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The effects of a dopamine agonist (apomorphine) on experimental and spontaneous pain in patients with chronic radicular pain: A randomized, double-blind, placebo-controlled, cross-over study. PLoS One 2018; 13:e0195287. [PMID: 29621293 PMCID: PMC5886417 DOI: 10.1371/journal.pone.0195287] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 02/15/2018] [Indexed: 11/29/2022] Open
Abstract
Background Although evidence suggests that dopaminergic systems are involved in pain processing, the effects of dopaminergic interventions on pain remains questionable. This randomized, double blinded, placebo-controlled, cross-over study was aimed at exploring the effect of the dopamine agonist apomorphine on experimental pain evoked by cold stimulation and on spontaneous pain in patients with lumbar radicular (neuropathic) pain. Methods Data was collected from 35 patients with chronic lumbar radiculopathy (18 men, mean age 56.2±13 years). The following parameters were evaluated before (baseline) and 30, 75 and 120 minutes subsequent to a subcutaneous injection of 1.5 mg apomorphine or placebo: cold pain threshold and tolerance in the painful site (ice pack, affected leg) and in a remote non-painful site (12°C water bath, hand), and spontaneous (affected leg) pain intensity (NPS, 0–100). Results One-hundred and twenty minutes following apomorphine (but not placebo) injection, cold pain threshold and tolerance in the hand increased significantly compared to baseline (from a median of 8.0 seconds (IQR = 5.0) to 10 seconds (IQR = 9.0), p = 0.001 and from a median of 19.5 seconds (IQR = 30.2) to 27.0 seconds (IQR = 37.5), p<0.001, respectively). In addition, apomorphine prolonged cold pain tolerance but not threshold in the painful site (from a median of 43.0 seconds (IQR = 63.0) at baseline to 51.0 seconds (IQR = 78.0) at 120 min, p = 0.02). Apomorphine demonstrated no superiority over placebo in reducing spontaneous pain intensity. Conclusion These findings are in line with previous results in healthy subjects, showing that apomorphine increases the ability to tolerate cold pain and therefore suggesting that dopaminergic interventions can have potential clinical relevance.
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Pourreza P, Babapour V, Haghparast A. Role of dorsal hippocampal orexin-1 receptors in modulation of antinociception induced by chemical stimulation of the lateral hypothalamus. Physiol Behav 2018; 185:79-86. [DOI: 10.1016/j.physbeh.2017.12.036] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 12/28/2017] [Accepted: 12/29/2017] [Indexed: 11/29/2022]
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Cardoso-Cruz H, Dourado M, Monteiro C, Galhardo V. Blockade of dopamine D2 receptors disrupts intrahippocampal connectivity and enhances pain-related working memory deficits in neuropathic pain rats. Eur J Pain 2018; 22:1002-1015. [PMID: 29377353 DOI: 10.1002/ejp.1186] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/27/2017] [Indexed: 11/09/2022]
Abstract
BACKGROUND Dopamine (DA) is thought to be important to local hippocampal networks integrity during spatial working memory (sWM) processing. Chronic pain may contribute to deficient dopaminergic signalling, which may in turn affect cognition. However, the neural mechanisms that determine this impairment are poorly understood. Here, we evaluated whether the sWM impairment characteristic of animal models of chronic pain is dependent on DA D2 receptor (D2r) activity. METHODS To address this issue, we implanted multichannel arrays of electrodes in the dorsal and ventral hippocampal CA1 field (dvCA1) of rats and recorded the neuronal activity during a classical delayed food-reinforced T-maze sWM task. Within-subject behavioural performance and patterns of dorsoventral neural activity were assessed before and after the onset of persistent neuropathic pain using the spared nerve injury (SNI) model. RESULTS Our results show that the peripheral nerve lesion caused a disruption in sWM and hippocampus spike activity and that disruption was maximized by the systemic administration of the D2r antagonist raclopride. These deficits are strictly correlated with a selective disruption of hippocampal theta-oscillations. Particularly, we found a significant decrease in intrahippocampal CA1 field connectivity level. CONCLUSIONS Together, these results suggest that disruption of the dopaminergic balance in the intrahippocampal networks may be important for the development of cognitive deficits experienced during painful conditions. SIGNIFICANCE This study provides new insights into the role of D2r in the manifestation of pain-related sWM deficits. Our findings support that selective blockade of D2r produces a significant decrease in intrahippocampal connectivity mediated by theta-oscillations, and amplifies pain-related sWM deficits. These results suggest that further characterization of intrahippocampal dopaminergic modulation may be clinically relevant for the understanding of cognitive impairments that accompanies nociceptive stressful conditions.
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Affiliation(s)
- H Cardoso-Cruz
- Departamento de Biomedicina - Unidade de Biologia Experimental, Faculdade de Medicina, Centro de investigação Médica, Universidade do Porto, Porto, Portugal.,I3S - Instituto de Investigação e Inovação em Saúde & IBMC - Instituto de Biologia Molecular e Celular, Pain Research Group, Universidade do Porto, Porto, Portugal
| | - M Dourado
- Departamento de Biomedicina - Unidade de Biologia Experimental, Faculdade de Medicina, Centro de investigação Médica, Universidade do Porto, Porto, Portugal.,I3S - Instituto de Investigação e Inovação em Saúde & IBMC - Instituto de Biologia Molecular e Celular, Pain Research Group, Universidade do Porto, Porto, Portugal.,PDN - Programa Doutoral em Neurociências, Faculdade de Medicina, Universidade do Porto, Porto, Portugal
| | - C Monteiro
- Departamento de Biomedicina - Unidade de Biologia Experimental, Faculdade de Medicina, Centro de investigação Médica, Universidade do Porto, Porto, Portugal.,I3S - Instituto de Investigação e Inovação em Saúde & IBMC - Instituto de Biologia Molecular e Celular, Pain Research Group, Universidade do Porto, Porto, Portugal
| | - V Galhardo
- Departamento de Biomedicina - Unidade de Biologia Experimental, Faculdade de Medicina, Centro de investigação Médica, Universidade do Porto, Porto, Portugal.,I3S - Instituto de Investigação e Inovação em Saúde & IBMC - Instituto de Biologia Molecular e Celular, Pain Research Group, Universidade do Porto, Porto, Portugal
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Watanabe M, Sugiura Y, Sugiyama E, Narita M, Navratilova E, Kondo T, Uchiyama N, Yamanaka A, Kuzumaki N, Porreca F, Narita M. Extracellular N-acetylaspartylglutamate released in the nucleus accumbens modulates the pain sensation: Analysis using a microdialysis/mass spectrometry integrated system. Mol Pain 2018; 14:1744806918754934. [PMID: 29310499 PMCID: PMC5813845 DOI: 10.1177/1744806918754934] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Various small molecules act as neurotransmitters and orchestrate neural communication. Growing evidence suggests that not only classical neurotransmitters but also several small molecules, including amino acid derivatives, modulate synaptic transmission. As conditions of acute and chronic pain alter neuronal excitability in the nucleus accumbens, we hypothesized that small molecules released in the nucleus accumbens might play important roles in modulating the pain sensation. However, it is not easy to identify possible pain modulators owing to the absence of a method for comprehensively measuring extracellular small molecules in the brain. In this study, through the use of an emerging metabolomics technique, namely ion chromatography coupled with high-resolution mass spectrometry, we simultaneously analyzed the dynamics of more than 60 small molecules in brain fluids collected by microdialysis, under both the application of pain stimuli and the administration of analgesics. We identified N-acetylaspartylglutamate as a potential pain modulator that is endogenously released in the nucleus accumbens. Infusion of N-acetylaspartylglutamate into the nucleus accumbens significantly attenuated the pain induced by the activation of sensory nerves through optical stimulation. These findings suggest that N-acetylaspartylglutamate released in the nucleus accumbens could modulate pain sensation.
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Affiliation(s)
- Moe Watanabe
- 1 Department of Pharmacology, Hoshi University School of Pharmacy and Pharmaceutical Sciences, Tokyo, Japan
| | - Yuki Sugiura
- 2 Department of Biochemistry, Keio University School of Medicine, Tokyo, Japan
| | - Eiji Sugiyama
- 2 Department of Biochemistry, Keio University School of Medicine, Tokyo, Japan
| | - Michiko Narita
- 1 Department of Pharmacology, Hoshi University School of Pharmacy and Pharmaceutical Sciences, Tokyo, Japan
| | - Edita Navratilova
- 3 Department of Pharmacology, Arizona Health Sciences Center, University of Arizona, Tucson, AZ, USA
| | - Takashige Kondo
- 1 Department of Pharmacology, Hoshi University School of Pharmacy and Pharmaceutical Sciences, Tokyo, Japan
| | - Naohiko Uchiyama
- 1 Department of Pharmacology, Hoshi University School of Pharmacy and Pharmaceutical Sciences, Tokyo, Japan
| | - Akihiro Yamanaka
- 4 Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Naoko Kuzumaki
- 1 Department of Pharmacology, Hoshi University School of Pharmacy and Pharmaceutical Sciences, Tokyo, Japan
| | - Frank Porreca
- 3 Department of Pharmacology, Arizona Health Sciences Center, University of Arizona, Tucson, AZ, USA
| | - Minoru Narita
- 1 Department of Pharmacology, Hoshi University School of Pharmacy and Pharmaceutical Sciences, Tokyo, Japan.,5 Life Science Tokyo Advanced Research Center (L-StaR), Hoshi University School of Pharmacy and Pharmaceutical Sciences, Tokyo, Japan
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Schafer SM, Geuter S, Wager TD. Mechanisms of placebo analgesia: A dual-process model informed by insights from cross-species comparisons. Prog Neurobiol 2018; 160:101-122. [PMID: 29108801 PMCID: PMC5747994 DOI: 10.1016/j.pneurobio.2017.10.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 10/24/2017] [Accepted: 10/28/2017] [Indexed: 12/19/2022]
Abstract
Placebo treatments are pharmacologically inert, but are known to alleviate symptoms across a variety of clinical conditions. Associative learning and cognitive expectations both play important roles in placebo responses, however we are just beginning to understand how interactions between these processes lead to powerful effects. Here, we review the psychological principles underlying placebo effects and our current understanding of their brain bases, focusing on studies demonstrating both the importance of cognitive expectations and those that demonstrate expectancy-independent associative learning. To account for both forms of placebo analgesia, we propose a dual-process model in which flexible, contextually driven cognitive schemas and attributions guide associative learning processes that produce stable, long-term placebo effects. According to this model, the placebo-induction paradigms with the most powerful effects are those that combine reinforcement (e.g., the experience of reduced pain after placebo treatment) with suggestions and context cues that disambiguate learning by attributing perceived benefit to the placebo. Using this model as a conceptual scaffold, we review and compare neurobiological systems identified in both human studies of placebo analgesia and behavioral pain modulation in rodents. We identify substantial overlap between the circuits involved in human placebo analgesia and those that mediate multiple forms of context-based modulation of pain behavior in rodents, including forebrain-brainstem pathways and opioid and cannabinoid systems in particular. This overlap suggests that placebo effects are part of a set of adaptive mechanisms for shaping nociceptive signaling based on its information value and anticipated optimal response in a given behavioral context.
