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Saghafi M, Danesh E, Askari R, Mousavi Z, Haghparast A. Differential Roles of the D1- and D2-Like Dopamine Receptors Within the Ventral Tegmental Area in Modulating the Antinociception Induced by Forced Swim Stress in the Rat. Neurochem Res 2024; 49:143-156. [PMID: 37642894 DOI: 10.1007/s11064-023-04017-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 08/05/2023] [Accepted: 08/15/2023] [Indexed: 08/31/2023]
Abstract
Several preclinical and clinical studies indicate that exposure to acute stress may decrease pain perception and increases pain tolerance. This phenomenon is called stress-induced analgesia (SIA). A variety of neurotransmitters, including dopamine, is involved in the SIA. Dopaminergic neurons in the mesolimbic circuits, originating from the ventral tegmental area (VTA), play a crucial role in various motivational, rewarding, and pain events. The present study aimed to investigate the modulatory role of VTA dopaminergic receptors in the antinociceptive responses evoked by forced swim stress (FSS) in a model of acute pain. One hundred-five adult male albino Wistar rats were subjected to stereotaxic surgery for implanting a unilateral cannula into the VTA. After one week of recovery, separate groups of animals were given different doses of SCH23390 and Sulpiride (0.25, 1, and 4 µg/0.3 µl) as D1- and D2-like receptor antagonists into the VTA, respectively. Then, the animals were exposed to FSS for a 6-min period, and the pain threshold was measured using the tail-flick test over a 60-min time set intervals. Results indicated that exposure to FSS produces a prominent antinociceptive response, diminishing by blocking both dopamine receptors in the VTA. Nonetheless, the effect of a D1-like dopamine receptor antagonist on FSS-induced analgesia was more prominent than that of a D2-like dopamine receptor antagonist. The results demonstrated that VTA dopaminergic receptors contribute to the pain process in stressful situations, and it might be provided a practical approach to designing new therapeutic agents for pain management.
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Affiliation(s)
- Mohammad Saghafi
- Pharmacology and Toxicology Department, Faculty of Pharmacy and Pharmaceutical Sciences, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Elaheh Danesh
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, P.O.Box: 19615-1178, Tehran, Iran
| | - Reyhaneh Askari
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, P.O.Box: 19615-1178, Tehran, Iran
| | - Zahra Mousavi
- Pharmacology and Toxicology Department, Faculty of Pharmacy and Pharmaceutical Sciences, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Abbas Haghparast
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, P.O.Box: 19615-1178, Tehran, Iran.
- School of Cognitive Sciences, Institute for Research in Fundamental Sciences, Tehran, Iran.
- Department of Basic Sciences, Iranian Academy of Medical Sciences, Tehran, Iran.
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Barker DJ, Zhang S, Wang H, Estrin DJ, Miranda-Barrientos J, Liu B, Kulkarni RJ, de Deus JL, Morales M. Lateral preoptic area glutamate neurons relay nociceptive information to the ventral tegmental area. Cell Rep 2023; 42:113029. [PMID: 37632750 PMCID: PMC10584074 DOI: 10.1016/j.celrep.2023.113029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 04/28/2023] [Accepted: 08/09/2023] [Indexed: 08/28/2023] Open
Abstract
The ventral tegmental area (VTA) has been proposed to play a role in pain, but the brain structures modulating VTA activity in response to nociceptive stimuli remain unclear. Here, we demonstrate that the lateral preoptic area (LPO) glutamate neurons relay nociceptive information to the VTA. These LPO glutamatergic neurons synapsing on VTA neurons respond to nociceptive stimulation and conditioned stimuli predicting nociceptive stimulation and also mediate aversion. In contrast, LPO GABA neurons synapsing in the VTA mediate reward. By ultrastructural quantitative synaptic analysis, ex vivo electrophysiology, and functional neuroanatomy we identify a complex circuitry between LPO glutamatergic and GABAergic neurons and VTA dopaminergic, GABAergic, and glutamatergic neurons. We conclude that LPO glutamatergic neurons play a causal role in the processing of nociceptive stimuli and in relaying information about nociceptive stimuli. The pathway from LPO glutamatergic neurons to the VTA represents an unpredicted interface between peripheral nociceptive information and the limbic system.
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Affiliation(s)
- David J Barker
- Integrative Neuroscience Branch, Neuronal Networks Section, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD 21224, USA
| | - Shiliang Zhang
- Confocal and Electron Microscopy Core, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD 21224, USA
| | - Huiling Wang
- Integrative Neuroscience Branch, Neuronal Networks Section, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD 21224, USA
| | - David J Estrin
- Integrative Neuroscience Branch, Neuronal Networks Section, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD 21224, USA
| | - Jorge Miranda-Barrientos
- Integrative Neuroscience Branch, Neuronal Networks Section, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD 21224, USA
| | - Bing Liu
- Integrative Neuroscience Branch, Neuronal Networks Section, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD 21224, USA
| | - Rucha J Kulkarni
- Integrative Neuroscience Branch, Neuronal Networks Section, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD 21224, USA
| | - Junia Lara de Deus
- Integrative Neuroscience Branch, Neuronal Networks Section, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD 21224, USA
| | - Marisela Morales
- Integrative Neuroscience Branch, Neuronal Networks Section, National Institute on Drug Abuse Intramural Research Program, Baltimore, MD 21224, USA.
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Wang J, Li Z, Tu Y, Gao F. The Dopaminergic System in the Ventral Tegmental Area Contributes to Morphine Analgesia and Tolerance. Neuroscience 2023; 527:74-83. [PMID: 37286162 DOI: 10.1016/j.neuroscience.2023.05.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 05/17/2023] [Accepted: 05/27/2023] [Indexed: 06/09/2023]
Abstract
Morphine has a strong analgesic effect and is suitable for various types of pain, so it is widely used. But long-term usage of morphine can lead to drug tolerance, which limits its clinical application. The complex mechanisms underlying the development of morphine analgesia into tolerance involve multiple nuclei in the brain. Recent studies reveal the signaling at the cellular and molecular levels as well as neural circuits contributing to morphine analgesia and tolerance in the ventral tegmental area (VTA), which is traditionally considered a critical center of opioid reward and addiction. Existing studies show that dopamine receptors and μ-opioid receptors participate in morphine tolerance through the altered activities of dopaminergic and/or non-dopaminergic neurons in the VTA. Several neural circuits related to the VTA are also involved in the regulation of morphine analgesia and the development of drug tolerance. Reviewing specific cellular and molecular targets and related neural circuits may provide novel precautionary strategies for morphine tolerance.
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Affiliation(s)
- Jihong Wang
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zheng Li
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ye Tu
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Feng Gao
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
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Pautrat A, Al Tannir R, Pernet-Gallay K, Soutrenon R, Vendramini E, Sinniger V, Overton PG, David O, Coizet V. Altered parabrachial nucleus nociceptive processing may underlie central pain in Parkinson's disease. NPJ Parkinsons Dis 2023; 9:78. [PMID: 37236965 DOI: 10.1038/s41531-023-00516-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 04/28/2023] [Indexed: 05/28/2023] Open
Abstract
The presence of central neuropathic pain in Parkinson's disease suggests that the brain circuits that allow us to process pain could be dysfunctional in the disorder. However, there is to date no clear pathophysiological mechanism to explain these symptoms. In this work, we present evidence that the dysfunction of the subthalamic nucleus and/or substantia nigra pars reticulata may impact nociceptive processing in the parabrachial nucleus (PBN), a low level primary nociceptive structure in the brainstem, and induce a cellular and molecular neuro-adaptation in this structure. In rat models of Parkinson's disease with a partial dopaminergic lesion in the substantia nigra compacta, we found that the substantia nigra reticulata showed enhanced nociceptive responses. Such responses were less impacted in the subthalamic nucleus. A total dopaminergic lesion produced an increase in the nociceptive responses as well as an increase of the firing rate in both structures. In the PBN, inhibited nociceptive responses and increased expression of GABAA receptors were found following a total dopaminergic lesion. However, neuro-adaptations at the level of dendritic spine density and post-synaptic density were found in both dopaminergic lesion groups. These results suggest that the molecular changes within the PBN following a larger dopaminergic lesion, such as increased GABAA expression, is a key mechanism to produce nociceptive processing impairment, whilst other changes may protect function after smaller dopaminergic lesions. We also propose that these neuro-adaptations follow increased inhibitory tone from the substantia nigra pars reticulata and may represent the mechanism generating central neuropathic pain in Parkinson's disease.
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Affiliation(s)
- Arnaud Pautrat
- Université Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neurosciences, 38000, Grenoble, France
| | - Racha Al Tannir
- Université Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neurosciences, 38000, Grenoble, France
| | - Karin Pernet-Gallay
- Université Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neurosciences, 38000, Grenoble, France
| | - Rémi Soutrenon
- Université Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neurosciences, 38000, Grenoble, France
| | - Estelle Vendramini
- Université Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neurosciences, 38000, Grenoble, France
| | - Valérie Sinniger
- Université Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neurosciences, 38000, Grenoble, France
| | - Paul G Overton
- Department of Psychology, University of Sheffield, Sheffield, UK
| | - Olivier David
- Université Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neurosciences, 38000, Grenoble, France
- Aix-Marseille Université, Institut National de la Santé et de la Recherche Médicale, Institut de Neurosciences des Systèmes (INS) UMR1106, Marseille, 13005, France
| | - Véronique Coizet
- Université Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut Neurosciences, 38000, Grenoble, France.
