1
|
De Preter CC, Heinricher MM. The 'in's and out's' of descending pain modulation from the rostral ventromedial medulla. Trends Neurosci 2024; 47:447-460. [PMID: 38749825 PMCID: PMC11168876 DOI: 10.1016/j.tins.2024.04.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 04/12/2024] [Accepted: 04/21/2024] [Indexed: 06/14/2024]
Abstract
The descending-pain modulating circuit controls the experience of pain by modulating transmission of sensory signals through the dorsal horn. This circuit's key output node, the rostral ventromedial medulla (RVM), integrates 'top-down' and 'bottom-up' inputs that regulate functionally defined RVM cell types, 'OFF-cells' and 'ON-cells', which respectively suppress or facilitate pain-related sensory processing. While recent advances have sought molecular definition of RVM cell types, conflicting behavioral findings highlight challenges involved in aligning functional and molecularly defined types. This review summarizes current understanding, derived primarily from rodent studies but with corroborating evidence from human imaging, of the role of RVM populations in pain modulation and persistent pain states and explores recent advances outlining inputs to, and outputs from, RVM pain-modulating neurons.
Collapse
Affiliation(s)
- Caitlynn C De Preter
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR 97239, USA; Department of Neurological Surgery, Oregon Health & Science University, Portland, OR 97239, USA
| | - Mary M Heinricher
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR 97239, USA; Department of Neurological Surgery, Oregon Health & Science University, Portland, OR 97239, USA.
| |
Collapse
|
2
|
Cramer N, Ji Y, Kane MA, Pilli NR, Castro A, Posa L, Van Patten G, Masri R, Keller A. Elevated Serotonin in Mouse Spinal Dorsal Horn Is Pronociceptive. eNeuro 2023; 10:ENEURO.0293-23.2023. [PMID: 37945351 DOI: 10.1523/eneuro.0293-23.2023] [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: 08/05/2023] [Revised: 10/27/2023] [Accepted: 10/31/2023] [Indexed: 11/12/2023] Open
Abstract
Serotonergic neurons in the rostral ventral medulla (RVM) contribute to bidirectional control of pain through modulation of spinal and trigeminal nociceptive networks. Deficits in this pathway are believed to contribute to pathologic pain states, but whether changes in serotonergic mechanisms are pro- or antinociceptive is debated. We used a combination of optogenetics and fiber photometry to examine these mechanisms more closely. We find that optogenetic activation of RVM serotonergic afferents in the spinal cord of naive mice produces mechanical hypersensitivity and conditioned place aversion (CPA). Neuropathic pain, produced by chronic constriction injury of the infraorbital nerve (CCI-ION), evoked a tonic increase in serotonin (5HT) concentrations within the spinal trigeminal nucleus caudalis (SpVc), measured with liquid chromatography-tandem mass spectroscopy (LC-MS/MS). By contract, CCI-ION had no effect on the phasic serotonin transients in SpVc, evoked by noxious pinch, and measured with fiber photometry of a serotonin sensor. These findings suggest that serotonin release in the spinal cord is pronociceptive and that an increase in sustained serotonin signaling, rather than phasic or event driven increases, potentiate nociception in models of chronic pain.