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Affiliation(s)
- Scott M Schafer
- Department of Psychology and Neuroscience, University of Colorado, 345 UCB, Boulder, CO 80309, USA
| | - Stephan Geuter
- Department of Psychology and Neuroscience, University of Colorado, 345 UCB, Boulder, CO 80309, USA; Institute of Cognitive Science, University of Colorado Boulder, 344 UCB, Boulder, CO 80309, USA; Department of Biostatistics, Johns Hopkins University, 615 N Wolfe St, Baltimore, MD 21205, USA
| | - Tor D Wager
- Department of Psychology and Neuroscience, University of Colorado, 345 UCB, Boulder, CO 80309, USA; Institute of Cognitive Science, University of Colorado Boulder, 344 UCB, Boulder, CO 80309, USA.
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Role of orexin-2 receptors in the nucleus accumbens in antinociception induced by carbachol stimulation of the lateral hypothalamus in formalin test. Behav Pharmacol 2017; 27:431-8. [PMID: 26871404 DOI: 10.1097/fbp.0000000000000216] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Orexins, which are mainly produced by orexin-expressing neurons in the lateral hypothalamus (LH), play an important role in pain modulation. Previously, it has been established that the nucleus accumbens (NAc) is involved in the modulation of formalin-induced nociceptive responses, a model of tonic pain. In this study, the role of intra-accumbal orexin-2 receptors (OX2rs) in the mediation of formalin-induced pain was investigated. A volume of 0.5 μl of 10, 20, and 40 nmol/l solutions of TCS OX2 29, an OX2r antagonist, were unilaterally microinjected into the NAc 5 min before an intra-LH carbachol microinjection (0.5 μl of 250 nmol/l solution). After 5 min, animals received a subcutaneous injection of formalin 2.5% (50 μl) into the hind paw. Pain-related behaviors were assessed at 5 min intervals during a 60-min test period. The findings showed that TCS OX2 29 administration dose dependently blocked carbachol-induced antinociception during both phases of formalin-induced pain. The antianalgesic effect of TCS OX2 29 was greater during the late phase compared with the early phase. These observations suggest that the NAc, as a part of a descending pain-modulatory circuitry, partially mediates LH-induced analgesia in the formalin test through recruitment of OX2rs. This makes the orexinergic system a good potential therapeutic target in the control of persistent inflammatory pain.
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Dopaminergic tone does not influence pain levels during placebo interventions in patients with chronic neuropathic pain. Pain 2017; 159:261-272. [DOI: 10.1097/j.pain.0000000000001089] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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58
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Zhang H, Qian YL, Li C, Liu D, Wang L, Wang XY, Liu MJ, Liu H, Zhang S, Guo XY, Yang JX, Ding HL, Koo JW, Mouzon E, Deisseroth K, Nestler EJ, Zachariou V, Han MH, Cao JL. Brain-Derived Neurotrophic Factor in the Mesolimbic Reward Circuitry Mediates Nociception in Chronic Neuropathic Pain. Biol Psychiatry 2017; 82:608-618. [PMID: 28390647 PMCID: PMC5788809 DOI: 10.1016/j.biopsych.2017.02.1180] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 01/18/2017] [Accepted: 02/21/2017] [Indexed: 12/15/2022]
Abstract
BACKGROUND The mesolimbic reward system plays a critical role in modulating nociception; however, its underlying molecular, cellular, and neural circuitry mechanisms remain unknown. METHODS Chronic constrictive injury (CCI) of the sciatic nerve was used to model neuropathic pain. Projection-specific in vitro recordings in mouse brain slices and in vivo recordings from anesthetized animals were used to measure firing of dopaminergic neurons in the ventral tegmental area (VTA). The role of VTA-nucleus accumbens (NAc) circuitry in nociceptive regulation was assessed using optogenetic and pharmacological manipulations, and the underlying molecular mechanisms were investigated by Western blotting, enzyme-linked immunosorbent assays, and conditional knockdown techniques. RESULTS c-Fos expression in and firing of contralateral VTA-NAc dopaminergic neurons were elevated in CCI mice, and optogenetic inhibition of these neurons reversed CCI-induced thermal hyperalgesia. CCI increased the expression of brain-derived neurotrophic factor (BDNF) protein but not messenger RNA in the contralateral NAc. This increase was reversed by pharmacological inhibition of VTA dopaminergic neuron activity, which induced an antinociceptive effect that was neutralized by injecting exogenous BDNF into the NAc. Moreover, inhibition of BDNF synthesis in the VTA with anisomycin or selective knockdown of BDNF in the VTA-NAc pathway was antinociceptive in CCI mice. CONCLUSIONS These results reveal a novel mechanism of nociceptive modulation in the mesolimbic reward circuitry and provide new insight into the neural circuits involved in the processing of nociceptive information.
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Affiliation(s)
- Hongxing Zhang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China,Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China,Department of Pharmacological Sciences, Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, New York 10029-6574, USA
| | - Yi-Ling Qian
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China,Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Chen Li
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China,Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Di Liu
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China,Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Lei Wang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China,Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Xiao-Yi Wang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China,Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Mei-Jun Liu
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China,Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - He Liu
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China,Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China,Department of Anesthesiology, the Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu 221002, China
| | - Song Zhang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China,Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Xiao-Yun Guo
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China,Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Jun-Xia Yang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China,Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Hai-Lei Ding
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China,Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Ja Wook Koo
- Fishberg Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029-6574, USA
| | - Ezekiell Mouzon
- Department of Pharmacological Sciences, Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, New York 10029-6574, USA
| | - Karl Deisseroth
- Department of Bioengineering, Stanford University, Stanford, California 94305, USA
| | - Eric J Nestler
- Fishberg Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029-6574, USA
| | - Venetia Zachariou
- Fishberg Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029-6574, USA
| | - Ming-Hu Han
- Department of Pharmacological Sciences, Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, New York 10029-6574, USA,Fishberg Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029-6574, USA
| | - Jun-Li Cao
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou, China; Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, Xuzhou Medical University, Xuzhou, China; Department of Anesthesiology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China.
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Sousa FS, Anversa RG, Birmann PT, de Souza MN, Balaguez R, Alves D, Luchese C, Wilhelm EA, Savegnago L. Contribution of dopaminergic and noradrenergic systems in the antinociceptive effect of α-(phenylalanyl) acetophenone. Pharmacol Rep 2017. [DOI: 10.1016/j.pharep.2017.03.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Nucleus accumbens mediates the pronociceptive effect of sleep deprivation: the role of adenosine A2A and dopamine D2 receptors. Pain 2017; 159:75-84. [DOI: 10.1097/j.pain.0000000000001066] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Kissel CL, Kovács KJ, Larson AA. Evidence for the modulation of nociception in mice by central mast cells. Eur J Pain 2017; 21:1743-1755. [PMID: 28722336 DOI: 10.1002/ejp.1086] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/21/2017] [Indexed: 12/24/2022]
Abstract
BACKGROUND Hyperalgesia that develops following nerve ligation corresponds temporally and in magnitude with the number of thalamic mast cells located contralateral to the ligature. We tested the possibility that mast cells modulate nociception centrally, similar to their role in the periphery. METHODS We examined the central effect of two hyperalgesic compounds that induce mast cell degranulation and of stabilized mast cells using cromolyn. RESULTS Thermal hyperalgesia (tail flick) induced by nerve growth factor (NGF, a neurotrophic compound) and mechanical hyperalgesia (von Frey) induced by dynorphin A (1-17) (opioid compound) each correlated with the per cent of thalamic mast cells that were degranulated. Degranulation of these mast cells by the central injection of compound 48/80, devoid of neurotrophic or opioid activity, was sufficient to recapitulate thermal hyperalgesia. Stabilization of mast cells by central injections of cromolyn produced no analgesic effect on baseline tail flick or von Frey fibre sensitivity, but inhibited thermal hyperalgesia produced by compound 48/80 and tactile hyperalgesia induced by dynorphin and by Freund's complete adjuvant. Finally, chemical nociception produced by the direct activation of nociceptors by formalin (phase I) was not inhibited by centrally injected cromolyn whereas chemical nociception dependent on central sensitization (formalin-phase II and acetic acid-induced abdominal stretches) was. CONCLUSIONS These convergent lines of evidence suggest that degranulation of centrally located mast cells sensitizes central nociceptive pathways leading to hyperalgesia and tonic chemical sensitivity. SIGNIFICANCE Hyperalgesia induced by spinal nerve ligation corresponds temporally and in magnitude with degranulation of thalamic mast cells. Here, we provide evidence that hyperalgesia induced by NGF, formalin and dynorphin also may depend on mast cell degranulation in the CNS whereas cromolyn, a mast cell stabilizer, blocks these effects in mice.
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Affiliation(s)
- C L Kissel
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Minneapolis, MN, USA
| | - K J Kovács
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Minneapolis, MN, USA
| | - A A Larson
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Minneapolis, MN, USA
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Gandolfi M, Geroin C, Antonini A, Smania N, Tinazzi M. Understanding and Treating Pain Syndromes in Parkinson's Disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2017; 134:827-858. [PMID: 28805585 DOI: 10.1016/bs.irn.2017.05.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Pain affects many people with Parkinson's disease (PD) and diminishes their quality of life. Different types of pain have been described, but their related pathophysiological mechanisms remain unclear. The aim of this chapter is to provide movement disorders specialists an update about the pathophysiology of pain and a practical guide for the management of pain syndromes in clinical practice. This chapter reviews current knowledge on the pathophysiological mechanisms of sensory changes and pain in PD, as well as assessment and treatment procedures to manage these symptoms. In summary, changes in peripheral and central pain processing have been demonstrated in PD patients. A decrease in pain threshold and tolerance to several stimuli, a reduced nociceptive withdrawal reflex, a reduced pain threshold, and abnormal pain-induced activation in cortical pain-related areas have been reported. There is no direct association between improvement of motor symptoms and sensory/pain changes, suggesting that motor and nonmotor symptoms do not inevitably share the same mechanisms. Special care in pain assessment in PD is warranted by the specific pathophysiological aspects and the complexity of motor and nonmotor symptoms associated with pain symptoms. Rehabilitation may represent a valid option to manage pain syndromes in PD. However, further research in this field is needed. An integrated approach to pain involving a multidisciplinary team of medical specialists and rehabilitation experts should allow a comprehensive approach to pain in PD.