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Blockade of the orexin receptors in the ventral tegmental area could attenuate the stress-induced analgesia: A behavioral and molecular study. Prog Neuropsychopharmacol Biol Psychiatry 2023; 120:110639. [PMID: 36116673 DOI: 10.1016/j.pnpbp.2022.110639] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 08/08/2022] [Accepted: 09/12/2022] [Indexed: 11/23/2022]
Abstract
Exposure to stressful stimuli induces various physiological and behavioral responses, affects pain perception, and alters gene expression. Stress elicits an analgesic effect in laboratory animals, termed the "stress-induced analgesia" (SIA). Orexin neuropeptides, processed from pre-pro-orexin in the hypothalamus, release during stress and are known to be antinociceptive. The current study examined the modulatory role of the ventral tegmental area (VTA) orexinergic system in the restraint SIA and extracellular signal-regulated kinase (ERK) activation in the nucleus accumbens (NAc). Adult male Wistar rats were subjected to intra-VTA injection of orexin-1 and -2 receptor antagonists (SB334867 and TCS OX2 29; 1, 3, 10, and 30 nmol/0.3 μl, respectively) five min before a 3-h period of exposure to restraint stress (RS). Western blot analysis was also used to assess the levels of ERK and phosphorylated ERK (p-ERK) in the NAc tissues. RS exposure produced an analgesic response to the thermal pain model (Tail-flick test). RS-induced antinociception was inhibited by intra-VTA administration of SB334867 and TCS OX2 29. Moreover, in the molecular study, exposure to forced swim stress (FSS) and RS significantly enhanced the p-ERK/ERK ratio. Blockade of both orexin receptors diminished the p-ERK/ERK ratio, but this decrease was significant only in the FSS group of animals that received TCS OX2 29. Collectively, the present findings suggested the functional roles of intra-VTA orexin receptors and ERK signaling in the SIA.
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Sardari M, Seddighfar M, Sardari S. Dopamine receptors in the anterior cingulate cortex implicate in nicotine enhanced morphine analgesia. Psychopharmacology (Berl) 2021; 238:3311-3323. [PMID: 34383109 DOI: 10.1007/s00213-021-05947-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 08/02/2021] [Indexed: 11/27/2022]
Abstract
RATIONALE It is well known that the anterior cingulate cortex (ACC) plays an important role in acute pain perception. OBJECTIVES In the present study, we aimed to investigate the possible involvement of the ACC dopamine D1 and D2 receptors in nicotine plus morphine-induced analgesia. METHODS The ACC's of adult male Wistar rats were bilaterally cannulated by stereotaxic instrument and the tail-flick test was used to measure the thermal pain threshold. RESULTS The results indicated that subcutaneous (s.c.) injection of nicotine (0.3 mg/kg) potentiated the analgesic response of intraperitoneal (i.p.) administration of morphine (3 mg/kg). Systemic administration of the same doses of nicotine or morphine alone had no effect on tail-flick latency. Intra-ACC administration of apomorphine (0.3-0.9 μg/rat), the non-selective D1/D2 receptors agonist, plus ineffective doses of nicotine (0.1 mg/kg, s.c.) plus morphine (3 mg/kg, i.p) induced analgesia in rats. In addition, the analgesia induced with co-administration of nicotine and morphine was inhibited via intra-ACC administration of SCH23390 (0.5-1 μg/rat) or sulpiride (0.5-2 μg/rat), the selective antagonists of D1 or D2 receptors, respectively. The intra-ACC microinjection of the same doses of drugs alone had no effect on tail-flick latency. Cubic interpolation analysis also confirmed that activation or inactivation of the ACC D1 and D2 receptors by different doses of drugs can modulate the nicotine-morphine analgesic response. CONCLUSIONS The findings suggest that the ACC has an important role in acute thermal pain perception and modulates the analgesia induced by nicotine plus morphine via dopaminergic receptors.
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Affiliation(s)
- Maryam Sardari
- Department of Animal Biology, School of Biology and Center of Excellence in Phylogeny of Living Organisms, College of Science, University of Tehran, P. O. Box 4155-6455, Tehran, Iran.
| | - Masoud Seddighfar
- Department of Animal Biology, School of Biology and Center of Excellence in Phylogeny of Living Organisms, College of Science, University of Tehran, P. O. Box 4155-6455, Tehran, Iran
| | - Sara Sardari
- Department of Computer Science and Engineering, Shiraz University, Shiraz, Iran
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The Role of Mesostriatal Dopamine System and Corticostriatal Glutamatergic Transmission in Chronic Pain. Brain Sci 2021; 11:brainsci11101311. [PMID: 34679376 PMCID: PMC8533867 DOI: 10.3390/brainsci11101311] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 09/28/2021] [Accepted: 10/01/2021] [Indexed: 12/21/2022] Open
Abstract
There is increasing recognition of the involvement of the nigrostriatal and mesolimbic dopamine systems in the modulation of chronic pain. The first part of the present article reviews the evidence indicating that dopamine exerts analgesic effects during persistent pain by stimulating the D2 receptors in the dorsal striatum and nucleus accumbens (NAc). Thereby, dopamine inhibits striatal output via the D2 receptor-expressing medium spiny neurons (D2-MSN). Dopaminergic neurotransmission in the mesostriatal pathways is hampered in chronic pain states and this alteration maintains and exacerbates pain. The second part of this article focuses on the glutamatergic inputs from the medial prefrontal cortex to the NAc, their activity changes in chronic pain, and their role in pain modulation. Finally, interactions between dopaminergic and glutamatergic inputs to the D2-MSN are considered in the context of persistent pain. Studies using novel techniques indicate that pain is regulated oppositely by two independent dopaminergic circuits linking separate parts of the ventral tegmental area and of the NAc, which also interact with distinct regions of the medial prefrontal cortex.
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Yu W, Pati D, Pina MM, Schmidt KT, Boyt KM, Hunker AC, Zweifel LS, McElligott ZA, Kash TL. Periaqueductal gray/dorsal raphe dopamine neurons contribute to sex differences in pain-related behaviors. Neuron 2021; 109:1365-1380.e5. [PMID: 33740416 PMCID: PMC9990825 DOI: 10.1016/j.neuron.2021.03.001] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 02/02/2021] [Accepted: 02/26/2021] [Indexed: 02/06/2023]
Abstract
Sex differences in pain severity, response, and pathological susceptibility are widely reported, but the neural mechanisms that contribute to these outcomes remain poorly understood. Here we show that dopamine (DA) neurons in the ventrolateral periaqueductal gray/dorsal raphe (vlPAG/DR) differentially regulate pain-related behaviors in male and female mice through projections to the bed nucleus of the stria terminalis (BNST). We find that activation of vlPAG/DRDA+ neurons or vlPAG/DRDA+ terminals in the BNST reduces nociceptive sensitivity during naive and inflammatory pain states in male mice, whereas activation of this pathway in female mice leads to increased locomotion in the presence of salient stimuli. We additionally use slice physiology and genetic editing approaches to demonstrate that vlPAG/DRDA+ projections to the BNST drive sex-specific responses to pain through DA signaling, providing evidence of a novel ascending circuit for pain relief in males and contextual locomotor response in females.
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Affiliation(s)
- Waylin Yu
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Dipanwita Pati
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Melanie M Pina
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Karl T Schmidt
- Department of Psychiatry, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Kristen M Boyt
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Avery C Hunker
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Larry S Zweifel
- Department of Pharmacology, University of Washington, Seattle, WA 98195, USA; Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA 98195, USA
| | - Zoe A McElligott
- Department of Psychiatry, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Thomas L Kash
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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Ferrari LF, Pei J, Zickella M, Rey C, Zickella J, Ramirez A, Taylor NE. D2 Receptors in the Periaqueductal Gray/Dorsal Raphe Modulate Peripheral Inflammatory Hyperalgesia via the Rostral Ventral Medulla. Neuroscience 2021; 463:159-173. [PMID: 33826955 DOI: 10.1016/j.neuroscience.2021.03.035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 03/24/2021] [Accepted: 03/29/2021] [Indexed: 11/19/2022]
Abstract
Dopamine neurons in the periaqueductal gray (PAG)/dorsal raphe are key modulators of antinociception with known supraspinal targets. However, no study has directly tested whether these neurons contribute to descending pain inhibition. We hypothesized that PAG dopamine neurons contribute to the analgesic effect of D-amphetamine via a mechanism that involves descending modulation via the rostral ventral medulla (RVM). Male C57BL/6 mice showed increased c-FOS expression in PAG dopamine neurons and a significant increase in paw withdrawal latency to thermal stimulation after receiving a systemic injection of D-amphetamine. Targeted microinfusion of D-amphetamine, L-DOPA, or the selective D2 agonist quinpirole into the PAG produced analgesia, while a D1 agonist, chloro APB, had no effect. In addition, inhibition of D2 receptors in the PAG by eticlopride prevented the systemic D-amphetamine analgesic effect. D-amphetamine and PAG D2 receptor-mediated analgesia were inhibited by intra-RVM injection of lidocaine or the GABAA receptor agonist muscimol, indicating a PAG-RVM signaling pathway in this model of analgesia. Finally, both systemic D-amphetamine and local PAG microinjection of quinpirole, inhibited inflammatory hyperalgesia induced by carrageenan. This hyperalgesia was transiently restored by intra-PAG injection of eticlopride, as well as RVM microinjection of muscimol. We conclude that D-amphetamine analgesia is partially mediated by descending inhibition and that D2 receptors in the PAG are responsible for this effect via modulating neurons that project to the RVM. These results further our understanding of the antinociceptive effects of dopamine and elucidate a mechanism by which clinically available dopamine modulators produce analgesia.