Collapse
Affiliation(s)
- Nathan Cramer
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201
- University of Maryland - Medicine Institute for Neuroscience Discovery, University of Maryland School of Medicine, Baltimore, MD 21201
- Center to Advance Chronic Pain Research, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Yadong Ji
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Dentistry, Baltimore, MD 21201
| | - Maureen A Kane
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201
| | - Nageswara R Pilli
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201
| | - Alberto Castro
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Luca Posa
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Gabrielle Van Patten
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Radi Masri
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Dentistry, Baltimore, MD 21201
- University of Maryland - Medicine Institute for Neuroscience Discovery, University of Maryland School of Medicine, Baltimore, MD 21201
- Center to Advance Chronic Pain Research, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Asaf Keller
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201
- University of Maryland - Medicine Institute for Neuroscience Discovery, University of Maryland School of Medicine, Baltimore, MD 21201
- Center to Advance Chronic Pain Research, University of Maryland School of Medicine, Baltimore, MD 21201
| |
Collapse
|
3
|
Cramer N, Ji Y, Kane M, Pilli N, Posa L, Patten GV, Masri R, Keller A. Elevated serotonin in mouse spinal dorsal horn is pronociceptive. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.10.552838. [PMID: 37645759 PMCID: PMC10461991 DOI: 10.1101/2023.08.10.552838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Serotonergic neurons in the rostral ventral medulla (RVM) contribute to bidirectional control of pain through modulation of spinal and trigeminal nociceptive networks. Deficits in this pathway are believed to contribute to pathological pain states, but whether changes in serotonergic mechanisms are pro or anti-nociceptive are debated. We used a combination of optogenetics and fiber photometry to examine these mechanisms more closely. We find that optogenetic activation of RVM serotonergic afferents in the spinal cord of naïve mice produces mechanical hypersensitivity and conditioned place aversion. Neuropathic pain, produced by chronic constriction injury of the infraorbital nerve (CCI-ION), evoked a tonic increase in serotonin concentrations within the spinal trigeminal nucleus caudalis (SpVc), measured with liquid chromatography-tandem mass spectroscopy (LC-MS/MS). By contract, CCI-ION had no effect on the phasic serotonin transients in SpVc, evoked by noxious pinch, and measured with fiber photometry of a serotonin sensor. These findings suggest that serotonin release in the spinal cord is pronociceptive and that an increase is sustained serotonin signaling, rather than phasic or event driven increases, potentiate nociception in models of chronic pain.
Collapse
Affiliation(s)
- Nathan Cramer
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
- UM-MIND, University of Maryland School of Medicine, Baltimore, Maryland 21201
- Center to Advance Chronic Pain Research, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Yadong Ji
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Dentistry, Baltimore, Maryland 21201
| | - Maureen Kane
- Department of Pharmaceutical Sciences University of Maryland School of Pharmacy, Baltimore, Maryland 21201
| | - Nageswara Pilli
- Department of Pharmaceutical Sciences University of Maryland School of Pharmacy, Baltimore, Maryland 21201
| | - Luca Posa
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Gabrielle Van Patten
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Radi Masri
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Dentistry, Baltimore, Maryland 21201
- UM-MIND, University of Maryland School of Medicine, Baltimore, Maryland 21201
- Center to Advance Chronic Pain Research, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Asaf Keller
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
- UM-MIND, University of Maryland School of Medicine, Baltimore, Maryland 21201
- Center to Advance Chronic Pain Research, University of Maryland School of Medicine, Baltimore, Maryland 21201
| |
Collapse
|
4
|
Piriyaprasath K, Hasegawa M, Kakihara Y, Iwamoto Y, Kamimura R, Saito I, Fujii N, Yamamura K, Okamoto K. Effects of stress contagion on anxiogenic- and orofacial inflammatory pain-like behaviors with brain activation in mice. Eur J Oral Sci 2023:e12942. [PMID: 37377104 DOI: 10.1111/eos.12942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 06/11/2023] [Indexed: 06/29/2023]
Abstract
The conditions of stress contagion are induced in bystanders without direct experiences of stressful events. This study determined the effects of stress contagion on masseter muscle nociception in mice. Stress contagion was developed in the bystanders after cohabitating with a conspecific mouse subjected to social defeat stress for 10 days. On Day 11, stress contagion increased anxiety- and orofacial inflammatory pain-like behaviors. The c-Fos and FosB immunoreactivities evoked by masseter muscle stimulation were increased in the upper cervical spinal cord, while c-Fos expressions were increased in the rostral ventromedial medulla, including the lateral paragigantocellular reticular nucleus and nucleus raphe magnus in stress contagion mice. The level of serotonin in the rostral ventromedial medulla was increased under stress contagion, while the number of serotonin positive cells was increased in the lateral paragigantocellular reticular nucleus. Stress contagion increased c-Fos and FosB expressions in the anterior cingulate cortex and insular cortex, both of which were positively correlated with orofacial inflammatory pain-like behaviors. The level of brain-derived neurotrophic factor was increased in the insular cortex under stress contagion. These results indicate that stress contagion can cause neural changes in the brain, resulting in increased masseter muscle nociception, as seen in social defeat stress mice.