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Affiliation(s)
- Marialuisa Gandolfi
- Neuromotor and Cognitive Rehabilitation Research Center (CRRNC), University of Verona, Verona, Italy; Neurorehabilitation Unit, Azienda Ospedaliera Universitaria Integrata, Verona, Italy
| | - Christian Geroin
- Neuromotor and Cognitive Rehabilitation Research Center (CRRNC), University of Verona, Verona, Italy
| | - Angelo Antonini
- University of Padua and Hospital San Camillo IRCCS, Venice, Italy
| | - Nicola Smania
- Neuromotor and Cognitive Rehabilitation Research Center (CRRNC), University of Verona, Verona, Italy; Neurorehabilitation Unit, Azienda Ospedaliera Universitaria Integrata, Verona, Italy
| | - Michele Tinazzi
- Neurology Unit, Movement Disorders Division, University of Verona, Verona, Italy.
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Reichard RA, Subramanian S, Desta MT, Sura T, Becker ML, Ghobadi CW, Parsley KP, Zahm DS. Abundant collateralization of temporal lobe projections to the accumbens, bed nucleus of stria terminalis, central amygdala and lateral septum. Brain Struct Funct 2017; 222:1971-1988. [PMID: 27704219 PMCID: PMC5378696 DOI: 10.1007/s00429-016-1321-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 09/28/2016] [Indexed: 10/20/2022]
Abstract
Behavioral flexibility is subserved in part by outputs from the cerebral cortex to telencephalic subcortical structures. In our earlier evaluation of the organization of the cortical-subcortical output system (Reynolds and Zahm, J Neurosci 25:11757-11767, 2005), retrograde double-labeling was evaluated in the prefrontal cortex following tracer injections into pairs of the following subcortical telencephalic structures: caudate-putamen, core and shell of the accumbens (Acb), bed nucleus of stria terminalis (BST) and central nucleus of the amygdala (CeA). The present study was done to assess patterns of retrograde labeling in the temporal lobe after similar paired tracer injections into most of the same telencephalic structures plus the lateral septum (LS). In contrast to the modest double-labeling observed in the prefrontal cortex in the previous study, up to 60-80 % of neurons in the basal and accessory basal amygdaloid nuclei and amygdalopiriform transition area exhibited double-labeling in the present study. The most abundant double-labeling was generated by paired injections into structures affiliated with the extended amygdala, including the CeA, BST and Acb shell. Injections pairing the Acb core with the BST or CeA produced significantly fewer double-labeled neurons. The ventral subiculum exhibited modest amounts of double-labeling associated with paired injections into the Acb, BST, CeA and LS. The results raise the issue of how an extraordinarily collateralized output from the temporal lobe may contribute to behavioral flexibility.
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Affiliation(s)
- Rhett A Reichard
- Department of Pharmacological and Physiological Science, School of Medicine, Saint Louis University, 1402 S, Grand Blvd., Saint Louis, MO, 63104, USA
| | - Suriya Subramanian
- Department of Pharmacological and Physiological Science, School of Medicine, Saint Louis University, 1402 S, Grand Blvd., Saint Louis, MO, 63104, USA
| | - Mikiyas T Desta
- Department of Pharmacological and Physiological Science, School of Medicine, Saint Louis University, 1402 S, Grand Blvd., Saint Louis, MO, 63104, USA
| | - Tej Sura
- Department of Pharmacological and Physiological Science, School of Medicine, Saint Louis University, 1402 S, Grand Blvd., Saint Louis, MO, 63104, USA
| | - Mary L Becker
- Department of Pharmacological and Physiological Science, School of Medicine, Saint Louis University, 1402 S, Grand Blvd., Saint Louis, MO, 63104, USA
| | - Comeron W Ghobadi
- Department of Pharmacological and Physiological Science, School of Medicine, Saint Louis University, 1402 S, Grand Blvd., Saint Louis, MO, 63104, USA
| | - Kenneth P Parsley
- Department of Pharmacological and Physiological Science, School of Medicine, Saint Louis University, 1402 S, Grand Blvd., Saint Louis, MO, 63104, USA
| | - Daniel S Zahm
- Department of Pharmacological and Physiological Science, School of Medicine, Saint Louis University, 1402 S, Grand Blvd., Saint Louis, MO, 63104, USA.
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Lazenka MF, Freitas KC, Henck S, Negus SS. Relief of Pain-Depressed Behavior in Rats by Activation of D1-Like Dopamine Receptors. J Pharmacol Exp Ther 2017; 362:14-23. [PMID: 28411257 DOI: 10.1124/jpet.117.240796] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 04/13/2017] [Indexed: 12/11/2022] Open
Abstract
Clinically significant pain often includes a decrease in both behavior and mesolimbic dopamine signaling. Indirect and/or direct dopamine receptor agonists may alleviate pain-related behavioral depression. To test this hypothesis, the present study compared effects of indirect and direct dopamine agonists in a preclinical assay of pain-depressed operant responding. Male Sprague-Dawley rats with chronic indwelling microelectrodes in the medial forebrain bundle were trained in an intracranial self-stimulation (ICSS) procedure to press a lever for pulses of electrical brain stimulation. Intraperitoneal injection of dilute lactic acid served as an acute noxious stimulus to depress ICSS. Intraperitoneal lactic acid-induced depression of ICSS was dose-dependently blocked by the dopamine transporter inhibitor methylphenidate and the D1-selective agonist SKF82958, but not by the D2/3-selective agonists quinpirole, pramipexole, or sumanirole. The antinociceptive effects of methylphenidate and SKF82958 were blocked by the D1-selective antagonist SCH39166. Acid-induced stimulation of a stretching response was evaluated in separate groups of rats, but all agonists decreased acid-stimulated stretching, and antagonism experiments were inconclusive due to direct effects of the antagonists when administered alone. Taken together, these results suggest that D1-receptor stimulation is both sufficient to block acid-induced depression of ICSS and necessary for methylphenidate antinociception in this procedure. Conversely, D2/3-receptor stimulation is not sufficient to relieve pain-depressed behavior. These results support the hypothesis that pain-related depression of dopamine D1 receptor signaling contributes to pain-related depression of behavior in rats. Additionally, these results support further consideration of indirect dopamine agonists and direct D1 receptor agonists as candidate treatments for pain-related behavioral depression.
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Affiliation(s)
- Matthew F Lazenka
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia
| | - Kelen C Freitas
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia
| | - Sydney Henck
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia
| | - S Stevens Negus
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia
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Siahposht-Khachaki A, Pourreza P, Ezzatpanah S, Haghparast A. Nucleus accumbens dopamine receptors mediate hypothalamus-induced antinociception in the rat formalin test. Eur J Pain 2017; 21:1285-1294. [DOI: 10.1002/ejp.1029] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/30/2017] [Indexed: 12/15/2022]
Affiliation(s)
- A. Siahposht-Khachaki
- Department of Physiology and Pharmacology; Mazandaran University of Medical Sciences, Ramsar International Branch; Sari Iran
| | - P. Pourreza
- Neuroscience Research Center, School of Medicine; Shahid Beheshti University of Medical Sciences; Tehran Iran
| | - S. Ezzatpanah
- Neuroscience Research Center, School of Medicine; Shahid Beheshti University of Medical Sciences; Tehran Iran
| | - A. Haghparast
- Neuroscience Research Center, School of Medicine; Shahid Beheshti University of Medical Sciences; Tehran Iran
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Mesolimbic dopamine signaling in acute and chronic pain: implications for motivation, analgesia, and addiction. Pain 2017; 157:1194-1198. [PMID: 26797678 PMCID: PMC4866581 DOI: 10.1097/j.pain.0000000000000494] [Citation(s) in RCA: 153] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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YAMAMOTOVÁ A, FRICOVÁ J, ROKYTA R, ŠLAMBEROVÁ R. The Effect of Combined Treatment of Opioids With Methylphenidate on Nociception in Rats and Pain in Human. Physiol Res 2016; 65:S567-S575. [DOI: 10.33549/physiolres.933535] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Methylphenidate hydrochloride (MPH/Ritalin) is a stimulant used for off-label management of cancer-related fatigue and sedation; however, its use in pain treatment is still relatively rare. This study 1) compares the antinociceptive effect of MPH and its combination with morphine (MOR) in adult male Wistar rats after a single administration of MPH, MOR or their combination, and 2) compares the analgesic effects of opioids and Ritalin combined therapy with opioid monotherapy in patients with cancer pain. To objectively assess physical activity during a three-week monitoring period, patients were equipped with Actiwatch Score Actigraph. Patients performed daily evaluations of pain intensity and frequency, and the extent to which pain interfered with their daily life. Our research with rats supports the evidence that MPH in lower doses has the ability to enhance the analgesic properties of morphine when the two drugs are used in combination. Results from the patient arm of our study found that short-term treatment had no significant effect on intensity or frequency of pain, however it decreased the overall burden of pain; the combined treatment of opioid and Ritalin also showed anti-sedation effects and resulted in mild improvement in one of our patient’s quality of life.