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Affiliation(s)
- Luiz F Ferrari
- Department of Anesthesiology, University of Utah School of Medicine, 30 N 1900 E, RM 3C444 SOM, Salt Lake City, UT 84132, United States.
| | - JunZhu Pei
- Department of Biomedical Engineering, Florida International University, United States.
| | - Michael Zickella
- Department of Anesthesiology, University of Utah School of Medicine, 30 N 1900 E, RM 3C444 SOM, Salt Lake City, UT 84132, United States
| | - Charles Rey
- Department of Anesthesiology, University of Utah School of Medicine, 30 N 1900 E, RM 3C444 SOM, Salt Lake City, UT 84132, United States
| | - Jacqueline Zickella
- Department of Anesthesiology, University of Utah School of Medicine, 30 N 1900 E, RM 3C444 SOM, Salt Lake City, UT 84132, United States
| | - Anna Ramirez
- Department of Anesthesiology, University of Utah School of Medicine, 30 N 1900 E, RM 3C444 SOM, Salt Lake City, UT 84132, United States.
| | - Norman E Taylor
- Department of Anesthesiology, University of Utah School of Medicine, 30 N 1900 E, RM 3C444 SOM, Salt Lake City, UT 84132, United States.
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Matini T, Haghparast A, Rezaee L, Salehi S, Tehranchi A, Haghparast A. Role of Dopaminergic Receptors Within the Ventral Tegmental Area in Antinociception Induced by Chemical Stimulation of the Lateral Hypothalamus in an Animal Model of Orofacial Pain. J Pain Res 2020; 13:1449-1460. [PMID: 32606911 PMCID: PMC7304680 DOI: 10.2147/jpr.s255250] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 06/03/2020] [Indexed: 12/13/2022] Open
Abstract
Introduction The ventral tegmental area (VTA), as one of the classical components of the brain reward circuitry, shares large neural networks with the pain processing system. We previously showed the role of VTA dopamine receptors in modulation of lateral hypothalamus (LH)-induced antinociception in acute pain conditions. However, considering the fact that the neural systems involved in the mediation of tonic pain are not the same as those that mediate phasic pain. In the present study, we aimed to examine the role of intra-VTA dopamine receptors in LH-induced antinociceptive responses during tonic orofacial pain conditions. Methods Male Wistar rats weighing 230-250 g were implanted with two separate cannulae into the LH and VTA on the same side. Different solutions of carbachol (62.5, 125 and 250 nM), as a non-selective cholinergic receptor agonist that activates the LH projecting neurons, were microinjected into the LH. In the other groups, D1-like dopamine receptor antagonist, SCH-23390 (0.25, 1 and 4 µg/03 µL saline) or D2-like dopamine receptor antagonist, Sulpiride (0.25, 1 and 4 µg/0.3 µL DMSO 12%) were microinjected into VTA, 5 min prior intra-LH carbachol (250 nM), then subjected to orofacial formalin test. Intra-LH carbachol microinjection dose-dependently attenuated biphasic orofacial pain. Results Intra-VTA administration of SCH-23390 or Sulpiride dose-dependently decreased intra-LH carbachol-induced antinociception during both phases of orofacial formalin test with further effects in the late phase. Discussion The findings suggest that chemical stimulation of the LH by carbachol possibly activates the orexin projecting neurons and subsequently, the VTA dopaminergic neurons involved in the orofacial pain modulation. Detecting such neural circuitry offers an alternative approach in the development of more efficient therapies for such debilitating pain conditions.
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Affiliation(s)
- Tina Matini
- School of Dentistry, International Branch of Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Amir Haghparast
- School of Dentistry, International Branch of Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Laleh Rezaee
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Sakineh Salehi
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Department of Medicine, Ardabil Medical Sciences Branch, Islamic Azad University, Ardabil, Iran
| | - Azita Tehranchi
- Dental Research Center, Research Institute of Dental Sciences, Dental School, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Abbas Haghparast
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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The Cataleptic, Asymmetric, Analgesic, and Brain Biochemical Effects of Parkinson's Disease Can Be Affected by Toxoplasma gondii Infection. BIOMED RESEARCH INTERNATIONAL 2020; 2020:2546365. [PMID: 32461971 PMCID: PMC7222602 DOI: 10.1155/2020/2546365] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Accepted: 03/18/2020] [Indexed: 02/07/2023]
Abstract
Purpose Parkinson's disease (PD) is a neurodegenerative disorder with progressive motor defects. Therefore, the aim of the present investigation was to examine whether catalepsy, asymmetry, and nociceptive behaviors; the Nissl-body and neuron distribution; brain-derived neurotrophic factor (BDNF); malondialdehyde (MDA); total antioxidant capacity (TAC) levels; and the percentage of dopamine depletion of striatal neurons in the rat model of Parkinson's disease (PD) can be affected by Toxoplasma gondii (TG) infection. Methods Fifty rats were divided into five groups: control (intact rats), sham (rats which received an intrastriatal injection of artificial cerebrospinal fluid (ACSF)), PD control (induction of PD without TG infection), TG control (rats infected by TG without PD induction), and PD infected (third week after PD induction, infection by TG was done). PD was induced by the unilateral intrastriatal microinjection of 6-hydroxydopamine (6-OHDA) and ELISA quantified dopamine, BDNF, MDA, and TAC in the striatum tissue. Cataleptic, asymmetrical, nociceptive, and histological alterations were determined by bar test, elevated body swing test, formalin test, and Nissl-body and neuron counting in the striatal neurons. Results The results demonstrated that PD could significantly increase the number of biased swings, descent latency time, and nociceptive behavior and decrease the distribution of Nissl-stained neurons compared to the control and sham groups. TG infection significantly improved biased swing, descent latency time, nociceptive behavior, and the Nissl-body distribution in striatal neurons in comparison to the PD control group. The striatal level of BDNF in the PD-infected and TG control groups significantly increased relative to the PD control group. The striatal MDA was significantly higher in the PD control than other groups, while striatal TAC was significantly lower in the PD control than other groups. Conclusions The current study indicates that TG infection could improve the cataleptic, asymmetric, nociceptive and behaviors; the level of striatal dopamine release; BDNF levels; TAC; and MDA in PD rats.
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Alijanpour S, Zarrindast MR. Potentiation of morphine-induced antinociception by harmaline: involvement of μ-opioid and ventral tegmental area NMDA receptors. Psychopharmacology (Berl) 2020; 237:557-570. [PMID: 31740992 DOI: 10.1007/s00213-019-05389-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Accepted: 11/04/2019] [Indexed: 12/23/2022]
Abstract
RATIONAL Morphine is one of the most well-known and potent analgesic agents; however, it can also induce various side effects. Thus, finding drugs and mechanisms which can potentiate the analgesic effects of low doses of morphine will be a good strategy for pain management. OBJECTIVE The involvement of μ-opioid receptors and ventral tegmental area (VTA) glutamatergic system in harmaline and morphine combination on the nociceptive response were investigated. Also, we examined reward efficacy and tolerance expression following the drugs. METHODS Animals were bilaterally cannulated in the VTA by stereotaxic instrument. A tail-flick (TF) apparatus and conditioned place preference (CPP) paradigm were used to measure nociceptive response and rewarding effects in male NMRI mice respectively. RESULTS Morphine (2 mg/kg, i.p.) had no effect in TF test. Also, harmaline (1.25 and 5 mg/kg, i.p.) could not change pain threshold. Combination of a non-effective dose of harmaline (5 mg/kg) and morphine (2 mg/kg) produced antinociception and also prevented morphine tolerance but had no effect on the acquisition of CPP. Systemic administration of naloxone (0.5 and 1 mg/kg) and intra-VTA microinjection of NMDA (0.06 and 0.1 μg/mouse) before harmaline (5 mg/kg) plus morphine (2 mg/kg) prevented antinociception induced by the drugs. D-AP5 (0.5 and 1 μg/mouse, intra-VTA) potentiated the effect of low-dose harmaline (1.25 mg/kg) and morphine (2 mg/kg) and induced antinociception. Microinjection of the same doses of NMDA or D-AP5 into the VTA alone had no effect on pain threshold. CONCLUSION The findings showed that harmaline potentiated the analgesic effect of morphine and reduced morphine tolerance. Glutamatergic and μ-opioidergic system interactions in the VTA seem to have a modulatory role in harmaline plus morphine-induced analgesia.