Collapse
Affiliation(s)
- Kajita Piriyaprasath
- Division of Oral Physiology, Faculty of Dentistry and Graduate School of Medical and Dental Sciences, Niigata University, Niigata City, Japan
- Department of Restorative Dentistry, Faculty of Dentistry, Naresuan University, Phitsanulok, Thailand
| | - Mana Hasegawa
- Division of Oral Physiology, Faculty of Dentistry and Graduate School of Medical and Dental Sciences, Niigata University, Niigata City, Japan
- Division of General Dentistry and Dental Clinical Education Unit, Faculty of Dentistry and Graduate School of Medical and Dental Sciences, Niigata University, Niigata City, Japan
| | - Yoshito Kakihara
- Division of Dental Pharmacology, Faculty of Dentistry and Graduate School of Medical and Dental Sciences, Niigata University, Niigata City, Japan
| | - Yuya Iwamoto
- Division of Oral Physiology, Faculty of Dentistry and Graduate School of Medical and Dental Sciences, Niigata University, Niigata City, Japan
- Division of General Dentistry and Dental Clinical Education Unit, Faculty of Dentistry and Graduate School of Medical and Dental Sciences, Niigata University, Niigata City, Japan
| | - Rantaro Kamimura
- Division of Orthodontics, Faculty of Dentistry and Graduate School of Medical and Dental Sciences, Niigata University, Niigata City, Japan
| | - Isao Saito
- Division of Orthodontics, Faculty of Dentistry and Graduate School of Medical and Dental Sciences, Niigata University, Niigata City, Japan
| | - Noritaka Fujii
- Division of General Dentistry and Dental Clinical Education Unit, Faculty of Dentistry and Graduate School of Medical and Dental Sciences, Niigata University, Niigata City, Japan
| | - Kensuke Yamamura
- Division of Oral Physiology, Faculty of Dentistry and Graduate School of Medical and Dental Sciences, Niigata University, Niigata City, Japan
| | - Keiichiro Okamoto
- Division of Oral Physiology, Faculty of Dentistry and Graduate School of Medical and Dental Sciences, Niigata University, Niigata City, Japan
| |
Collapse
|
5
|
Aby F, Lorenzo LE, Grivet Z, Bouali-Benazzouz R, Martin H, Valerio S, Whitestone S, Isabel D, Idi W, Bouchatta O, De Deurwaerdere P, Godin AG, Herry C, Fioramonti X, Landry M, De Koninck Y, Fossat P. Switch of serotonergic descending inhibition into facilitation by a spinal chloride imbalance in neuropathic pain. SCIENCE ADVANCES 2022; 8:eabo0689. [PMID: 35895817 PMCID: PMC9328683 DOI: 10.1126/sciadv.abo0689] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 06/13/2022] [Indexed: 06/15/2023]
Abstract
Descending control from the brain to the spinal cord shapes our pain experience, ranging from powerful analgesia to extreme sensitivity. Increasing evidence from both preclinical and clinical studies points to an imbalance toward descending facilitation as a substrate of pathological pain, but the underlying mechanisms remain unknown. We used an optogenetic approach to manipulate serotonin (5-HT) neurons of the nucleus raphe magnus that project to the dorsal horn of the spinal cord. We found that 5-HT neurons exert an analgesic action in naïve mice that becomes proalgesic in an experimental model of neuropathic pain. We show that spinal KCC2 hypofunction turns this descending inhibitory control into paradoxical facilitation; KCC2 enhancers restored 5-HT-mediated descending inhibition and analgesia. Last, combining selective serotonin reuptake inhibitors (SSRIs) with a KCC2 enhancer yields effective analgesia against nerve injury-induced pain hypersensitivity. This uncovers a previously unidentified therapeutic path for SSRIs against neuropathic pain.