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Neelakantan H, Ward SJ, Walker EA. Effects of paclitaxel on mechanical sensitivity and morphine reward in male and female C57Bl6 mice. Exp Clin Psychopharmacol 2016; 24:485-495. [PMID: 27929349 PMCID: PMC5157702 DOI: 10.1037/pha0000097] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This study evaluated the hypothesis that a paclitaxel treatment regimen sufficient to produce mechanical allodynia would alter sensitivities of male and female mice to the conditioned rewarding and reinforcing effects of morphine. Saline or paclitaxel were administered on Days 1, 3, 5, and 7 in male and female C57Bl/6 mice to induce morphine-reversible mechanical allodynia as measured by the Von Frey filament test. Paclitaxel treatment did not change sensitivity to morphine conditioned place preference (CPP) relative to saline treatment in either male or female mice. Morphine produced peak self-administration under a fixed ratio-1 (FR1) schedule of reinforcement for 0.03 mg/kg morphine per infusion in female mice and 0.1 mg/kg morphine per infusion in male mice. During the progressive ratio experiments, saline treatment in male mice decreased the number of morphine infusions for 12 days whereas the paclitaxel-treated male mice maintained responding for morphine similar to baseline levels during the same time period. However, paclitaxel did not have an overall effect on the reinforcing efficacy of morphine assessed over a limited dose range during the course of the repeated self-administration. These results suggest that the reward-related behavioral effects of morphine are overall not robustly altered by the presence of paclitaxel treatment under the current dosing regimen, with the exception of maintaining a small yet significant higher baseline than saline treatment during the development of allodynia in male mice. (PsycINFO Database Record
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Affiliation(s)
| | | | - Ellen Ann Walker
- Department of Pharmaceutical Sciences & Center for Substance Abuse Research, Temple University
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The effect of forced swim stress on morphine sensitization: Involvement of D1/D2-like dopamine receptors within the nucleus accumbens. Prog Neuropsychopharmacol Biol Psychiatry 2016; 70:92-9. [PMID: 27235796 DOI: 10.1016/j.pnpbp.2016.05.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 05/17/2016] [Accepted: 05/24/2016] [Indexed: 11/21/2022]
Abstract
Nucleus accumbens (NAc) plays an essential role in morphine sensitization and suppression of pain. Repeated exposure to stress and morphine increases dopamine release in the NAc and may lead to morphine sensitization. This study was carried out in order to investigate the effect of forced swim stress (FSS), as a predominantly physical stressor and morphine on the development of morphine sensitization; focusing on the function of D1/D2-like dopamine receptors in the NAc in morphine sensitization. Eighty-five adult male Wistar rats were bilaterally implanted with cannulae in the NAc and various doses of SCH-23390 (0.125, 0.25, 1 and 4μg/0.5μl/NAc) as a D1 receptor antagonist and sulpiride (0.25, 1 and 4μg/0.5μl/NAc) as a D2 receptor antagonist were microinjected into the NAc, during a sensitization period of 3days, 5min before the induction of FSS. After 10min, animals received subcutaneous morphine injection (1mg/kg). The procedure was followed by 5days free of antagonist, morphine and stress; thereafter on the 9th day, the nociceptive response was evaluated by tail-flick test. The results revealed that the microinjection of sulpiride (at 1 and 4μg/0.5μl/NAc) or SCH-23390 (at 0.25, 1 and 4μg/0.5μl/NAc) prior to FSS and morphine disrupts the antinociceptive effects of morphine and morphine sensitization. Our findings suggest that FSS can potentiate the effect of morphine and causes morphine sensitization which induces antinociception.
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Reward deficiency and anti-reward in pain chronification. Neurosci Biobehav Rev 2016; 68:282-297. [DOI: 10.1016/j.neubiorev.2016.05.033] [Citation(s) in RCA: 132] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 05/26/2016] [Accepted: 05/27/2016] [Indexed: 12/12/2022]
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Kim DY, Chae JW, Lim CH, Heo BH, Park KS, Lee HG, Choi JI, Yoon MH, Kim WM. The Role of Spinal Dopaminergic Transmission in the Analgesic Effect of Nefopam on Rat Inflammatory Pain. Korean J Pain 2016; 29:164-71. [PMID: 27413481 PMCID: PMC4942644 DOI: 10.3344/kjp.2016.29.3.164] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 06/07/2016] [Accepted: 06/14/2016] [Indexed: 02/07/2023] Open
Abstract
Background Nefopam has been known as an inhibitor of the reuptake of monoamines, and the noradrenergic and/or serotonergic system has been focused on as a mechanism of its analgesic action. Here we investigated the role of the spinal dopaminergic neurotransmission in the antinociceptive effect of nefopam administered intravenously or intrathecally. Methods The effects of intravenously and intrathecally administered nefopam were examined using the rat formalin test. Then we performed a microdialysis study to confirm the change of extracellular dopamine concentration in the spinal dorsal horn by nefopam. To determine whether the changes of dopamine level are associated with the nefopam analgesia, its mechanism was investigated pharmacologically via pretreatment with sulpiride, a dopaminergic D2 receptor antagonist. Results When nefopam was administered intravenously the flinching responses in phase I of the formalin test were decreased, but not those in phase II of the formalin test were decreased. Intrathecally injected nefopam reduced the flinching responses in both phases of the formalin test in a dose dependent manner. Microdialysis study revealed a significant increase of the level of dopamine in the spinal cord by intrathecally administered nefopam (about 3.8 fold the baseline value) but not by that administered intravenously. The analgesic effects of intrathecally injected nefopam were not affected by pretreatment with sulpiride, and neither were those of the intravenous nefopam. Conclusions Both the intravenously and intrathecally administered nefopam effectively relieved inflammatory pain in rats. Nefopam may act as an inhibitor of dopamine reuptake when delivered into the spinal cord. However, the analgesic mechanism of nefopam may not involve the dopaminergic transmission at the spinal level.
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Affiliation(s)
- Do Yun Kim
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, Gwangju, Korea
| | - Joo Wung Chae
- Center for Creative Biomedical Scientists, Chonnam National University Medical School, Gwangju, Korea
| | - Chang Hun Lim
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, Gwangju, Korea
| | - Bong Ha Heo
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, Gwangju, Korea
| | - Keun Suk Park
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, Gwangju, Korea
| | - Hyung Gon Lee
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, Gwangju, Korea
| | - Jeong Il Choi
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, Gwangju, Korea
| | - Myung Ha Yoon
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, Gwangju, Korea
| | - Woong Mo Kim
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, Gwangju, Korea.; Center for Creative Biomedical Scientists, Chonnam National University Medical School, Gwangju, Korea
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Faramarzi G, Zendehdel M, Haghparast A. D1- and D2-like dopamine receptors within the nucleus accumbens contribute to stress-induced analgesia in formalin-related pain behaviours in rats. Eur J Pain 2016; 20:1423-32. [PMID: 27271035 DOI: 10.1002/ejp.865] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/27/2016] [Indexed: 11/07/2022]
Abstract
BACKGROUND Stressful experiences can produce analgesia, termed stress-induced analgesia (SIA). Meanwhile, it has been widely established that the mesolimbic dopamine pathway and nucleus accumbens (NAc) have a profound role in pain modulation. In this study, we examined the role of accumbal dopamine receptors in antinociception caused by forced swim stress (FSS) in order to understand more about the function of these receptors within the NAc in FSS-induced analgesia. METHOD Stereotaxic surgery was unilaterally performed on adult male Wistar rats weighing 230-250 g (some on the left and some on the right side of the midline). Two supergroups were microinjected into the NAc with a D1-like dopamine receptor antagonist, SCH-23390, at doses of 0.25, 1 and 4 μg/0.5 μl saline per rat or Sulpiride as a D2-like dopamine receptor antagonist at the same doses [0.25, 1 and 4 μg/0.5 μl dimethyl sulfoxide (DMSO) per rat]; while their controls just received intra-accumbal saline or DMSO at 0.5 μl, respectively. The formalin test was performed after rats were subjected to FSS (6 min, 25 ± 1 °C) to assess pain-related behaviours. RESULTS The results demonstrated that intra-accumbal infusions of SCH-23390 and Sulpiride dose-dependently reduced FSS-induced antinociception in both phases of the formalin test. However, the percentage decrease in area under the curve (AUC) values calculated for treatment groups compared to formalin-control group was more significant in the late phase than the early phase. CONCLUSION Our findings suggest that D1- and D2-like dopamine receptors in the NAc are involved in stress-induced antinociceptive behaviours in the formalin test as an animal model of persistent inflammatory pain. WHAT DOES THIS STUDY ADD Forced swim stress (FSS) induces the antinociception in both phases of formalin test. Blockade of accumbal dopamine receptors attenuate the antinociception induced by FSS. Stress-induced analgesia is dose-dependently reduced by dopamine receptor antagonists in both phases, although it is more prominent during the late phase.
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Affiliation(s)
- G Faramarzi
- Department of Physiology, Faculty of Veterinary Medicine, University of Tehran, Iran
| | - M Zendehdel
- Department of Physiology, Faculty of Veterinary Medicine, University of Tehran, Iran
| | - A Haghparast
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. ,
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Markedly Reduced Thermal Pain Perception in a Schizoaffective Patient with Tardive Dyskinesia. Case Rep Psychiatry 2016; 2016:8702483. [PMID: 27144045 PMCID: PMC4842046 DOI: 10.1155/2016/8702483] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 03/31/2016] [Indexed: 11/25/2022] Open
Abstract
Several case reports have described stories of schizophrenia patients reporting no discomfort in response to several medical conditions which normally elicit pain. Comparatively, experimental studies performed on pain perception in schizophrenia have not documented hypoalgesic responses that are as frank as those reported in these clinical cases. Here, we report the case of a female patient with schizoaffective disorder, who displayed markedly reduced pain perception during an experimental heat pain paradigm. Compared to a large group of healthy volunteers that we tested in 3 previous studies using the same psychophysical procedure, the experimental temperature required to induce moderate pain was radically increased in this patient (z-score = 3.6). The patient had mild psychiatric symptoms and had insight into her symptoms. She had drug-induced dyskinetic symptoms. This case report illustrates that it is possible to observe marked reductions in pain perception in schizophrenia patients tested in experimental settings but that the phenomenon is relatively rare. Regardless of the exact nature of pain indifference in schizophrenia, it can delay diagnosis and treatment of medical problems in these patients. Future studies in the field will need to pay attention to drug-induced extrapyramidal symptoms.