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Affiliation(s)
- Sakineh Alijanpour
- Department of Biology, Faculty of Science, Gonbad Kavous University, P. O. Box 163, Gonbad Kavous, Iran.
| | - Mohammad-Reza Zarrindast
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.,Iranian National Center for Addiction Studies, Tehran University of Medical Sciences, Tehran, Iran.,Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran
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Brewer R, Blum K, Bowirrat A, Modestino EJ, Baron D, Badgaiyan RD, Moran M, Boyett B, Gold MS. Transmodulation of Dopaminergic Signaling to Mitigate Hypodopminergia and Pharmaceutical Opioid-Induced Hyperalgesia. CURRENT PSYCHOPHARMACOLOGY 2020; 9:164-184. [PMID: 37361136 PMCID: PMC10288629 DOI: 10.2174/2211556009999200628093231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 04/16/2020] [Accepted: 05/06/2020] [Indexed: 06/28/2023]
Abstract
Neuroscientists and psychiatrists working in the areas of "pain and addiction" are asked in this perspective article to reconsider the current use of dopaminergic blockade (like chronic opioid agonist therapy), and instead to consider induction of dopamine homeostasis by putative pro-dopamine regulation. Pro-dopamine regulation could help pharmaceutical opioid analgesic agents to mitigate hypodopaminergia-induced hyperalgesia by inducing transmodulation of dopaminergic signaling. An optimistic view is that early predisposition to diagnosis based on genetic testing, (pharmacogenetic/pharmacogenomic monitoring), combined with appropriate urine drug screening, and treatment with pro-dopamine regulators, could conceivably reduce stress, craving, and relapse, enhance well-being and attenuate unwanted hyperalgesia. These concepts require intensive investigation. However, based on the rationale provided herein, there is a good chance that combining opioid analgesics with genetically directed pro-dopamine-regulation using KB220 (supported by 43 clinical studies). This may become a front-line technology with the potential to overcome, in part, the current heightened rates of chronic opioid-induced hyperalgesia and concomitant Reward Deficiency Syndrome (RDS) behaviors. Current research does support the hypothesis that low or hypodopaminergic function in the brain may predispose individuals to low pain tolerance or hyperalgesia.
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Affiliation(s)
- Raymond Brewer
- Department of Nutrigenomics, Genomic Testing Center, Geneus Health, LLC., San Antonio, TX, USA
| | - Kenneth Blum
- Department of Nutrigenomics, Genomic Testing Center, Geneus Health, LLC., San Antonio, TX, USA
- Western University Health Sciences, Pomona, CA., USA
- Division of Neuroscience and Addiction Research, Pathway Healthcare, Birmingham, AL, USA
- Eotvos Loránd University, Institute of Psychology, Budapest, Hungary
- Department of Psychiatry, Wright State University Boonshoft School of Medicine and Dayton VA Medical Center, Dayton, OH, USA
- Department of Psychiatry, University of Vermont, Burlington, VT., USA
| | - Abdalla Bowirrat
- Department of Neuroscience and Genetics, Interdisciplinary Center Herzliya, Israel
| | | | - David Baron
- Western University Health Sciences, Pomona, CA., USA
| | - Rajendra D. Badgaiyan
- Department of Psychiatry, ICHAN School of Medicine, Mount Sinai, New York, NYC. & Department of Psychiatry, South Texas Veteran Health Care System, Audie L. Murphy Memorial VA Hospital, San Antonio, TX, Long School of Medicine, University of Texas Medical Center, San Antonio, TX, USA
| | - Mark Moran
- Department of Nutrigenomics, Genomic Testing Center, Geneus Health, LLC., San Antonio, TX, USA
| | - Brent Boyett
- Division of Neuroscience and Addiction Research, Pathway Healthcare, Birmingham, AL, USA
- Bradford Health Services, Madison, AL., USA
| | - Mark S. Gold
- Department of Psychiatry, Washington University School of Medicine, St. Louis, Mo., USA
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Taylor NE, Pei J, Zhang J, Vlasov KY, Davis T, Taylor E, Weng FJ, Van Dort CJ, Solt K, Brown EN. The Role of Glutamatergic and Dopaminergic Neurons in the Periaqueductal Gray/Dorsal Raphe: Separating Analgesia and Anxiety. eNeuro 2019; 6:ENEURO.0018-18.2019. [PMID: 31058210 PMCID: PMC6498422 DOI: 10.1523/eneuro.0018-18.2019] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 01/08/2019] [Accepted: 01/29/2019] [Indexed: 12/23/2022] Open
Abstract
The periaqueductal gray (PAG) is a significant modulator of both analgesic and fear behaviors in both humans and rodents, but the underlying circuitry responsible for these two phenotypes is incompletely understood. Importantly, it is not known if there is a way to produce analgesia without anxiety by targeting the PAG, as modulation of glutamate or GABA neurons in this area initiates both antinociceptive and anxiogenic behavior. While dopamine (DA) neurons in the ventrolateral PAG (vlPAG)/dorsal raphe display a supraspinal antinociceptive effect, their influence on anxiety and fear are unknown. Using DAT-cre and Vglut2-cre male mice, we introduced designer receptors exclusively activated by designer drugs (DREADD) to DA and glutamate neurons within the vlPAG using viral-mediated delivery and found that levels of analgesia were significant and quantitatively similar when DA and glutamate neurons were selectively stimulated. Activation of glutamatergic neurons, however, reliably produced higher indices of anxiety, with increased freezing time and more time spent in the safety of a dark enclosure. In contrast, animals in which PAG/dorsal raphe DA neurons were stimulated failed to show fear behaviors. DA-mediated antinociception was inhibitable by haloperidol and was sufficient to prevent persistent inflammatory pain induced by carrageenan. In summary, only activation of DA neurons in the PAG/dorsal raphe produced profound analgesia without signs of anxiety, indicating that PAG/dorsal raphe DA neurons are an important target involved in analgesia that may lead to new treatments for pain.
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Affiliation(s)
| | - JunZhu Pei
- Massachusetts Institute of Technology, Cambridge 02139, MA
| | - Jie Zhang
- University of Utah, Salt Lake City 84112, UT
| | | | | | - Emma Taylor
- University of Massachusetts, Lowell 01854, MA
| | - Feng-Ju Weng
- Massachusetts Institute of Technology, Cambridge 02139, MA
| | | | - Ken Solt
- Massachusetts General Hospital, Boston 02114, MA
| | - Emery N Brown
- Massachusetts General Hospital, Boston 02114, MA
- Massachusetts General Hospital, Boston 02114, MA
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Faivre F, Joshi A, Bezard E, Barrot M. The hidden side of Parkinson’s disease: Studying pain, anxiety and depression in animal models. Neurosci Biobehav Rev 2019; 96:335-352. [DOI: 10.1016/j.neubiorev.2018.10.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 09/14/2018] [Accepted: 10/12/2018] [Indexed: 12/21/2022]
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16
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Taylor AM. Corticolimbic circuitry in the modulation of chronic pain and substance abuse. Prog Neuropsychopharmacol Biol Psychiatry 2018; 87:263-268. [PMID: 28501595 PMCID: PMC5681440 DOI: 10.1016/j.pnpbp.2017.05.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 04/14/2017] [Accepted: 05/10/2017] [Indexed: 12/13/2022]
Abstract
The transition from acute to chronic pain is accompanied by increased engagement of emotional and motivational circuits. Adaptations within this corticolimbic circuitry contribute to the cellular and behavioral maladaptations associated with chronic pain. Central regions within the corticolimbic brain include the mesolimbic dopamine system, the amygdala, and the medial prefrontal cortex. The evidence reviewed herein supports the notion that chronic pain induces significant changes within these corticolimbic regions that contribute to the chronicity and intractability of pain. In addition, pain-induced changes in corticolimbic circuitry are poised to impact motivated behavior and reward responsiveness to environmental stimuli, and may modulate the addiction liability of drugs of abuse, such as opioids.
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Affiliation(s)
- Anna M.W. Taylor
- Department of Psychiatry and the Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles
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Blanchet PJ, Brefel-Courbon C. Chronic pain and pain processing in Parkinson's disease. Prog Neuropsychopharmacol Biol Psychiatry 2018; 87:200-206. [PMID: 29031913 DOI: 10.1016/j.pnpbp.2017.10.010] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 09/26/2017] [Accepted: 10/07/2017] [Indexed: 12/24/2022]
Abstract
Pain is experienced by the vast majority of patients living with Parkinson's disease. It is most often of nociceptive origin, but may also be ascribed to neuropathic (radicular or central) or miscellaneous sources. The recently validated King's Parkinson's Disease Pain Scale is based on 7 domains including musculoskeletal pain, chronic body pain (central or visceral), fluctuation-related pain, nocturnal pain, oro-facial pain, pain with discolouration/oedema/swelling, and radicular pain. The basal ganglia integrate incoming nociceptive information and contribute to coordinated motor responses in pain avoidance and nocifensive behaviors. In Parkinson's disease, nigral and extra-nigral pathology, involving cortical areas, brainstem nuclei, and spinal cord, may contribute to abnormal central nociceptive processing in patients experiencing pain or not. The dopamine deficit lowers multimodal pain thresholds that are amenable to correction following levodopa dosing. Functional brain imaging with positron emission tomography following administration of H215O revealed abnormalities in the sensory discriminative processing of pain (insula/SII), as well as in the affective motivational processing of pain (anterior cingulate cortex, prefrontal cortex). Pain management is dependent on efforts invested in diagnostic accuracy to distinguish nociceptive from neuropathic pain. Treatment requires an integrated approach including strategies to lessen levodopa-related response fluctuations, in addition to other pharmacological and non-pharmacological options such as deep brain stimulation and rehabilitation.