Collapse
Affiliation(s)
- Franck Aby
- Université de Bordeaux, Bordeaux, France
- Institut des maladies neurodégénératives (IMN), CNRS UMR 5293, Bordeaux, France
| | - Louis-Etienne Lorenzo
- CERVO Brain Research Center, Université Laval, Québec City, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec City, Canada
| | - Zoé Grivet
- Université de Bordeaux, Bordeaux, France
- Institut des maladies neurodégénératives (IMN), CNRS UMR 5293, Bordeaux, France
| | - Rabia Bouali-Benazzouz
- Université de Bordeaux, Bordeaux, France
- Institut des maladies neurodégénératives (IMN), CNRS UMR 5293, Bordeaux, France
| | - Hugo Martin
- NutriNeuro, UMR, INRAe, 1286 Bordeaux, France
| | | | - Sara Whitestone
- Université de Bordeaux, Bordeaux, France
- Institut des maladies neurodégénératives (IMN), CNRS UMR 5293, Bordeaux, France
| | - Dominique Isabel
- CERVO Brain Research Center, Université Laval, Québec City, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec City, Canada
| | - Walid Idi
- Université de Bordeaux, Bordeaux, France
- Institut des maladies neurodégénératives (IMN), CNRS UMR 5293, Bordeaux, France
| | - Otmane Bouchatta
- Université de Bordeaux, Bordeaux, France
- Institut des maladies neurodégénératives (IMN), CNRS UMR 5293, Bordeaux, France
- CERVO Brain Research Center, Université Laval, Québec City, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec City, Canada
- NutriNeuro, UMR, INRAe, 1286 Bordeaux, France
- Aquineuro, SA, Bordeaux, France
- Université Cadi Ayyad, Marrakech, Morocco
| | - Philippe De Deurwaerdere
- Université de Bordeaux, Bordeaux, France
- Institut des neurosciences cognitives et intégratives d’aquitaine (INCIA) CNRS UMR 5287, Bordeaux, France
| | - Antoine G. Godin
- CERVO Brain Research Center, Université Laval, Québec City, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec City, Canada
| | - Cyril Herry
- Neurocentre Magendie, INSERM, U862, Bordeaux, France
| | | | - Marc Landry
- Université de Bordeaux, Bordeaux, France
- Institut des maladies neurodégénératives (IMN), CNRS UMR 5293, Bordeaux, France
| | - Yves De Koninck
- CERVO Brain Research Center, Université Laval, Québec City, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec City, Canada
| | - Pascal Fossat
- Université de Bordeaux, Bordeaux, France
- Institut des maladies neurodégénératives (IMN), CNRS UMR 5293, Bordeaux, France
| |
Collapse
|
6
|
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.
Collapse
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
| |
Collapse
|
7
|
Abstract
PURPOSE OF REVIEW The goal of the review was to highlight recent advances in our understanding of descending pain-modulating systems and how these contribute to persistent pain states, with an emphasis on the current state of knowledge around "bottom-up" (sensory) and "top-down" (higher structures mediating cognitive and emotional processing) influences on pain-modulating circuits. RECENT FINDINGS The connectivity, physiology, and function of these systems have been characterized extensively over the last 30 years. The field is now beginning to ask how and when these systems are engaged to modulate pain. A recent focus is on the parabrachial complex, now recognized as the major relay of nociceptive information to pain-modulating circuits, and plasticity in this circuit and its connections to the RVM is marked in persistent inflammatory pain. Top-down influences from higher structures, including hypothalamus, amygdala, and medial prefrontal areas, are also considered. The challenge will be to tease out mechanisms through which a particular behavioral context engages distinct circuits to enhance or suppress pain, and to understand how these mechanisms contribute to chronic pain.
Collapse
|
8
|
Patel R, Dickenson AH. Modality selective roles of pro-nociceptive spinal 5-HT 2A and 5-HT 3 receptors in normal and neuropathic states. Neuropharmacology 2018; 143:29-37. [PMID: 30240783 PMCID: PMC6277848 DOI: 10.1016/j.neuropharm.2018.09.028] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 08/23/2018] [Accepted: 09/17/2018] [Indexed: 12/20/2022]
Abstract
Descending brainstem control of spinal nociceptive processing permits a dynamic and adaptive modulation of ascending sensory information. Chronic pain states are frequently associated with enhanced descending excitatory drive mediated predominantly through serotonergic neurones in the rostral ventromedial medulla. In this study, we examine the roles of spinal 5-HT2A and 5-HT3 receptors in modulating ascending sensory output in normal and neuropathic states. In vivo electrophysiology was performed in anaesthetised spinal nerve ligated (SNL) and sham-operated rats to record from wide dynamic range neurones in the ventral posterolateral thalamus. In sham rats, block of spinal 5-HT3Rs with ondansetron revealed tonic facilitation of noxious punctate mechanical stimulation, whereas blocking 5-HT2ARs with ketanserin had minimal effect on neuronal responses to evoked stimuli. The inhibitory profiles of both drugs were altered in SNL rats; ondansetron additionally inhibited neuronal responses to lower intensity punctate mechanical stimuli and noxious heat evoked responses, whereas ketanserin inhibited innocuous and noxious evaporative cooling evoked responses. Neither drug had any effect on dynamic brush evoked responses nor on spontaneous firing rates in both sham and SNL rats. These data identify novel modality and intensity selective facilitatory roles of spinal 5-HT2A and 5-HT3 receptors on sensory neuronal processing within the spinothalamic-somatosensory cortical pathway.