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Ezzatpanah S, Babapour V, Haghparast A. Differential contribution of orexin receptors within the ventral tegmental area to modulation of persistent inflammatory pain. Eur J Pain 2016; 20:1090-101. [DOI: 10.1002/ejp.833] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/22/2015] [Indexed: 11/06/2022]
Affiliation(s)
- S. Ezzatpanah
- Department of Basic Sciences; Faculty of Veterinary Medicine; University of Tehran; Iran
| | - V. Babapour
- Department of Basic Sciences; Faculty of Veterinary Medicine; University of Tehran; Iran
| | - A. Haghparast
- Neuroscience Research Center; Shahid Beheshti University of Medical Sciences; Tehran Iran
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Kandre D, Banwari G, Sharma P. Comorbid Functional Shoulder Pain and Zolpidem Dependence Treated with Pramipexole. Indian J Psychol Med 2015; 37:443-5. [PMID: 26702179 PMCID: PMC4676213 DOI: 10.4103/0253-7176.168591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Pramipexole is a dopamine agonist with higher affinity for D3 receptors. Treatment with pramipexole in clinical conditions such as restless legs syndrome, fibromyalgia, and parkinsonism has been found to significantly improve measures of pain and sleep along with the other symptoms. There is no research data available that explores the usefulness of pramipexole in somatoform/functional pain syndromes. We report a case of a 65-year-old male with bilateral functional shoulder pain associated with insomnia and zolpidem dependence effectively treated with pramipexole.
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Affiliation(s)
- Dhiraj Kandre
- Department of Psychiatry, Smt. N.H.L. Municipal Medical College and Sheth V.S. General Hospital, Ahmedabad, Gujarat, India
| | - Girish Banwari
- Department of Psychiatry, Smt. N.H.L. Municipal Medical College and Sheth V.S. General Hospital, Ahmedabad, Gujarat, India
| | - Prateek Sharma
- Department of Psychiatry, Smt. N.H.L. Municipal Medical College and Sheth V.S. General Hospital, Ahmedabad, Gujarat, India
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Moradi M, Yazdanian M, Haghparast A. Role of dopamine D2-like receptors within the ventral tegmental area and nucleus accumbens in antinociception induced by lateral hypothalamus stimulation. Behav Brain Res 2015; 292:508-14. [DOI: 10.1016/j.bbr.2015.07.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 06/25/2015] [Accepted: 07/02/2015] [Indexed: 10/23/2022]
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Norepinephrine and dopamine transmission in 2 limbic regions differentially respond to acute noxious stimulation. Pain 2015; 156:318-327. [PMID: 25599453 DOI: 10.1097/01.j.pain.0000460312.79195.ed] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Central dopamine and norepinephrine regulate behavioral and physiological responses during rewarding and aversive stimuli. Here, we investigated and compared norepinephrine and dopamine transmission in 2 limbic structures, the ventral bed nucleus of the stria terminalis and the nucleus accumbens shell of anesthetized rats, respectively, in response to acute tail pinch, a noxious stimulus. Norepinephrine release in the ventral bed nucleus of the stria terminalis responded monophasically, increasing at the time of the tail pinch and remaining elevated for a period after its cessation. In contrast, dopamine transmission in the nucleus accumbens shell displayed a heterogeneous and time-locked response to tail pinch. For most trials, there was a suppression of extracellular dopamine concentration throughout the duration of the stimuli. At the termination of the stimuli, however, extracellular dopamine either recovered back to or spiked above the initial baseline concentration. These signaling patterns were more clearly observed after administration of selective catecholamine autoreceptor and transporter inhibitors. The results suggest that the opposing responses of these catecholamines can provide integration of noxious inputs to influence behavioral outputs appropriate for survival such as escape or fighting.
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Chronic Back Pain Is Associated with Alterations in Dopamine Neurotransmission in the Ventral Striatum. J Neurosci 2015; 35:9957-65. [PMID: 26156996 DOI: 10.1523/jneurosci.4605-14.2015] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Back pain is common in the general population, but only a subgroup of back pain patients develops a disabling chronic pain state. The reasons for this are incompletely understood, but recent evidence implies that both preexisting and pain-related variations in the structure and function of the nervous system may contribute significantly to the development of chronic pain. Here, we addressed the role of striatal dopamine (DA) D2/D3 receptor (D2/D3R) function in chronic non-neuropathic back pain (CNBP) by comparing CNBP patients and healthy controls using PET and the D2/D3R-selective radioligand [(11)C]raclopride. D2/D3R availability was measured at baseline and during a pain challenge, yielding in vivo measures of receptor availability (binding potential, BPND) and DA release (change in BPND from baseline to activated state). At baseline, CNBP patients demonstrated reductions in D2/D3R BPND in the ventral striatum compared with controls. These reductions were associated with greater positive affect scores and pain tolerance measures. The reductions in D2/D3R BPND were also correlated with μ-opioid receptor BPND and pain-induced endogenous opioid system activation in the amygdala, further associated with measures of positive affect, the affective component of back pain and pain tolerance. During the pain challenge, lower magnitudes of DA release, and therefore D2/D3R activation, were also found in the ventral striatum in the CNBP sample compared with controls. Our results show that CNBP is associated with adaptations in ventral striatal D2/D3R function, which, together with endogenous opioid system function, contribute to the sensory and affective-motivational features of CNBP. SIGNIFICANCE STATEMENT The neural systems that underlie chronic pain remain poorly understood. Here, using PET, we provide insight into the molecular mechanisms that regulate sensory and affective dimensions of pain in chronic back pain patients. We found that patients with back pain have alterations in brain dopamine function that are associated with measures of pain sensitivity and affective state, but also with brain endogenous opioid system functional measures. These findings suggest that brain dopamine-opioid interactions are involved in the pathophysiology of chronic pain, which has potential therapeutic implications. Our results may also help to explain individual variation in susceptibility to opioid medication misuse and eventual addiction in the context of chronic pain.
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80
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The neuroscience of placebo effects: connecting context, learning and health. Nat Rev Neurosci 2015; 16:403-18. [PMID: 26087681 DOI: 10.1038/nrn3976] [Citation(s) in RCA: 438] [Impact Index Per Article: 48.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Placebo effects are beneficial effects that are attributable to the brain-mind responses to the context in which a treatment is delivered rather than to the specific actions of the drug. They are mediated by diverse processes--including learning, expectations and social cognition--and can influence various clinical and physiological outcomes related to health. Emerging neuroscience evidence implicates multiple brain systems and neurochemical mediators, including opioids and dopamine. We present an empirical review of the brain systems that are involved in placebo effects, focusing on placebo analgesia, and a conceptual framework linking these findings to the mind-brain processes that mediate them. This framework suggests that the neuropsychological processes that mediate placebo effects may be crucial for a wide array of therapeutic approaches, including many drugs.
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Dias EV, Sartori CR, Marião PR, Vieira AS, Camargo LC, Athie MCP, Pagliusi MO, Tambeli CH, Parada CA. Nucleus accumbens dopaminergic neurotransmission switches its modulatory action in chronification of inflammatory hyperalgesia. Eur J Neurosci 2015; 42:2380-9. [DOI: 10.1111/ejn.13015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 07/03/2015] [Accepted: 07/06/2015] [Indexed: 12/30/2022]
Affiliation(s)
- Elayne Vieira Dias
- Department of Structural and Functional Biology; State University of Campinas; Rua Monteiro Lobato 255, Cidade Universitaria Zeferino Vaz Box 6109 13083-865 Campinas SP Brazil
| | - César Renato Sartori
- Department of Structural and Functional Biology; State University of Campinas; Rua Monteiro Lobato 255, Cidade Universitaria Zeferino Vaz Box 6109 13083-865 Campinas SP Brazil
| | - Paula Ramos Marião
- Department of Structural and Functional Biology; State University of Campinas; Rua Monteiro Lobato 255, Cidade Universitaria Zeferino Vaz Box 6109 13083-865 Campinas SP Brazil
| | - André Schwambach Vieira
- Department of Structural and Functional Biology; State University of Campinas; Rua Monteiro Lobato 255, Cidade Universitaria Zeferino Vaz Box 6109 13083-865 Campinas SP Brazil
| | - Lilian Calili Camargo
- Department of Structural and Functional Biology; State University of Campinas; Rua Monteiro Lobato 255, Cidade Universitaria Zeferino Vaz Box 6109 13083-865 Campinas SP Brazil
| | - Maria Carolina Pedro Athie
- Department of Structural and Functional Biology; State University of Campinas; Rua Monteiro Lobato 255, Cidade Universitaria Zeferino Vaz Box 6109 13083-865 Campinas SP Brazil
| | - Marco Oreste Pagliusi
- Department of Structural and Functional Biology; State University of Campinas; Rua Monteiro Lobato 255, Cidade Universitaria Zeferino Vaz Box 6109 13083-865 Campinas SP Brazil
| | - Claudia Herrera Tambeli
- Department of Structural and Functional Biology; State University of Campinas; Rua Monteiro Lobato 255, Cidade Universitaria Zeferino Vaz Box 6109 13083-865 Campinas SP Brazil
| | - Carlos Amilcar Parada
- Department of Structural and Functional Biology; State University of Campinas; Rua Monteiro Lobato 255, Cidade Universitaria Zeferino Vaz Box 6109 13083-865 Campinas SP Brazil
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Cury R, Galhardoni R, Fonoff E, Perez Lloret S, dos Santos Ghilardi M, Barbosa E, Teixeira M, Ciampi de Andrade D. Sensory abnormalities and pain in Parkinson disease and its modulation by treatment of motor symptoms. Eur J Pain 2015; 20:151-65. [DOI: 10.1002/ejp.745] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/16/2015] [Indexed: 01/07/2023]
Affiliation(s)
- R.G. Cury
- Pain Center; Department of Neurology; University of São Paulo; São Paulo Brazil
- Pain Center; Instituto do Câncer do Estado de São Paulo; São Paulo Brazil
- Movement Disorders Group; Department of Neurology; University of São Paulo; São Paulo Brazil
| | - R. Galhardoni
- Pain Center; Department of Neurology; University of São Paulo; São Paulo Brazil
| | - E.T. Fonoff
- Pain Center; Department of Neurology; University of São Paulo; São Paulo Brazil
- Transcranial Magnetic Stimulation Laboratory; Psychiatry Institute; University of São Paulo; São Paulo Brazil
- Neurosurgery Division; Department of Neurology; University of São Paulo; São Paulo Brazil
| | - S. Perez Lloret
- Laboratory of Clinical Pharmacology and Epidemiology; Catholic University; Buenos Aires Argentina
| | | | - E.R. Barbosa
- Movement Disorders Group; Department of Neurology; University of São Paulo; São Paulo Brazil
| | - M.J. Teixeira
- Pain Center; Department of Neurology; University of São Paulo; São Paulo Brazil
- Pain Center; Instituto do Câncer do Estado de São Paulo; São Paulo Brazil
- Movement Disorders Group; Department of Neurology; University of São Paulo; São Paulo Brazil
- Transcranial Magnetic Stimulation Laboratory; Psychiatry Institute; University of São Paulo; São Paulo Brazil
- Neurosurgery Division; Department of Neurology; University of São Paulo; São Paulo Brazil
| | - D. Ciampi de Andrade
- Pain Center; Department of Neurology; University of São Paulo; São Paulo Brazil
- Pain Center; Instituto do Câncer do Estado de São Paulo; São Paulo Brazil
- Transcranial Magnetic Stimulation Laboratory; Psychiatry Institute; University of São Paulo; São Paulo Brazil
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83
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Blockade of D1-like dopamine receptors within the ventral tegmental area and nucleus accumbens attenuates antinociceptive responses induced by chemical stimulation of the lateral hypothalamus. Neurosci Lett 2015; 599:61-6. [DOI: 10.1016/j.neulet.2015.05.047] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 05/15/2015] [Accepted: 05/21/2015] [Indexed: 11/18/2022]
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84
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Effects of the Fourth Ventricle Compression in the Regulation of the Autonomic Nervous System: A Randomized Control Trial. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2015. [PMID: 26199632 PMCID: PMC4496659 DOI: 10.1155/2015/148285] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Introduction. Dysfunction of the autonomic nervous system is an important factor in the development of chronic pain. Fourth ventricle compression (CV-4) has been shown to influence autonomic activity. Nevertheless, the physiological mechanisms behind these effects remain unclear. Objectives. This study is aimed at evaluating the effects of fourth ventricle compression on the autonomic nervous system. Methods. Forty healthy adults were randomly assigned to an intervention group, on whom CV-4 was performed, or to a control group, who received a placebo intervention (nontherapeutic touch on the occipital bone). In both groups, plasmatic catecholamine levels, blood pressure, and heart rate were measured before and immediately after the intervention. Results. No effects related to the intervention were found. Although a reduction of norepinephrine, systolic blood pressure, and heart rate was found after the intervention, it was not exclusive to the intervention group. In fact, only the control group showed an increment of dopamine levels after intervention. Conclusion. Fourth ventricle compression seems not to have any effect in plasmatic catecholamine levels, blood pressure, or heart rate. Further studies are needed to clarify the CV-4 physiologic mechanisms and clinical efficacy in autonomic regulation and pain treatment.