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Affiliation(s)
- Pierre J Blanchet
- Department of Stomatology, Faculty of Dental Medicine, Université de Montréal; Montréal, QC, Canada; Service de neurologie, CHU Montréal, Montréal, QC, Canada.
| | - Christine Brefel-Courbon
- Service de Pharmacologie Clinique, Faculty of Medicine, University Hospital, Toulouse, France; Service de neurologie B8, Pierre Paul Riquet Hospital, University Hospital, Toulouse, France.
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18
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Shafiei I, Vatankhah M, Zarepour L, Ezzatpanah S, Haghparast A. Role of D1- and D2-like dopaminergic receptors in the nucleus accumbens in modulation of formalin-induced orofacial pain: Involvement of lateral hypothalamus. Physiol Behav 2018; 188:25-31. [DOI: 10.1016/j.physbeh.2018.01.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 01/24/2018] [Accepted: 01/24/2018] [Indexed: 11/16/2022]
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19
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Thobois S, Brefel-Courbon C, Le Bars D, Sgambato-Faure V. Molecular Imaging of Opioid System in Idiopathic Parkinson's Disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2018; 141:275-303. [DOI: 10.1016/bs.irn.2018.07.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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20
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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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21
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Boadas-Vaello P, Homs J, Reina F, Carrera A, Verdú E. Neuroplasticity of Supraspinal Structures Associated with Pathological Pain. Anat Rec (Hoboken) 2017; 300:1481-1501. [PMID: 28263454 DOI: 10.1002/ar.23587] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 09/27/2016] [Accepted: 10/18/2016] [Indexed: 12/19/2022]
Abstract
Peripheral nerve and spinal cord injuries, along with other painful syndromes such as fibromyalgia, diabetic neuropathy, chemotherapeutic neuropathy, trigeminal neuralgia, complex regional pain syndrome, and/or irritable bowel syndrome, cause several neuroplasticity changes in the nervous system along its entire axis affecting the different neuronal nuclei. This paper reviews these changes, focusing on the supraspinal structures that are involved in the modulation and processing of pain, including the periaqueductal gray matter, red nucleus, locus coeruleus, rostral ventromedial medulla, thalamus, hypothalamus, basal ganglia, cerebellum, habenula, primary, and secondary somatosensory cortex, motor cortex, mammillary bodies, hippocampus, septum, amygdala, cingulated, and prefrontal cortex. Hyperexcitability caused by the modification of postsynaptic receptor expression, central sensitization, and potentiation of presynaptic delivery of neurotransmitters, as well as the reduction of inhibitory inputs, changes in dendritic spine, neural circuit remodeling, alteration of gray matter, and upregulation of proinflammatory mediators (e.g., cytokines) by reactivation of astrocytes and microglial cells are the main functional, structural, and molecular neuroplasticity changes observed in the above supraspinal structures, associated with pathological pain. Studying these changes in greater depth may lead to the implementation and improvement of new therapeutic strategies against pathological pain. Anat Rec, 300:1481-1501, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Pere Boadas-Vaello
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, Faculty of Medicine, Universitat de Girona, Girona, Catalonia, 17003, Spain
| | - Judit Homs
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, Faculty of Medicine, Universitat de Girona, Girona, Catalonia, 17003, Spain.,Department of Physical Therapy EUSES-Universitat of Girona, Salt (Girona), Catalonia, 17190, Spain
| | - Francisco Reina
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, Faculty of Medicine, Universitat de Girona, Girona, Catalonia, 17003, Spain
| | - Ana Carrera
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, Faculty of Medicine, Universitat de Girona, Girona, Catalonia, 17003, Spain
| | - Enrique Verdú
- Research Group of Clinical Anatomy, Embryology and Neuroscience (NEOMA), Department of Medical Sciences, Faculty of Medicine, Universitat de Girona, Girona, Catalonia, 17003, Spain
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Cahill CM, Taylor AM. Neuroinflammation-a co-occurring phenomenon linking chronic pain and opioid dependence. Curr Opin Behav Sci 2017; 13:171-177. [PMID: 28451629 DOI: 10.1016/j.cobeha.2016.12.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Chronic pain is a disease that encompasses both sensory and emotional elements. Opioids are highly effective analgesics because they target both of these elements, by inhibiting pain pathways and alleviating negative affect (including depression) by engaging reward or hedonic pathways. Unfortunately, chronic opioid use is limited by the development of unwanted side effects, such as tolerance, hyperalgesia, and abuse liability. Thus, the challenge of providing effective pain treatment while minimizing these unwanted side effects is an ongoing issue with significant clinical and societal impact. In this review, we posit that neuroinflammation within the central nervous system is a shared phenomenon between chronic pain and opioids that contributes to pain sensitization and negative affect. The implications for pain progression, addiction liability, and alternative treatment strategies are discussed.
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Affiliation(s)
- Catherine M Cahill
- Department of Anesthesiology and Perioperative Care, University of California, Irvine 837 Health Sciences Road, Irvine, CA 90095, USA.,Department of Biomedical and Molecular Sciences, Queen's University, 5117 Botterell Hall, Kingston, Ontario K7L 3N6, Canada
| | - Anna Mw Taylor
- Hatos Center for Neuropharmacology, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles 675 Charles E Young Drive South, Los Angeles, CA 90095, USA
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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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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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Stimulation of the ventral tegmental area increased nociceptive thresholds and decreased spinal dorsal horn neuronal activity in rat. Exp Brain Res 2016; 234:1505-14. [PMID: 26821313 DOI: 10.1007/s00221-016-4558-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 01/09/2016] [Indexed: 12/30/2022]
Abstract
Deep brain stimulation has been found to be effective in relieving intractable pain. The ventral tegmental area (VTA) plays a role not only in the reward process, but also in the modulation of nociception. Lesions of VTA result in increased pain thresholds and exacerbate pain in several pain models. It is hypothesized that direct activation of VTA will reduce pain experience. In this study, we investigated the effect of direct electrical stimulation of the VTA on mechanical, thermal and carrageenan-induced chemical nociceptive thresholds in Sprague-Dawley rats using our custom-designed wireless stimulator. We found that: (1) VTA stimulation itself did not show any change in mechanical or thermal threshold; and (2) the decreased mechanical and thermal thresholds induced by carrageenan injection in the hind paw contralateral to the stimulation site were significantly reversed by VTA stimulation. To further explore the underlying mechanism of VTA stimulation-induced analgesia, spinal cord dorsal horn neuronal responses to graded mechanical stimuli were recorded. VTA stimulation significantly inhibited dorsal horn neuronal activity in response to pressure and pinch from the paw, but not brush. This indicated that VTA stimulation may have exerted its analgesic effect via descending modulatory pain pathways, possibly through its connections with brain stem structures and cerebral cortex areas.
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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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Doubling Your Payoff: Winning Pain Relief Engages Endogenous Pain Inhibition. eNeuro 2015; 2:eN-NWR-0029-15. [PMID: 26464995 PMCID: PMC4596013 DOI: 10.1523/eneuro.0029-15.2015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 08/18/2015] [Accepted: 08/19/2015] [Indexed: 01/07/2023] Open
Abstract
When in pain, pain relief is much sought after, particularly for individuals with chronic pain. In analogy to augmentation of the hedonic experience (“liking”) of a reward by the motivation to obtain a reward (“wanting”), the seeking of pain relief in a motivated state might increase the experience of pain relief when obtained. We tested this hypothesis in a psychophysical experiment in healthy human subjects, by assessing potential pain-inhibitory effects of pain relief “won” in a wheel of fortune game compared with pain relief without winning, exploiting the fact that the mere chance of winning induces a motivated state. The results show pain-inhibitory effects of pain relief obtained by winning in behaviorally assessed pain perception and ratings of pain intensity. Further, the higher participants scored on the personality trait novelty seeking, the more pain inhibition was induced. These results provide evidence that pain relief, when obtained in a motivated state, engages endogenous pain-inhibitory systems beyond the pain reduction that underlies the relief in the first place. Consequently, such pain relief might be used to improve behavioral pain therapy, inducing a positive, perhaps self-amplifying feedback loop of reduced pain and improved functionality.