Collapse
Affiliation(s)
- Ryan Patel
- University College London, Gower Street, Department of Neuroscience, Physiology and Pharmacology, London, WC1E 6BT, UK.
| | - Anthony H Dickenson
- University College London, Gower Street, Department of Neuroscience, Physiology and Pharmacology, London, WC1E 6BT, UK
| |
Collapse
|
9
|
Neves RM, van Keulen S, Yang M, Logothetis NK, Eschenko O. Locus coeruleus phasic discharge is essential for stimulus-induced gamma oscillations in the prefrontal cortex. J Neurophysiol 2017; 119:904-920. [PMID: 29093170 DOI: 10.1152/jn.00552.2017] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The locus coeruleus (LC) noradrenergic (NE) neuromodulatory system is critically involved in regulation of neural excitability via its diffuse ascending projections. Tonic NE release in the forebrain is essential for maintenance of vigilant states and increases the signal-to-noise ratio of cortical sensory responses. The impact of phasic NE release on cortical activity and sensory processing is less explored. We previously reported that LC microstimulation caused a transient desynchronization of population activity in the medial prefrontal cortex (mPFC), similar to noxious somatosensory stimuli. The LC receives nociceptive information from the medulla and therefore may mediate sensory signaling to its forebrain targets. Here we performed extracellular recordings in LC and mPFC while presenting noxious stimuli in urethane-anesthetized rats. A brief train of foot shocks produced a robust phasic response in the LC and a transient change in the mPFC power spectrum, with the strongest modulation in the gamma (30-90 Hz) range. The LC phasic response preceded prefrontal gamma power increase, and cortical modulation was proportional to the LC excitation. We also quantitatively characterized distinct cortical states and showed that sensory responses in both LC and mPFC depend on the ongoing cortical state. Finally, cessation of the LC firing by bilateral local iontophoretic injection of clonidine, an α2-adrenoreceptor agonist, completely eliminated sensory responses in the mPFC without shifting cortex to a less excitable state. Together, our results suggest that the LC phasic response induces gamma power increase in the PFC and is essential for mediating sensory information along an ascending noxious pathway. NEW & NOTEWORTHY Our study shows linear relationships between locus coeruleus phasic excitation and the amplitude of gamma oscillations in the prefrontal cortex. Results suggest that the locus coeruleus phasic response is essential for mediating sensory information along an ascending noxious pathway.
Collapse
Affiliation(s)
- Ricardo M Neves
- Max Planck Institute for Biological Cybernetics , Tübingen , Germany
| | - Silvia van Keulen
- Max Planck Institute for Biological Cybernetics , Tübingen , Germany
| | - Mingyu Yang
- Max Planck Institute for Biological Cybernetics , Tübingen , Germany
| | - Nikos K Logothetis
- Max Planck Institute for Biological Cybernetics , Tübingen , Germany.,Centre for Imaging Sciences, Biomedical Imaging Institute, The University of Manchester , Manchester , United Kingdom
| | - Oxana Eschenko
- Max Planck Institute for Biological Cybernetics , Tübingen , Germany
| |
Collapse
|
10
|
Gautier A, Geny D, Bourgoin S, Bernard J, Hamon M. Differential innervation of superficial versus deep laminae of the dorsal horn by bulbo-spinal serotonergic pathways in the rat. IBRO Rep 2017; 2:72-80. [PMID: 30135935 PMCID: PMC6084826 DOI: 10.1016/j.ibror.2017.04.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 03/28/2017] [Accepted: 04/07/2017] [Indexed: 01/04/2023] Open
Abstract
Convergent data showed that bulbo-spinal serotonergic projections exert complex modulatory influences on nociceptive signaling within the dorsal horn. These neurons are located in the B3 area which comprises the median raphe magnus (RMg) and the lateral paragigantocellular reticular (LPGi) nuclei. Because LPGi 5-HT neurons differ from RMg 5-HT neurons regarding both their respective electrophysiological properties and responses to noxious stimuli, we used anatomical approaches for further characterization of the respective spinal projections of LPGi versus RMg 5-HT neuron subgroups. Adult Sprague-Dawley rats were stereotaxically injected into the RMg or the LPGi with the anterograde tracer Phaseolus vulgaris leucoagglutinin (PHA-L). The precise location of injection sites and RMg vs LPGi spinal projections into the different dorsal horn laminae were visualized by PHA-L immunolabeling. Double immunofluorescent labeling of PHA-L and the serotonin transporter (5-HTT) allowed detection of serotonergic fibers among bulbo-spinal projections. Anterograde tracing showed that RMg neurons project preferentially into the deep laminae V-VI whereas LPGi neuron projections are confined to the superficial laminae I-II of the ipsilateral dorsal horn. All along the spinal cord, double-labeled PHA-L/5-HTT immunoreactive fibers, which represent only 5-15% of all PHA-L-immunoreactive projections, exhibit the same differential locations depending on their origin in the RMg versus the LPGi. The clear-cut distinction between dorsal horn laminae receiving bulbo-spinal serotonergic projections from the RMg versus the LPGi provides further anatomical support to the idea that the descending serotonergic pathways issued from these two bulbar nuclei might exert different modulatory influences on the spinal relay of pain signaling neuronal pathways.