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85
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Chemical stimulation of the lateral hypothalamus by carbachol attenuated the formalin-induced pain behaviors in rats. Pharmacol Biochem Behav 2015; 129:105-10. [DOI: 10.1016/j.pbb.2014.12.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 12/18/2014] [Accepted: 12/27/2014] [Indexed: 11/18/2022]
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86
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Woo CW, Roy M, Buhle JT, Wager TD. Distinct brain systems mediate the effects of nociceptive input and self-regulation on pain. PLoS Biol 2015; 13:e1002036. [PMID: 25562688 PMCID: PMC4285399 DOI: 10.1371/journal.pbio.1002036] [Citation(s) in RCA: 185] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 11/21/2014] [Indexed: 12/19/2022] Open
Abstract
Two distinct parallel neural systems independently contribute to our overall experience of pain – separately modulated by noxious input and by cognitive self-regulation. Cognitive self-regulation can strongly modulate pain and emotion. However, it is unclear whether self-regulation primarily influences primary nociceptive and affective processes or evaluative ones. In this study, participants engaged in self-regulation to increase or decrease pain while experiencing multiple levels of painful heat during functional magnetic resonance imaging (fMRI) imaging. Both heat intensity and self-regulation strongly influenced reported pain, but they did so via two distinct brain pathways. The effects of stimulus intensity were mediated by the neurologic pain signature (NPS), an a priori distributed brain network shown to predict physical pain with over 90% sensitivity and specificity across four studies. Self-regulation did not influence NPS responses; instead, its effects were mediated through functional connections between the nucleus accumbens and ventromedial prefrontal cortex. This pathway was unresponsive to noxious input, and has been broadly implicated in valuation, emotional appraisal, and functional outcomes in pain and other types of affective processes. These findings provide evidence that pain reports are associated with two dissociable functional systems: nociceptive/affective aspects mediated by the NPS, and evaluative/functional aspects mediated by a fronto-striatal system. Does cognitive self-regulation influence pain experience by affecting the primary representations of painful (nociceptive) stimuli in the brain? Or does it regulate reported pain via a neural pathway that is distinct from the one that mediates nociceptive pain? The present study demonstrates that nociceptive and cognitive manipulations of pain influence two distinct, separable neural systems, which operate together to construct the pain experience. The neurologic pain signature (NPS) mediates the effects of noxious input, whereas a fronto-striatal pathway connecting nucleus accumbens and ventromedial prefrontal cortex mediates the effects of cognitive self-regulation of pain. These findings help move the field beyond the “one system” view of pain as a primarily nociceptive process, and provide a foundation for new approaches to multidimensional pain assessment and treatment.
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Affiliation(s)
- Choong-Wan Woo
- Department of Psychology and Neuroscience, University of Colorado, Boulder, Colorado, United States of America
- Institute of Cognitive Science, University of Colorado, Boulder, Colorado, United States of America
| | - Mathieu Roy
- Department of Psychology and Neuroscience, University of Colorado, Boulder, Colorado, United States of America
- Institute of Cognitive Science, University of Colorado, Boulder, Colorado, United States of America
| | - Jason T. Buhle
- Department of Psychology, Columbia University, New York, New York, United States of America
| | - Tor D. Wager
- Department of Psychology and Neuroscience, University of Colorado, Boulder, Colorado, United States of America
- Institute of Cognitive Science, University of Colorado, Boulder, Colorado, United States of America
- * E-mail:
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87
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Navratilova E, Porreca F. Reward and motivation in pain and pain relief. Nat Neurosci 2014; 17:1304-12. [PMID: 25254980 PMCID: PMC4301417 DOI: 10.1038/nn.3811] [Citation(s) in RCA: 313] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2014] [Accepted: 08/18/2014] [Indexed: 12/13/2022]
Abstract
Pain is fundamentally unpleasant, a feature that protects the organism by promoting motivation and learning. Relief of aversive states, including pain, is rewarding. The aversiveness of pain, as well as the reward from relief of pain, is encoded by brain reward/motivational mesocorticolimbic circuitry. In this Review, we describe current knowledge of the impact of acute and chronic pain on reward/motivation circuits gained from preclinical models and from human neuroimaging. We highlight emerging clinical evidence suggesting that anatomical and functional changes in these circuits contribute to the transition from acute to chronic pain. We propose that assessing activity in these conserved circuits can offer new outcome measures for preclinical evaluation of analgesic efficacy to improve translation and speed drug discovery. We further suggest that targeting reward/motivation circuits may provide a path for normalizing the consequences of chronic pain to the brain, surpassing symptomatic management to promote recovery from chronic pain.
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Affiliation(s)
- Edita Navratilova
- Department of Pharmacology, University of Arizona Health Science Center, Tucson, Arizona, USA
| | - Frank Porreca
- Department of Pharmacology, University of Arizona Health Science Center, Tucson, Arizona, USA
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88
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Jääskeläinen SK, Lindholm P, Valmunen T, Pesonen U, Taiminen T, Virtanen A, Lamusuo S, Forssell H, Hagelberg N, Hietala J, Pertovaara A. Variation in the dopamine D2 receptor gene plays a key role in human pain and its modulation by transcranial magnetic stimulation. Pain 2014; 155:2180-7. [DOI: 10.1016/j.pain.2014.08.029] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 08/22/2014] [Accepted: 08/22/2014] [Indexed: 10/24/2022]
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89
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Abstract
The search for analgesics with fewer side effects and less abuse potential has had limited success. A recent study identifies an analgesic alkaloid compound from Corydalis yanhusuo, a traditional Chinese medicinal herb that has a surprising mechanism of action.
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Affiliation(s)
- Susan L Ingram
- Department of Neurological Surgery, Oregon Health & Science University, Portland, OR 97239, USA.
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90
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Cobacho N, de la Calle JL, Paíno CL. Dopaminergic modulation of neuropathic pain: analgesia in rats by a D2-type receptor agonist. Brain Res Bull 2014; 106:62-71. [PMID: 24959942 DOI: 10.1016/j.brainresbull.2014.06.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 06/13/2014] [Accepted: 06/16/2014] [Indexed: 11/28/2022]
Abstract
Experimental studies have shown that dopaminergic mechanisms can modulate both nociception and chronic pain perception, but such property is not exploited pharmacologically at the clinical level. We have previously shown that levodopa produces D2-receptor-mediated antiallodynic effects in rats with peripheral mononeuropathy. Here, we test the effects of a D2-type receptor (D2R) agonist, quinpirole, on neuropathic pain in rats. Allodynic responses to cooling and light touch were measured in the hind limbs of rats with chronic constriction injury of one sciatic nerve. Single intraperitoneal injection of quinpirole (1 mg/kg) totally inhibited cold and tactile allodynic responses for over 3 and 48 h, respectively. At that dose, quinpirole had no effect on nocifensive responses to heat. Lumbar intrathecal injection of quinpirole produced short-term inhibition of the responses to cold and tactile stimuli, suggesting that spinal mechanisms may contribute to the antiallodynic activity of quinpirole. Chronic subcutaneous infusion of quinpirole by implanted Alzet pumps (0.025 mg/kg·day) provided a slowly progressing inhibition of cold and tactile allodynic responses, which re-emerged after the pumps were removed. These experiments show the involvement of dopaminergic systems in the modulation of chronic allodynias and provide experimental support for proposing the use of D2R agonists for neuropathic pain relief.
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Affiliation(s)
- Nuria Cobacho
- Service of Neurobiology-Research, IRYCIS, Hospital Ramón y Cajal, Carretera de Colmenar km 9, 28034 Madrid, Spain
| | | | - Carlos Luis Paíno
- Service of Neurobiology-Research, IRYCIS, Hospital Ramón y Cajal, Carretera de Colmenar km 9, 28034 Madrid, Spain.