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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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Sadeghi S, Reisi Z, Azhdari-Zarmehri H, Haghparast A. Involvement of orexin-1 receptors in the ventral tegmental area and the nucleus accumbens in antinociception induced by lateral hypothalamus stimulation in rats. Pharmacol Biochem Behav 2013; 105:193-8. [DOI: 10.1016/j.pbb.2013.02.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 02/17/2013] [Accepted: 02/20/2013] [Indexed: 10/27/2022]
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Blum K, Han D, Oscar-Berman M, Reinl G, DiNubile N, Madigan MA, Bajaj A, Downs BW, Giordano J, Westcott W, Smith L, Braverman ER, Dushaj K, Hauser M, Simpatico T, McLaughlin T, Borsten J, Barh D. Iatrogenic opioid dependence is endemic and legal: Genetic addiction risk score (GARS) with electrotherapy a paradigm shift in pain treatment programs. Health (London) 2013. [DOI: 10.4236/health.2013.511a1004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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YAMAMOTOVÁ A, ŠLAMBEROVÁ R. Behavioral and Antinociceptive Effects of Different Psychostimulant Drugs in Prenatally Methamphetamine-Exposed Rats. Physiol Res 2012; 61:S139-47. [DOI: 10.33549/physiolres.932428] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Prenatal exposure to methamphetamine (METH) increases nociceptive sensitivity in adult rats. As the strong analgesics have high abuse potential and drugs of abuse are known to have analgesic properties, the aim was to study analgesic effect of different psychostimulants in control and prenatally METH-exposed rats. Latencies of withdrawal reflexes of hind limbs and the tail on thermal nociceptive stimuli were repeatedly measured in 15-min intervals after the application of 5 mg/kg s.c. of amphetamine (AMPH), methamphetamine (METH), cocaine (COC), 3,4-methylenedioxymethamphetamine (MDMA) or morphine (MOR). In all groups, AMPH induced on hind limbs stronger analgesia than METH and MDMA whereas COC and MOR were practically without any effect. On the tail, effect of AMPH did not differ from that of MOR. All psychostimulants increased defecation in comparison with MOR and in all groups the number of defecation boluses positively correlated with analgesia of the hind limbs. We did not confirm that prenatal exposure to METH makes adult rats more sensitive either to same drug or to other psychostimulants. The different analgesic potencies of psychostimulants and MOR at different body sites indicate the possible existence of a somatotopic organization of pain inhibition, which is controlled by different mechanisms.
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Affiliation(s)
- A. YAMAMOTOVÁ
- Department of Normal, Pathological and Clinical Physiology, Third Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
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Sandner G, Meyer L, Angst MJ, Guignard B, Guiberteau T, Mensah-Nyagan AG. Neonatal ventral hippocampal lesions modify pain perception and evoked potentials in rats. Behav Brain Res 2012; 234:167-74. [DOI: 10.1016/j.bbr.2012.06.026] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Revised: 06/20/2012] [Accepted: 06/22/2012] [Indexed: 01/27/2023]
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Li T, Hou Y, Cao W, Yan CX, Chen T, Li SB. Role of dopamine D3 receptors in basal nociception regulation and in morphine-induced tolerance and withdrawal. Brain Res 2012; 1433:80-4. [DOI: 10.1016/j.brainres.2011.11.045] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Revised: 10/25/2011] [Accepted: 11/19/2011] [Indexed: 10/14/2022]
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Omelchenko N, Sesack SR. Periaqueductal gray afferents synapse onto dopamine and GABA neurons in the rat ventral tegmental area. J Neurosci Res 2010; 88:981-91. [PMID: 19885830 DOI: 10.1002/jnr.22265] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The midbrain central gray (periaqueductal gray; PAG) mediates defensive behaviors and is implicated in the rewarding effects of opiate drugs. Projections from the PAG to the ventral tegmental area (VTA) suggest that this region might also regulate behaviors involving motivation and cognition. However, studies have not yet examined the morphological features of PAG axons in the VTA or whether they synapse onto dopamine (DA) or GABA neurons. In this study, we injected anterograde tracers into the rat PAG and used immunoperoxidase to visualize the projections to the VTA. Immunogold-silver labeling for tyrosine hydroxylase (TH) or GABA was then used to identify the phenotype of innervated cells. Electron microscopic examination of the VTA revealed axons labeled anterogradely from the PAG, including myelinated and unmyelinated fibers and axon varicosities, some of which formed identifiable synapses. Approximately 55% of these synaptic contacts were of the symmetric (presumably inhibitory) type; the rest were asymmetric (presumably excitatory). These findings are consistent with the presence of both GABA and glutamate projection neurons in the PAG. Some PAG axons contained dense-cored vesicles indicating the presence of neuropeptides in addition to classical neurotransmitters. PAG projections synapsed onto both DA and GABA cells with no obvious selectivity, providing the first anatomical evidence for these direct connections. The results suggest a diverse nature of PAG physiological actions on midbrain neurons. Moreover, as both the VTA and PAG are implicated in the reinforcing actions of opiates, our findings provide a potential substrate for some of the rewarding effects of these drugs.
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Affiliation(s)
- Natalia Omelchenko
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
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Zhu J, Chen Y, Lai J, Dang Y, Yan C, Xu M, Chen T. Dopamine D3 receptor regulates basal but not amphetamine-induced changes in pain sensitivity in mice. Neurosci Lett 2010; 477:134-7. [DOI: 10.1016/j.neulet.2010.04.049] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 04/20/2010] [Accepted: 04/20/2010] [Indexed: 11/16/2022]
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Potvin S, Grignon S, Marchand S. Human evidence of a supra-spinal modulating role of dopamine on pain perception. Synapse 2009; 63:390-402. [DOI: 10.1002/syn.20616] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Chen ALC, Chen TJH, Waite RL, Reinking J, Tung HL, Rhoades P, Downs BW, Braverman E, Braverman D, Kerner M, Blum SH, DiNubile N, Smith D, Oscar-Berman M, Prihoda TJ, Floyd JB, O'Brien D, Liu HH, Blum K. Hypothesizing that brain reward circuitry genes are genetic antecedents of pain sensitivity and critical diagnostic and pharmacogenomic treatment targets for chronic pain conditions. Med Hypotheses 2008; 72:14-22. [PMID: 18951726 DOI: 10.1016/j.mehy.2008.07.059] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2008] [Revised: 07/14/2008] [Accepted: 07/16/2008] [Indexed: 11/28/2022]
Abstract
While it is well established that the principal ascending pathways for pain originate in the dorsal horn of the spinal cord and in the medulla, the control and sensitivity to pain may reside in additional neurological loci, especially in the mesolimbic system of the brain (i.e., a reward center), and a number of genes and associated polymorphisms may indeed impact pain tolerance and or sensitivity. It is hypothesized that these polymorphisms associate with a predisposition to intolerance or tolerance to pain. It is further hypothesized that identification of certain gene polymorphisms provides a unique therapeutic target to assist in the treatment of pain. It is hereby proposed that pharmacogenetic testing of certain candidate genes (i.e., mu receptors, PENK etc.) will result in pharmacogenomic solutions personalized to the individual patient, with potential improvement in clinical outcomes.
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Wellman P. Effects of acute administration of phentermine, alone or in combination with dexfenfluramine, on pain reactivity in the adult rat. Pharmacol Biochem Behav 2008; 90:339-43. [DOI: 10.1016/j.pbb.2008.03.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Revised: 02/19/2008] [Accepted: 03/14/2008] [Indexed: 11/26/2022]
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Reyes S, Mitrofanis J. Patterns of FOS expression in the spinal cord and periaqueductal grey matter of 6OHDA-lesioned rats. Int J Neurosci 2008; 118:1053-79. [PMID: 18576208 DOI: 10.1080/00207450701239210] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
A less well-known feature of Parkinson disease is that up to 40% of patients experience distinct sensory disturbances, including hyperalgesia and chronic pain. There is a limited understanding of the neural mechanisms that generate these symptoms, however. This study explores the patterns of Fos expression (a well-known marker for changes in cell activity) in the spinal cord and periaqueductal grey matter (PaG), two major sensory (nociceptive) centers, of hemiParkinsonian rats. The medial forebrain bundle (mfb; major tract carrying dopaminergic nigrostriatal axons) was injected with either 6OHDA or saline (controls). A week later, some rats were subjected to mechanical stimulation (pinching) of the hindpaw for 2 h, whereas others received no stimulation. Thereafter, brains were processed using routine tyrosine hydroxylase (marker for dopaminergic cells) or Fos immunocytochemistry. In the PaG, there were many more Fos(+) cells in the 6OHDA-lesioned than in the Control group, in both the stimulation and, in particular, the non-stimulation cases. In the spinal cord, there were also more Fos(+) cells in the 6OHDA-lesioned than in the Control group, but in the stimulation cases only. Overall, the results show distinct changes in Fos expression in the spinal cord and PaG of 6OHDA-lesioned rats, suggesting a substrate for some of the abnormal sensory (nociceptive) circuits that may be evident in parkinsonian cases.