Collapse
Affiliation(s)
| | | | | | | | - M. Hamon
- INSERM UMR 894 - Centre de Psychiatrie et Neurosciences, Université Paris Descartes, 75014, Paris, France
| |
Collapse
|
11
|
Gautier A, El Ouaraki H, Bazin N, Salam S, Vodjdani G, Bourgoin S, Pezet S, Bernard JF, Hamon M. Lentiviral vector-driven inhibition of 5-HT synthesis in B3 bulbo-spinal serotonergic projections – Consequences on nociception, inflammatory and neuropathic pain in rats. Exp Neurol 2017; 288:11-24. [DOI: 10.1016/j.expneurol.2016.10.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 10/24/2016] [Accepted: 10/27/2016] [Indexed: 01/19/2023]
|
12
|
Sévoz-Couche C, Brouillard C. Key role of 5-HT 3 receptors in the nucleus tractus solitarii in cardiovagal stress reactivity. Neurosci Biobehav Rev 2016; 74:423-432. [PMID: 27131969 DOI: 10.1016/j.neubiorev.2016.04.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 04/18/2016] [Accepted: 04/20/2016] [Indexed: 01/01/2023]
Abstract
Serotonin plays a modulatory role in central control of the autonomic nervous system (ANS). The nucleus tractus solitarii (NTS) in the medulla is an area of viscerosomatic integration innervated by both central and peripheral serotonergic fibers. Influences from different origins therefore trigger the release of serotonin into the NTS and exert multiple influences on the ANS. This major influence on the ANS is also mediated by activation of several receptors in the NTS. In particular, the NTS is the central zone with the highest density of serotonin3 (5-HT3) receptors. In this review, we present evidence that 5-HT3 receptors in the NTS play a key role in one of the crucial homeostatic responses to acute and chronic stress: inhibitory modulation of the parasympathetic component of the ANS. The possible functional interactions of 5-HT3 receptors with GABAA and NK1 receptors in the NTS are also discussed.
Collapse
Affiliation(s)
- Caroline Sévoz-Couche
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, UMRS1158 Neurophysiologie Respiratoire Expérimentale et Clinique, Paris, France.