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91
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Dieb W, Ouachikh O, Durif F, Hafidi A. Lesion of the dopaminergic nigrostriatal pathway induces trigeminal dynamic mechanical allodynia. Brain Behav 2014; 4:368-80. [PMID: 24944866 PMCID: PMC4055187 DOI: 10.1002/brb3.214] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Revised: 12/18/2013] [Accepted: 12/20/2013] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Pain constitutes the major non motor syndrome in Parkinson's disease (PD) and includes neuropathic pain; however current drug therapies used to alleviate it have only limited efficacy. This is probably due to poor understanding of the mechanisms underlying it. AIMS We investigated a major class of trigeminal neuropathic pain, dynamic mechanical allodynia (DMA), in a rat model of PD and in which a bilateral 6-hydroxy dopamine (6-OHDA) injection was administered to produce a lesion of the nigrostriatal dopaminergic pathway. RESULTS AND DISCUSSION Lesioned animals presented significant DMA in the orofacial area that occurred from 4 days to 5 weeks post-injury. To investigate a segmental implication in the neuropathic pain induced by dopamine depletion, the expression of the isoform gamma of the protein kinase C (PKCg) and phosphorylated extracellular signal-regulated kinases 1/2 (pERK1/2) was explored in the medullary dorsal horn (MDH). There was a high increase in PKCg expression in the III and IIi laminae of the MDH of lesioned-animals compared to shams. pERK1/2 expression was also significantly high in the ipsilateral MDH of lesioned rats in response to non-noxious tactile stimulus of the orofacial region. Since pERK1/2 is expressed only in response to nociceptive stimuli in the dorsal spinal horn, the current study demonstrates that non-noxious stimuli evoke allodynic response. Intraperitoneal and intracisternal administrations of bromocriptine, a dopamine 2 receptor (D2R) agonist, significantly decreased DMA compared to control rats injected with saline. These data demonstrate for the first time that nigrostriatal dopaminergic depletion produces trigeminal neuropathic pain that at least involves a segmental mechanism. In addition, bromocriptine was shown to have a remarkable analgesic effect on this neuropathic pain symptom.
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Affiliation(s)
- Wisam Dieb
- Laboratoire de neuro-psychopharmacology des systèmes dopaminergiques sous corticaux, Clermont Université, Université d'AuvergneClermont-Ferrand, EA7280, France
| | - Omar Ouachikh
- Laboratoire de neuro-psychopharmacology des systèmes dopaminergiques sous corticaux, Clermont Université, Université d'AuvergneClermont-Ferrand, EA7280, France
| | - Franck Durif
- Laboratoire de neuro-psychopharmacology des systèmes dopaminergiques sous corticaux, Clermont Université, Université d'AuvergneClermont-Ferrand, EA7280, France
- Service de Neurologie, CHU Clermont-FerrandClermont-Ferrand, 63000, France
| | - Aziz Hafidi
- Laboratoire de neuro-psychopharmacology des systèmes dopaminergiques sous corticaux, Clermont Université, Université d'AuvergneClermont-Ferrand, EA7280, France
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92
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Eastwood EC, Phillips TJ. Opioid sensitivity in mice selectively bred to consume or not consume methamphetamine. Addict Biol 2014; 19:370-9. [PMID: 23145527 DOI: 10.1111/adb.12003] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
There has been little investigation of genetic factors and associated mechanisms that influence risk for development of methamphetamine (MA) dependence. Selectively bred mouse lines that exhibit high (MAHDR) or low (MALDR) levels of MA intake in a two-bottle choice MA drinking (MADR) procedure provide a genetic tool for this purpose. These lines were used to determine whether opioid sensitivity and MA intake are genetically associated, because opioid-mediated pathways influence some effects of MA. Sensitivity to the analgesic effects of the μ-opioid receptor (MOP-r) agonist fentanyl (0.05, 0.1, 0.2, 0.4 mg/kg) was examined using two acute thermal tests (hot plate and tail flick) and one chronic pain test (magnesium sulfate abdominal constriction). Locomotor stimulant responses to fentanyl (0.05, 0.1, 0.2, 0.4 mg/kg) and morphine (10, 20, 30 mg/kg) were also examined. In addition, MADR was measured in the progenitor strains [(C57BL/6J (B6), DBA/2J (D2)] of the F2 population from which the selected lines were generated. The MADR lines did not differ in sensitivity to the analgesic effects of fentanyl; however, MALDR mice exhibited greater locomotor activation than MAHDR mice to both fentanyl and morphine. D2 mice consumed more MA than B6 mice. The line differences for MA consumption and morphine activation recapitulated B6 and D2 strain differences for these two traits, but not strain differences previously found for opioid analgesic responses. These results support a negative genetic correlation between MA consumption and sensitivity to the stimulant effects of opioids and suggest the involvement of MOP-r regulated systems in MA intake.
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Affiliation(s)
- Emily C. Eastwood
- Department of Behavioral Neuroscience and Methamphetamine Abuse Research Center; Oregon Health & Science University; Portland OR USA
| | - Tamara J. Phillips
- Department of Behavioral Neuroscience and Methamphetamine Abuse Research Center; Oregon Health & Science University; Portland OR USA
- Veterans Affairs Medical Center; Portland OR USA
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93
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Tiemann L, Heitmann H, Schulz E, Baumkötter J, Ploner M. Dopamine precursor depletion influences pain affect rather than pain sensation. PLoS One 2014; 9:e96167. [PMID: 24760082 PMCID: PMC3997524 DOI: 10.1371/journal.pone.0096167] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 04/03/2014] [Indexed: 01/15/2023] Open
Abstract
Pain is a multidimensional experience, which includes sensory, cognitive, and affective aspects. Converging lines of evidence indicate that dopaminergic neurotransmission plays an important role in human pain perception. However, the precise effects of dopamine on different aspects of pain perception remain to be elucidated. To address this question, we experimentally decreased dopaminergic neurotransmission in 22 healthy human subjects using Acute Phenylalanine and Tyrosine Depletion (APTD). During APTD and a control condition we applied brief painful laser stimuli to the hand, assessed different aspects of pain perception, and recorded electroencephalographic responses. APTD-induced decreases of cerebral dopaminergic activity did not influence sensory aspects of pain perception. In contrast, APTD yielded increases of pain unpleasantness. The increases of unpleasantness ratings positively correlated with effectiveness of APTD. Our finding of an influence of dopaminergic neurotransmission on affective but not sensory aspects of phasic pain suggests that analgesic effects of dopamine might be mediated by indirect effects on pain affect rather than by direct effects on ascending nociceptive signals. These findings contribute to our understanding of the complex relationship between dopamine and pain perception, which may play a role in various clinical pain states.
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Affiliation(s)
- Laura Tiemann
- Department of Neurology, Technische Universität München, Munich, Germany
- TUM-Neuroimaging Center, Technische Universität München, Munich, Germany
- * E-mail:
| | - Henrik Heitmann
- Department of Neurology, Technische Universität München, Munich, Germany
- TUM-Neuroimaging Center, Technische Universität München, Munich, Germany
| | - Enrico Schulz
- Department of Neurology, Technische Universität München, Munich, Germany
- TUM-Neuroimaging Center, Technische Universität München, Munich, Germany
| | - Jochen Baumkötter
- Department of Pediatrics, Technische Universität München, Munich, Germany
| | - Markus Ploner
- Department of Neurology, Technische Universität München, Munich, Germany
- TUM-Neuroimaging Center, Technische Universität München, Munich, Germany
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94
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Cardoso-Cruz H, Dourado M, Monteiro C, Matos MR, Galhardo V. Activation of dopaminergic D2/D3 receptors modulates dorsoventral connectivity in the hippocampus and reverses the impairment of working memory after nerve injury. J Neurosci 2014; 34:5861-73. [PMID: 24760846 PMCID: PMC6608290 DOI: 10.1523/jneurosci.0021-14.2014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Revised: 02/25/2014] [Accepted: 02/28/2014] [Indexed: 11/21/2022] Open
Abstract
Dopamine plays an important role in several forms of synaptic plasticity in the hippocampus, a crucial brain structure for working memory (WM) functioning. In this study, we evaluated whether the working-memory impairment characteristic of animal models of chronic pain is dependent on hippocampal dopaminergic signaling. To address this issue, we implanted multichannel arrays of electrodes in the dorsal and ventral hippocampal CA1 region of rats and recorded the neuronal activity during a food-reinforced spatial WM task of trajectory alternation. Within-subject behavioral performance and patterns of dorsoventral neuronal activity were assessed before and after the onset of persistent neuropathic pain using the Spared Nerve Injury (SNI) model of neuropathic pain. Our results show that the peripheral nerve lesion caused a disruption in WM and in hippocampus spike activity and that this disruption was reversed by the systemic administration of the dopamine D2/D3 receptor agonist quinpirole (0.05 mg/kg). In SNI animals, the administration of quinpirole restored both the performance-related and the task-related spike activity to the normal range characteristic of naive animals, whereas quinpirole in sham animals caused the opposite effect. Quinpirole also reversed the abnormally low levels of hippocampus dorsoventral connectivity and phase coherence. Together with our finding of changes in gene expression of dopamine receptors and modulators after the onset of the nerve injury model, these results suggest that disruption of the dopaminergic balance in the hippocampus may be crucial for the clinical neurological and cognitive deficits observed in patients with painful syndromes.