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Affiliation(s)
- Stephanie Reyes
- Department Anatomy and Histology, University of Sydney, Sydney, Australia
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Affective analgesia following muscarinic activation of the ventral tegmental area in rats. THE JOURNAL OF PAIN 2008; 9:597-605. [PMID: 18387853 DOI: 10.1016/j.jpain.2008.01.334] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2007] [Revised: 01/25/2008] [Accepted: 01/28/2008] [Indexed: 11/20/2022]
Abstract
UNLABELLED Cholinergic stimulation of dopamine neurons in the ventral tegmental area (VTA) underlies activation of the brain reward circuitry. Activation of this circuit is proposed to preferentially suppress the affective reaction to noxious stimulation. Vocalization afterdischarges (VADs) are a validated model of the affective response of rats to noxious tail shock. The antinociceptive action of the acetylcholine agonist carbachol microinjected into the VTA on VAD threshold was compared with its effect on the thresholds of other tail shock-elicited responses (VDS, vocalizations during shock; SMR, spinal motor reflexes). Whereas VADs are organized within the forebrain, VDSs and SMRs are organized at medullary and spinal levels of the neuraxis, respectively. Carbachol (1 microg, 2 microg, and 4 microg) injected into VTA produced dose-dependent increases in VAD and VDS thresholds, although increases in VAD threshold were significantly greater than increases in VDS threshold. Administration of carbachol into VTA failed to elevate SMR threshold. Elevations in vocalization thresholds produced by intra-VTA carbachol were reversed in a dose-dependent manner by local administration of the muscarinic receptor antagonist atropine sulfate (30 microg and 60 microg). These results provide the first demonstration of the involvement of the VTA in muscarinic-induced suppression of pain affect. PERSPECTIVE Cholinergic activation of the brain reward circuit produced a preferential suppression of rats' affective reaction to noxious stimulation. The neurobiology that relates reinforcement to suppression of pain affect may provide insights into new treatments for pain and its associated affective disorders.
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Kamerman PR, Becker N, Fick LG. Interactions between metoclopramide and morphine: enhanced antinociception and motor dysfunction in rats. Clin Exp Pharmacol Physiol 2007; 34:106-12. [PMID: 17201744 DOI: 10.1111/j.1440-1681.2007.04533.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
1. Opioid analgesics and anti-emetics are often used concomitantly to treat pain and nausea and vomiting in people with malignant disease. We investigated interactions between the opioid analgesic morphine and the anti-emetic metoclopramide, a dopamine D2 receptor antagonist, on nociception and gross motor function. 2. To assess for antinociceptive interactions, 11 Sprague-Dawley rats were injected intraperitoneally with morphine (5.0 mg/kg) or saline in combination with metoclopramide (0.5, 1.5 and 5.0 mg/kg) or saline and, 30 min later, the tail-flick latencies to a noxious thermal stimulus (49 degrees C water) were measured. Immediately thereafter we induced reperfusion hyperalgesia in the rats' tails using a tourniquet cuff and tested nociception again. Because, in addition to its ability to block D2 receptors, metoclopramide is also a weak 5-HT(3) receptor antagonist, we assessed in a further 11 rats whether any antinociceptive interactions occurred between morphine (5.0 mg/kg) and ondansetron (0.2 and 2.0 mg/kg), an anti-emetic that selectively antagonizes 5-HT(3) receptors. To assess for motor interactions, we injected another group of nine rats with morphine (5.0 mg/kg) or saline in combination with metoclopramide (0.5 and 5.0 mg/kg) or saline and tested the ability of the animals to run on an 80 mm diameter rod rotating at 25 r.p.m. for 30 min. 3. Metoclopramide was not inherently analgesic or antihyperalgesic, but the highest dose of metoclopramide (5.0 mg/kg) enhanced the analgesic and antihyperalgesic effects of morphine. Neither dose of ondansetron was analgesic or antihyperalgesic or enhanced the antinociceptive actions of morphine. 4. Only the high dose of metoclopramide compromised running performance when administered with saline. However, coadministering morphine with metoclopramide (both doses) decreased motor performance. 5. Therefore, metoclopramide, possibly through its actions on D2 receptors and not 5-HT(3) receptors, enhances the analgesic and antihyperalgesic effects of morphine, but morphine exacerbates metoclopramide-induced motor dysfunction in rats.
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Affiliation(s)
- Peter R Kamerman
- School of Physiology, University of the Witwatersrand, Johannesburg, South Africa.
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Wood PB, Patterson JC, Sunderland JJ, Tainter KH, Glabus MF, Lilien DL. Reduced presynaptic dopamine activity in fibromyalgia syndrome demonstrated with positron emission tomography: a pilot study. THE JOURNAL OF PAIN 2006; 8:51-8. [PMID: 17023218 DOI: 10.1016/j.jpain.2006.05.014] [Citation(s) in RCA: 162] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2006] [Revised: 05/21/2006] [Accepted: 05/26/2006] [Indexed: 10/24/2022]
Abstract
UNLABELLED Although the pathophysiology underlying the pain of fibromyalgia syndrome (FMS) remains unknown, a variety of clinical and investigational findings suggests a dysregulation of dopaminergic neurotransmission. We therefore investigated presynaptic dopaminergic function in 6 female FMS patients in comparison to 8 age- and gender-matched controls as assessed by positron emission tomography with 6-[(18)F]fluoro-L-DOPA as a tracer. Semiquantitative analysis revealed reductions in 6-[(18)F]fluoro-L-DOPA uptake in several brain regions, indicating a disruption of presynaptic dopamine activity wherein dopamine plays a putative role in natural analgesia. Although the small sample size makes these findings preliminary, it appears that FMS might be characterized by a disruption of dopaminergic neurotransmission. PERSPECTIVE An association between FMS and reduced dopamine metabolism within the pain neuromatrix provides important insights into the pathophysiology of this mysterious disorder.
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Affiliation(s)
- Patrick B Wood
- Department of Family Medicine and Anesthesiology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA 71103, USA.
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Wood PB. Mesolimbic dopaminergic mechanisms and pain control. Pain 2006; 120:230-234. [PMID: 16427195 DOI: 10.1016/j.pain.2005.12.014] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2005] [Accepted: 12/09/2005] [Indexed: 10/25/2022]
Affiliation(s)
- Patrick B Wood
- Departments of Family Medicine, Anesthesiology and Psychiatry, Louisiana State University Health Sciences Center, Shreveport, USA
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Takeda R, Ikeda T, Tsuda F, Abe H, Hashiguchi H, Ishida Y, Nishimori T. Unilateral lesions of mesostriatal dopaminergic pathway alters the withdrawal response of the rat hindpaw to mechanical stimulation. Neurosci Res 2005; 52:31-6. [PMID: 15811550 DOI: 10.1016/j.neures.2005.01.005] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2004] [Revised: 12/23/2004] [Accepted: 01/13/2005] [Indexed: 10/25/2022]
Abstract
To investigate the role mesostriatal dopamine system plays in pain processing, we examined the withdrawal response of rat hindpaws to mechanical stimulus at 1, 4, and 12 weeks after unilateral 6-hydroxydopamine (6-OHDA) lesions of the mesostriatal pathway. In all of the 6-OHDA rats examined, almost no tyrosine hydroxylase (TH) immunoreactivity was detected in the substantia nigra, ventral tegmental area, and striatum ipsilateral to 6-OHDA lesions. Alteration in the withdrawal response in this model animal was evaluated by comparing the latency of withdrawal reflex following the mechanical stimulus to the hindpaw. The latency of withdrawal response in the 6-OHDA rats was significantly reduced in the side ipsilateral to 6-OHDA lesions at all times observed, whereas that was not changed through the period observed in the contralateral side, indicating that dopamine depletion in the mesostriatal system has the influence on withdrawal response to the mechanical stimulus. These results show that the unilateral dopamine depletion causes hypersensitivity to the mechanical stimulus in the ipsilateral side, suggesting that, at least in part, dopamine in the mesostriatal system may be involved in sensory processing including pain sensation induced by mechanical stimulation.
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Affiliation(s)
- Ryuichiro Takeda
- Department of Psychiatry, Miyazaki Medical College, University of Miyazaki, Miyazaki 889-1692, Japan
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Fang LH, Zhang YH, Ku BS. Fangchinoline inhibited the antinociceptive effect of morphine in mice. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2005; 12:183-188. [PMID: 15830839 DOI: 10.1016/j.phymed.2003.06.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Fangchinoline (FAN), a non-specific calcium antagonist, is a major alkaloidal component of the creeper Stephania tetrandra S. Moore (or fenfangji). It has been shown to possess antagonistic activity on morphine-induced antinociception in mice. This study was undertaken to assess the antagonistic mechanism. The results demonstrated that FAN (IP) attenuated morphine (SC)-induced antinociception in a dose-dependent manner with significant effect at doses of 30 and 60mg/kg body wt. (IP) in the tail-flick test but not the tail-pinch tests, carried out in mice. This antagonism was abolished by pretreatment with a serotonin precursor, 5-hydroxytryptophan (5-HTP, IP), but not by pretreatment with a noradrenaline precursor, L-dihydroxyphenylalanine (L-DOPA, IP) in the tail-flick test. On the other hand, the development of morphine-induced analgesic tolerance was not prevented by FAN. These results suggest that the serotonergic pathway may be involved in the antagonism of morphine-induced antinociception by FAN and, in agreement with other reports, also indicates the possible dissociation of the morphine analgesic effect from its tolerance-development mechanism.
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Affiliation(s)
- L H Fang
- National Center for Pharmaceutical Screening, Institute of Materia Medica, Chinese Academy of Medical Sciences, Beijing 100050, China
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Abstract
Repeated administrations of addictive drugs produce long-lasting changes in brain and behavior. However, drug-induced neurobehavioral plasticity is not a mere function of the neuropharmacological actions of drugs, but the result of complex drug-environment interactions. In the present review we summarize results obtained in a series of studies using an animal model of drug-environment interaction, showing that environmental context and past drug history interact to modulate the effects of amphetamine, cocaine and morphine on behavior, gene expression and structural plasticity. These findings may help shed some light on the conditions necessary for addictive drugs to enduringly alter brain and behavior.