| | - Charly Brouillard
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, UMRS1158 Neurophysiologie Respiratoire Expérimentale et Clinique, Paris, France
| |
Collapse
|
13
|
Cleary DR, Roeder Z, Elkhatib R, Heinricher MM. Neuropeptide Y in the rostral ventromedial medulla reverses inflammatory and nerve injury hyperalgesia in rats via non-selective excitation of local neurons. Neuroscience 2014; 271:149-59. [PMID: 24792711 PMCID: PMC4071144 DOI: 10.1016/j.neuroscience.2014.04.035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 04/18/2014] [Accepted: 04/21/2014] [Indexed: 01/03/2023]
Abstract
Chronic pain reflects not only sensitization of the ascending nociceptive pathways, but also changes in descending modulation. The rostral ventromedial medulla (RVM) is a key structure in a well-studied descending pathway, and contains two classes of modulatory neurons, the ON-cells and the OFF-cells. Disinhibition of OFF-cells depresses nociception; increased ON-cell activity facilitates nociception. Multiple lines of evidence show that sensitization of ON-cells contributes to chronic pain, and reversing or blocking this sensitization is of interest as a treatment of persistent pain. Neuropeptide Y (NPY) acting via the Y1 receptor has been shown to attenuate hypersensitivity in nerve-injured animals without affecting normal nociception when microinjected into the RVM, but the neural basis for this effect was unknown. We hypothesized that behavioral anti-hyperalgesia was due to selective inhibition of ON-cells by NPY at the Y1 receptor. To explore the possibility of Y1 selectivity on ON-cells, we stained for the NPY-Y1 receptor in the RVM, and found it broadly expressed on both serotonergic and non-serotonergic neurons. In subsequent behavioral experiments, NPY microinjected into the RVM in lightly anesthetized animals reversed signs of mechanical hyperalgesia following either nerve injury or chronic hindpaw inflammation. Unexpectedly, rather than decreasing ON-cell activity, NPY increased spontaneous activity of both ON- and OFF-cells without altering noxious-evoked changes in firing. Based on these results, we conclude that the anti-hyperalgesic effects of NPY in the RVM are not explained by selective inhibition of ON-cells, but rather by increased spontaneous activity of OFF-cells. Although ON-cells undoubtedly facilitate nociception and contribute to hypersensitivity, the present results highlight the importance of parallel OFF-cell-mediated descending inhibition in limiting the expression of chronic pain.
Collapse
Affiliation(s)
- D R Cleary
- Department of Neurological Surgery, Oregon Health & Science University, Portland, OR, United States.
| | - Z Roeder
- Department of Neurological Surgery, Oregon Health & Science University, Portland, OR, United States
| | - R Elkhatib
- Department of Neurological Surgery, Oregon Health & Science University, Portland, OR, United States; Department of Anesthesia, Cairo University Hospital, Cairo, Egypt
| | - M M Heinricher
- Department of Neurological Surgery, Oregon Health & Science University, Portland, OR, United States; Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
| |
Collapse
|
14
|
Indo Y. Neurobiology of pain, interoception and emotional response: lessons from nerve growth factor-dependent neurons. Eur J Neurosci 2014; 39:375-91. [DOI: 10.1111/ejn.12448] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Revised: 10/31/2013] [Accepted: 11/09/2013] [Indexed: 01/01/2023]
Affiliation(s)
- Yasuhiro Indo
- Department of Pediatrics; Kumamoto University Hospital; Honjo 1-1-1, Chuou-ku Kumamoto 860-8556 Japan
| |
Collapse
|
15
|
On the g-protein-coupled receptor heteromers and their allosteric receptor-receptor interactions in the central nervous system: focus on their role in pain modulation. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 2013:563716. [PMID: 23956775 PMCID: PMC3730365 DOI: 10.1155/2013/563716] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 05/20/2013] [Accepted: 05/24/2013] [Indexed: 12/16/2022]
Abstract
The modulatory role of allosteric receptor-receptor interactions in the pain pathways of the Central Nervous System and the peripheral nociceptors has become of increasing interest. As integrators of nociceptive and antinociceptive wiring and volume transmission signals, with a major role for the opioid receptor heteromers, they likely have an important role in the pain circuits and may be involved in acupuncture. The delta opioid receptor (DOR) exerts an antagonistic allosteric influence on the mu opioid receptor (MOR) function in a MOR-DOR heteromer. This heteromer contributes to morphine-induced tolerance and dependence, since it becomes abundant and develops a reduced G-protein-coupling with reduced signaling mainly operating via β-arrestin2 upon chronic morphine treatment. A DOR antagonist causes a return of the Gi/o binding and coupling to the heteromer and the biological actions of morphine. The gender- and ovarian steroid-dependent recruitment of spinal cord MOR/kappa opioid receptor (KOR) heterodimers enhances antinociceptive functions and if impaired could contribute to chronic pain states in women. MOR1D heterodimerizes with gastrin-releasing peptide receptor (GRPR) in the spinal cord, mediating morphine induced itch. Other mechanism for the antinociceptive actions of acupuncture along meridians may be that it enhances the cross-desensitization of the TRPA1 (chemical nociceptor)-TRPV1 (capsaicin receptor) heteromeric channel complexes within the nociceptor terminals located along these meridians. Selective ionotropic cannabinoids may also produce cross-desensitization of the TRPA1-TRPV1 heteromeric nociceptor channels by being negative allosteric modulators of these channels leading to antinociception and antihyperalgesia.
Collapse
|