Center Hamburg-Eppendorf, Hamburg, Germany
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Tzabazis AZ, Niv SH, Manering NA, Klyukinov M, Cuellar JM, Bhatnagar A, Yeomans DC. Trigeminal antihyperalgesic effect of intranasal carbon dioxide. Life Sci 2010; 87:36-41. [PMID: 20561904 DOI: 10.1016/j.lfs.2010.05.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2010] [Revised: 04/28/2010] [Accepted: 05/13/2010] [Indexed: 10/19/2022]
Abstract
AIMS Clinical studies demonstrate attenuation of trigeminal-related pain states such as migraine by intranasal CO(2) application. This study investigated the underlying mechanisms of this observation and its potential use to reverse trigeminal pain and hypersensitivity. MAIN METHODS We used a behavioral rat model of capsaicin-induced trigeminal thermal hyperalgesia, intranasal CO2 application and several pharmacologic agents such as carbonic anhydrase, acid-sensing ion channels (ASICs), and TRPV1 blocker as well as acidic buffer solutions to investigate and mimic the underlying mechanism. KEY FINDINGS Intranasal CO(2) application produced a robust dose-dependent antihyperalgesic effect in rats that lasted at least one hour. Blockade of nasal carbonic anhydrase with a dorzolamide solution (Trusopt ophthalmic solution) showed only a non-significant decrease of the antihyperalgesic effect of intranasal CO(2) application. Pharmacologic blockade of ASICs or TRPV(1) receptor significantly attenuated the antihyperalgesic effect of CO(2) application. The effect of intranasal CO(2) application could be mimicked by application of pH 4, but not pH 5, buffer solution to the nasal mucosa. As with CO(2) application, the antihyperalgesic effect of intranasal pH 4 buffer was blocked by nasal application of antagonists to ASICs and TRPV(1) receptors. SIGNIFICANCE Our results indicate that intranasal CO(2) application results in a subsequent attenuation of trigeminal nociception, mediated by protonic activation of TRPV(1) and ASIC channels. A potential central mechanism for this attenuation is discussed. The antihyperalgesic effects of intranasal CO(2) application might be useful for the treatment of trigeminal pain states.
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Affiliation(s)
- Alexander Z Tzabazis
- Department of Anesthesia, Stanford University, 300 Pasteur Drive, Stanford, CA 94305-5117, USA.
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29
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van Wijk G, Veldhuijzen DS. Perspective on Diffuse Noxious Inhibitory Controls as a Model of Endogenous Pain Modulation in Clinical Pain Syndromes. THE JOURNAL OF PAIN 2010; 11:408-19. [DOI: 10.1016/j.jpain.2009.10.009] [Citation(s) in RCA: 204] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Revised: 09/28/2009] [Accepted: 10/26/2009] [Indexed: 11/16/2022]
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