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Affiliation(s)
- Helder Cardoso-Cruz
- Departamento de Biologia Experimental, Faculdade de Medicina, Universidade do Porto, 4200-319 Porto, Portugal
- Instituto de Biologia Molecular e Celular, Grupo de Morfofisiologia do Sistema Somatosensitivo, Universidade do Porto, 4150-180 Porto, Portugal, and
| | - Margarida Dourado
- Departamento de Biologia Experimental, Faculdade de Medicina, Universidade do Porto, 4200-319 Porto, Portugal
- Instituto de Biologia Molecular e Celular, Grupo de Morfofisiologia do Sistema Somatosensitivo, Universidade do Porto, 4150-180 Porto, Portugal, and
- Programa Doutoral em Neurociências, Faculdade de Medicina, Universidade do Porto. 4200-319 Porto, Portugal
| | - Clara Monteiro
- Departamento de Biologia Experimental, Faculdade de Medicina, Universidade do Porto, 4200-319 Porto, Portugal
- Instituto de Biologia Molecular e Celular, Grupo de Morfofisiologia do Sistema Somatosensitivo, Universidade do Porto, 4150-180 Porto, Portugal, and
| | - Mariana R. Matos
- Departamento de Biologia Experimental, Faculdade de Medicina, Universidade do Porto, 4200-319 Porto, Portugal
- Instituto de Biologia Molecular e Celular, Grupo de Morfofisiologia do Sistema Somatosensitivo, Universidade do Porto, 4150-180 Porto, Portugal, and
| | - Vasco Galhardo
- Departamento de Biologia Experimental, Faculdade de Medicina, Universidade do Porto, 4200-319 Porto, Portugal
- Instituto de Biologia Molecular e Celular, Grupo de Morfofisiologia do Sistema Somatosensitivo, Universidade do Porto, 4150-180 Porto, Portugal, and
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95
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Stehlik R, Ulfberg J, Hedner J, Grote L. High prevalence of restless legs syndrome among women with multi-site pain: a population-based study in Dalarna, Sweden. Eur J Pain 2014; 18:1402-9. [PMID: 24700622 DOI: 10.1002/ejp.504] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/03/2014] [Indexed: 11/08/2022]
Abstract
BACKGROUND The chronic pain (CP) and chronic multi-site pain (CMP) condition is a highly prevalent health problem. Several studies have reported a high (31-64%) prevalence of co-morbid restless legs syndrome (RLS) in patients with fibromyalgia, one specifically defined form of chronic widespread pain. The current study explored the association between CMP and RLS. METHOD The study included 4040 respondents to a postal questionnaire sent to 10,000 women in the age range of 18-64 years and randomly selected from the general population. Complete questionnaire data on type (acute/chronic), degree (mild to severe) and spreading (0-5 body zones) of pain, as well as RLS symptoms (validated questionnaire), were obtained from 3060 subjects. Information on lifestyle, anthropometrics, co-morbidities and medication was collected. RESULTS RLS prevalence increased from 9.6% in subjects with no report of pain to 23,9%, 26.4%, 39.2%, 44.9% and 54.8% in those reporting one, two, three, four and five pain areas, respectively (p < 0.001). Further, RLS prevalence increased from 9.6% (no pain) to 27.9%, 37.9% and 42.4% in subjects with mild, moderate and severe chronic pain (p < 0.001). Multi-site pain, pain localized in the leg, extended pain duration and co-morbid psychiatric disorder were all independently associated with a RLS diagnosis in a multiple regression analysis. CONCLUSION The prevalence of RLS increased progressively with pain severity and even more sharply with the degree of pain spreading in women recruited from the general population. Both acute and chronic pain was associated with RLS-related symptoms.
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Affiliation(s)
- R Stehlik
- Pain Center, Skonvik Medical Rehabilitation Clinic, Säter, Sweden; Center for Sleep and Vigilance Disorders, Sahlgrenska Academy, Gothenburg University, Sweden
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96
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Nekovarova T, Yamamotova A, Vales K, Stuchlik A, Fricova J, Rokyta R. Common mechanisms of pain and depression: are antidepressants also analgesics? Front Behav Neurosci 2014; 8:99. [PMID: 24723864 PMCID: PMC3971163 DOI: 10.3389/fnbeh.2014.00099] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2013] [Accepted: 03/09/2014] [Indexed: 12/16/2022] Open
Abstract
Neither pain, nor depression exist as independent phenomena per se, they are highly subjective inner states, formed by our brain and built on the bases of our experiences, cognition and emotions. Chronic pain is associated with changes in brain physiology and anatomy. It has been suggested that the neuronal activity underlying subjective perception of chronic pain may be divergent from the activity associated with acute pain. We will discuss the possible common pathophysiological mechanism of chronic pain and depression with respect to the default mode network of the brain, neuroplasticity and the effect of antidepressants on these two pathological conditions. The default mode network of the brain has an important role in the representation of introspective mental activities and therefore can be considered as a nodal point, common for both chronic pain and depression. Neuroplasticity which involves molecular, cellular and synaptic processes modifying connectivity between neurons and neuronal circuits can also be affected by pathological states such as chronic pain or depression. We suppose that pathogenesis of depression and chronic pain shares common negative neuroplastic changes in the central nervous system (CNS). The positive impact of antidepressants would result in a reduction of these pathological cellular/molecular processes and in the amelioration of symptoms, but it may also increase survival times and quality of life of patients with chronic cancer pain.
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Affiliation(s)
- Tereza Nekovarova
- Institute of Physiology, Academy of Sciences of the Czech RepublicPrague, Czech Republic
- Department of Zoology, Ecology and Ethology Research Group, Faculty of Natural Science, Charles University in PraguePrague, Czech Republic
| | - Anna Yamamotova
- Department of Normal, Pathological and Clinical Physiology, Third Faculty of Medicine, Charles University in PraguePrague, Czech Republic
| | - Karel Vales
- Institute of Physiology, Academy of Sciences of the Czech RepublicPrague, Czech Republic
| | - Ales Stuchlik
- Institute of Physiology, Academy of Sciences of the Czech RepublicPrague, Czech Republic
| | - Jitka Fricova
- Department of Anesthesiology and Intensive Care Medicine, Pain Management Center, First Faculty of Medicine and General University Hospital, Charles University in PraguePrague, Czech Republic
| | - Richard Rokyta
- Department of Normal, Pathological and Clinical Physiology, Third Faculty of Medicine, Charles University in PraguePrague, Czech Republic
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97
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Burattini C, Battistini G, Tamagnini F, Aicardi G. Low-frequency stimulation evokes serotonin release in the nucleus accumbens and induces long-term depression via production of endocannabinoid. J Neurophysiol 2014; 111:1046-55. [DOI: 10.1152/jn.00498.2013] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The nucleus accumbens (NAc), a major component of the mesolimbic system, is involved in the mediation of reinforcing and addictive properties of many dependence-producing drugs. Glutamatergic synapses within the NAc can express plasticity, including a form of endocannabinoid (eCB)-long-term depression (LTD). Recent evidences demonstrate cross talk between eCB signaling pathways and those of other receptor systems, including serotonin (5-HT); the extensive colocalization of CB1 and 5-HT receptors within the NAc suggests the potential for interplay between them. In the present study, we found that 20-min low-frequency (4 Hz) stimulation (LFS-4Hz) of glutamatergic afferences in rat brain slices induces a novel form of eCB-LTD in the NAc core, which requires 5-HT2 and CB1 receptor activation and L-type voltage-gated Ca2+ channel opening. Moreover, we found that exogenous 5-HT application (5 μM, 20 min) induces an analogous LTD (5-HT-LTD) at the same synapses, requiring the activation of the same receptors and the opening of the same Ca2+ channels; LFS-4Hz-LTD and 5-HT-LTD were mutually occlusive. Present results suggest that LFS-4Hz induces the release of 5-HT, which acts at 5-HT2 postsynaptic receptors, increasing Ca2+ influx through L-type voltage-gated channels and 2-arachidonoylglycerol production and release; the eCB travels retrogradely and binds to presynaptic CB1 receptors, causing a long-lasting decrease of glutamate release, resulting in LTD. These observations might be helpful to understand the neurophysiological mechanisms underlying drug addiction, major depression, and other psychiatric disorders characterized by dysfunction of 5-HT neurotransmission in the NAc.
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Affiliation(s)
- Costanza Burattini
- Department for Life Quality Studies, University of Bologna, Bologna, Italy; and
| | - Giulia Battistini
- Department for Life Quality Studies, University of Bologna, Bologna, Italy; and
| | - Francesco Tamagnini
- Department for Life Quality Studies, University of Bologna, Bologna, Italy; and
| | - Giorgio Aicardi
- Department for Life Quality Studies, University of Bologna, Bologna, Italy; and
- Interdepartmental Center “Luigi Galvani” for the Study of Biophysics, Bioinformatics and Biocomplexity, University of Bologna, Bologna, Italy
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Marcondes Sari MH, Guerra Souza AC, Gonçalves Rosa S, Souza D, Dorneles Rodrigues OE, Wayne Nogueira C. Contribution of dopaminergic and adenosinergic systems in the antinociceptive effect of p-chloro-selenosteroid. Eur J Pharmacol 2014; 725:79-86. [DOI: 10.1016/j.ejphar.2014.01.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 12/20/2013] [Accepted: 01/07/2014] [Indexed: 12/28/2022]
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100
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Wade CL, Krumenacher P, Kitto KF, Peterson CD, Wilcox GL, Fairbanks CA. Effect of chronic pain on fentanyl self-administration in mice. PLoS One 2013; 8:e79239. [PMID: 24260176 PMCID: PMC3829846 DOI: 10.1371/journal.pone.0079239] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 09/19/2013] [Indexed: 11/18/2022] Open
Abstract
The development of opioid addiction in subjects with established chronic pain is an area that is poorly understood. It is critically important to clearly understand the neurobiology associated with propensity toward conversion to addiction under conditions of chronic pain. To pose the question whether the presence of chronic pain influences motivation to self-administer opioids for reward, we applied a combination of rodent models of chronic mechanical hyperalgesia and opioid self-administration. We studied fentanyl self-administration in mice under three conditions that induce chronic mechanical hyperalgesia: inflammation, peripheral nerve injury, and repeated chemotherapeutic injections. Responding for fentanyl was compared among these conditions and their respective standard controls (naïve condition, vehicle injection or sham surgery). Acquisition of fentanyl self-administration behavior was reduced or absent in all three conditions of chronic hyperalgesia relative to control mice with normal sensory thresholds. To control for potential impairment in ability to learn the lever-pressing behavior or perform the associated motor tasks, all three groups were evaluated for acquisition of food-maintained responding. In contrast to the opioid, chronic hyperalgesia did not interfere with the reinforcing effect of food. These studies indicate that the establishment of chronic hyperalgesia is associated with reduced or ablated motivation to seek opioid reward in mice.
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Affiliation(s)
- Carrie L. Wade
- Department of Pharmacology, University of Minnesota, Minneapolis, Minnesota, United States of America
- Center for Pain Research, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Perry Krumenacher
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota, United States of America
- Center for Pain Research, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Kelley F. Kitto
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota, United States of America
- Center for Pain Research, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Cristina D. Peterson
- Department of Pharmaceutics, University of Minnesota, Minneapolis, Minnesota, United States of America
- Center for Pain Research, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - George L. Wilcox
- Department of Pharmacology, University of Minnesota, Minneapolis, Minnesota, United States of America
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota, United States of America
- Center for Pain Research, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Carolyn A. Fairbanks
- Department of Pharmacology, University of Minnesota, Minneapolis, Minnesota, United States of America
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota, United States of America
- Department of Pharmaceutics, University of Minnesota, Minneapolis, Minnesota, United States of America
- Center for Pain Research, University of Minnesota, Minneapolis, Minnesota, United States of America
- * E-mail:
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