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Affiliation(s)
- A Badiani
- Department of Human Physiology and Pharmacology Vittorio Erspamer, University of Rome La Sapienza, Roma, Italy.
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Hagelberg N, Aalto S, Kajander J, Oikonen V, Hinkka S, Någren K, Hietala J, Scheinin H. Alfentanil increases cortical dopamine D2/D3 receptor binding in healthy subjects. Pain 2004; 109:86-93. [PMID: 15082129 DOI: 10.1016/j.pain.2004.01.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2003] [Revised: 12/16/2003] [Accepted: 01/12/2004] [Indexed: 10/26/2022]
Abstract
Animal studies have shown that opioids modulate the function of dopaminergic neurons. The effect of alfentanil on cortical and thalamic binding of the D2/D3 receptor ligand [(11)C]FLB 457 was evaluated in eight healthy subjects with positron emission tomography. The simplified reference tissue model was used to calculate tracer binding potential (BP) during a baseline condition and target-controlled infusion of alfentanil, and the results were analyzed using a comparison group not receiving opioid. Behavioral and analgesic effects of alfentanil were also evaluated. In the region-of-interest analysis, alfentanil increased the BP of [(11)C]FLB 457 in the medial frontal cortex (P=0.0027), dorsolateral prefrontal cortex (P=0.027) superior temporal cortex (P=0.028), and medial thalamus (P=0.003) These results were confirmed in a voxel-based analysis, which further revealed an opioid-induced increase in [(11)C]FLB 457 BP in the anterior cingulate cortex (P<0.001). Alfentanil induced euphoria (P=0.003) and analgesia (P=0.006) Cheerfulness (r=0.918, P=0.001) and euphoria (r=0.982, P<0.001) were associated with increased BP of [(11)C]FLB 457 in the left posterior cingulate cortex, but the analgesic effect of alfentanil did not correlate with changes in [(11)C]FLB 457 BP. The results of this study demonstrate opioid-dopamine interactions in frontal and temporal cortical regions and the thalamus in healthy subjects. Increased D2/D3 tracer binding during opioid infusion may reflect decreased synaptic dopamine levels. The association of the uplifting effect of alfentanil with increased D2/D3 binding in the posterior cingulate cortex suggests that cortical dopamine may be involved in the behavioral effects of opioids.
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Affiliation(s)
- Nora Hagelberg
- Turku PET Centre, University of Turku, P.O. Box 52, FIN 20521 Turku, Finland.
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48
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Ozaki S, Narita M, Narita M, Ozaki M, Khotib J, Suzuki T. Role of extracellular signal-regulated kinase in the ventral tegmental area in the suppression of the morphine-induced rewarding effect in mice with sciatic nerve ligation. J Neurochem 2004; 88:1389-97. [PMID: 15009639 DOI: 10.1046/j.1471-4159.2003.02272.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We recently reported that micro-opioid receptor agonist morphine failed to induce its rewarding effects in rodents with sciatic nerve injury. In the present study, we investigated whether a state of neuropathic pain induced by sciatic nerve ligation could change the activities of the extracellular signal-regulated kinase (ERK) and p38 in the mouse lower midbrain area including the ventral tegmental area (VTA), and these changes could directly affect the development of the morphine-induced rewarding effect in mice. The sciatic nerve ligation caused a long-lasting and profound thermal hyperalgesia. A dose-dependent place preference induced by s.c. administration of morphine was observed in sham-operated mice, but not in sciatic nerve-ligated mice. We found here for the first time that nerve injury produces a sustained and significant reduction in protein levels of phosphorylated-ERK and -p38 in cytosolic preparations of the mouse lower midbrain. The inhibition of ERK activity by i.c.v. pre-treatment with either PD98059 or U0126 impaired the morphine-induced place preference. In contrast, i.c.v. treatment with a specific inhibitor of p38, SB203580, did not interfere with the morphine-induced rewarding effect. Immunohistochemical study showed a drastic reduction in phosphorylated-ERK immunoreactivity within tyrosine hydroxylase-positive cells of the VTA. These results suggest that a sustained reduction in the ERK-dependent signalling pathway in dopamine cells of the VTA may be implicated in the suppression of the morphine-induced rewarding effect under neuropathic pain.
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Affiliation(s)
- Satoru Ozaki
- Department of Toxicology, Hoshi University School of Pharmacy and Pharmaceutical Sciences, Shinagawa-ku, Tokyo, Japan
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49
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Narita M, Suzuki M, Imai S, Narita M, Ozaki S, Kishimoto Y, Oe K, Yajima Y, Yamazaki M, Suzuki T. Molecular mechanism of changes in the morphine-induced pharmacological actions under chronic pain-like state: Suppression of dopaminergic transmission in the brain. Life Sci 2004; 74:2655-73. [PMID: 15041447 DOI: 10.1016/j.lfs.2004.01.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
In the present study, we demonstrated whether a neuropathic pain-like state induced by sciatic nerve ligation in rodents could cause a long-lasting change in intracellular signaling in both supraspinal and spinal cord related to the suppression of morphine's effect. Mice with sciatic nerve ligation exhibited a significant suppression of the morphine-induced antinociception. Under this condition, phosphorylated-conventional protein kinase C-like immunoreactivity (p-cPKC-IR) and phosphorylated-micro-opioid receptor (p-MOR)-IR were clearly increased on the ipsilateral side in the dorsal horn of the spinal cord of nerve-ligated mice. It is of interest to note that astroglial hypertrophy as well as its proliferation was also noted in this area of sciatic nerve-ligated mice. Like nerve injury, the increase in cPKC activities and astroglial hypertrophy/proliferation in this region was observed by repeated morphine treatment. These findings suggest that the phosphorylation of both cPKC and MOR in the dorsal horn of the spinal cord by sciatic nerve ligation may play a substantial role in the suppression of morphine-induced antinociception under a neuropathic pain-like state. Sciatic nerve injury also caused a significant inhibition of MOR-mediated G-protein activation onto GABAergic neurons and a dramatic reduction in ERK activities onto dopaminergic neurons in the ventral tegmental area (VTA) regulating the rewarding effect of opioids. Furthermore, we found that the inhibition of ERK cascade in the VTA by treatment with specific inhibitors suppressed the morphine-induced rewarding effect in normal mice. These findings provide evidence that the direct reduction in MOR function and the persistent decrease in ERK activity of dopaminergic neurons in the VTA may contribute to the suppression of the morphine-induced rewarding effect under a neuropathic pain-like state. Conclusively, our recent findings provide novel evidences for the mechanism underlying the less sensitivity to opioids under a neuropathic pain-like state.
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Affiliation(s)
- Minoru Narita
- Department of Toxicology, Hoshi University School of Pharmacy and Pharmaceutical Sciences, 2-4-41 Ebara, Shinagawa-ku, Tokyo, 142-8501, Japan.
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50
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Kirouac GJ, Li S, Mabrouk G. GABAergic projection from the ventral tegmental area and substantia nigra to the periaqueductal gray region and the dorsal raphe nucleus. J Comp Neurol 2004; 469:170-84. [PMID: 14694532 DOI: 10.1002/cne.11005] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Previous studies have shown that neurons in the ventral tegmental area (VTA) and substantia nigra (SN) project to the ventrolateral periaqueductal gray (PAGvl) and dorsal raphe nucleus (DR). Research has also shown that stimulation of neurons in the VTA/SN elicits cardiovascular depressor responses that are mediated by a projection to the PAGvl/DR. Anatomic and physiological experiments were done in the present study to determine the neurochemical identity of the VTA/SN projection to the PAGvl/DR. Experiments were done to characterize the origin and chemical nature of this projection by combining cholera toxin B tracing with immunofluorescence for the 67K isoform of glutamic acid decarboxylase (GAD) and tyrosine hydroxylase. The PAGvl/DR region was found to receive a substantial input from neurons in the VTA, SN, and deep mesencephalic nucleus. The DR was preferentially innervated by neurons in the VTA, whereas the PAGvl was preferentially innervated by neurons in the SN. A proportion of neurons in the VTA and the reticular portion of the SN found to project to the PAGvl/DR were GAD positive. In addition, experiments were done in urethane-anesthetized rats to determine whether injections of a gamma-aminobutyric acid (GABA) antagonist in the region of the PAGvl/DR attenuated the cardiovascular depressor responses produced by glutamate stimulation of the VTA/SN. Injections of the GABA-blocking agent picrotoxin (2.5 nmol, 500 nl) into the PAGvl/DR eliminated the cardiovascular responses from stimulation of the VTA/SN (0.01 M, 50 nl). The results of the present investigation provide evidence for a GABAergic projection from the VTA/SN to the PAGvl/DR. This projection may be an important regulator of the PAGvl/DR, an area of the midbrain involved in the production of behavioral and physiological responses to pain and stress.
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Affiliation(s)
- Gilbert J Kirouac
- Division of Basic Medical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, A1B 3V6, Canada
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