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Raman S, Ikutame D, Okura K, Matsuka Y. Targeted Therapy for Orofacial Pain: A Novel Perspective for Precision Medicine. J Pers Med 2023; 13:jpm13030565. [PMID: 36983746 PMCID: PMC10057163 DOI: 10.3390/jpm13030565] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/16/2023] [Accepted: 03/20/2023] [Indexed: 03/30/2023] Open
Abstract
Orofacial pain (OFP) is a dental specialty that includes the diagnosis, management and treatment of disorders of the jaw, mouth, face, head and neck. Evidence-based understanding is critical in effectively treating OFPs as the pathophysiology of these conditions is multifactorial. Since OFP impacts the quality of life of the affected individuals, treating patients successfully is of the utmost significance. Despite the therapeutic choices available, treating OFP is still quite challenging, owing to inter-patient variations. The emerging trends in precision medicine could probably lead us to a paradigm shift in effectively managing the untreatable long-standing pain conditions. Precision medicine is designed based on the patient's genetic profile to meet their needs. Several significant relationships have been discovered based on the genetics and genomics of pain in the past, and some of the notable targets are discussed in this review. The scope of this review is to discuss preclinical and clinical trials that include approaches used in targeted therapy for orofacial pain. Future developments in pain medicine should benefit from current trends in research into novel therapeutic approaches.
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Affiliation(s)
- Swarnalakshmi Raman
- Department of Stomatognathic Function and Occlusal Reconstruction, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan
| | - Daisuke Ikutame
- Department of Stomatognathic Function and Occlusal Reconstruction, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan
| | - Kazuo Okura
- Department of Stomatognathic Function and Occlusal Reconstruction, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan
| | - Yoshizo Matsuka
- Department of Stomatognathic Function and Occlusal Reconstruction, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan
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2
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Stefanucci A, Minosi P, Pieretti S, Tanguturi P, Molnar G, Scioli G, Marinaccio L, Della Valle A, Streicher JM, Mollica A. Design of Analgesic Trivalent Peptides with Low Withdrawal Symptoms: Probing the Antinociceptive Profile of Novel Linear and Cyclic Peptides as Opioid Pan Ligands. ACS Chem Neurosci 2023; 14:506-515. [PMID: 36651179 DOI: 10.1021/acschemneuro.3c00005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The discovery of efficacious and safe analgesics with reduced side effects is the foremost challenge in the pain field. In this work, we report the in vitro and in vivo evaluation of linear and cyclic analogues of biphalin with the aim to complete the series of structural modifications previously applied in the development of opioid peptides incorporating a xylene bridge. Replacement of Tyr1,1' by Dmt (2,5-dimethyltyrosine) in the linear biphalin analogue AM94 and cyclic analogue MACE4 resulted in two new compounds (namely, MJ2 and MJ5) endowed with improved KOR/MOR/DOR binding affinity. Both compounds showed a strong antinociceptive profile in in vivo models of nociception, allodynia, and hyperalgesia via the tail flick, hot plate, and formalin tests after intracerebroventricular and subcutaneous administration. One of these ligands, MJ2, was also tested in tolerance and dependence studies, exhibiting very little withdrawal symptoms.
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Affiliation(s)
- Azzurra Stefanucci
- Dipartimento di Farmacia, Universitá; di Chieti-Pescara "G. d'Annunzio", Via dei Vestini 31, 66100 Chieti, Italy
| | - Paola Minosi
- Centro Nazionale Ricerca e Valutazione Preclinica e Clinica dei Farmaci, Istituto Superiore di Sanita, Viale Regina Elena 299, 00161 Rome, Italy
| | - Stefano Pieretti
- Centro Nazionale Ricerca e Valutazione Preclinica e Clinica dei Farmaci, Istituto Superiore di Sanita, Viale Regina Elena 299, 00161 Rome, Italy
| | | | - Gabriella Molnar
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, Arizona 85012, United States
| | - Giuseppe Scioli
- Dipartimento di Farmacia, Universitá; di Chieti-Pescara "G. d'Annunzio", Via dei Vestini 31, 66100 Chieti, Italy
| | - Lorenza Marinaccio
- Dipartimento di Farmacia, Universitá; di Chieti-Pescara "G. d'Annunzio", Via dei Vestini 31, 66100 Chieti, Italy
| | - Alice Della Valle
- Dipartimento di Farmacia, Universitá; di Chieti-Pescara "G. d'Annunzio", Via dei Vestini 31, 66100 Chieti, Italy
| | - John M Streicher
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, Arizona 85012, United States.,Comprehensive Pain and Addiction Center, University of Arizona, Tucson, Arizona 85012, United States
| | - Adriano Mollica
- Dipartimento di Farmacia, Universitá; di Chieti-Pescara "G. d'Annunzio", Via dei Vestini 31, 66100 Chieti, Italy
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3
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Meerschaert KA, Edwards BS, Epouhe AY, Jefferson B, Friedman R, Babyok OL, Moy JK, Kehinde F, Liu C, Workman CJ, Vignali DAA, Albers KM, Koerber HR, Gold MS, Davis BM, Scheff NN, Saloman JL. Neuronally expressed PDL1, not PD1, suppresses acute nociception. Brain Behav Immun 2022; 106:233-246. [PMID: 36089217 PMCID: PMC10343937 DOI: 10.1016/j.bbi.2022.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 08/21/2022] [Accepted: 09/03/2022] [Indexed: 11/20/2022] Open
Abstract
PDL1 is a protein that induces immunosuppression by binding to PD1 expressed on immune cells. In line with historical studies, we found that membrane-bound PD1 expression was largely restricted to immune cells; PD1 was not detectable at either the mRNA or protein level in peripheral neurons using single neuron qPCR, immunolabeling and flow cytometry. However, we observed widespread expression of PDL1 in both sensory and sympathetic neurons that could have important implications for patients receiving immunotherapies targeting this pathway that include unexpected autonomic and sensory related effects. While signaling pathways downstream of PD1 are well established, little to no information is available regarding the intracellular signaling downstream of membrane-bound PDL1 (also known as reverse signaling). Here, we administered soluble PD1 to engage neuronally expressed PDL1 and found that PD1 significantly reduced nocifensive behaviors evoked by algogenic capsaicin. We used calcium imaging to examine the underlying neural mechanism of this reduction and found that exogenous PD1 diminished TRPV1-dependent calcium transients in dissociated sensory neurons. Furthermore, we observed a reduction in membrane expression of TRPV1 following administration of PD1. Exogenous PD1 had no effect on pain-related behaviors in sensory neuron specific PDL1 knockout mice. These data indicate that neuronal PDL1 activation is sufficient to modulate sensitivity to noxious stimuli and as such, may be an important homeostatic mechanism for regulating acute nociception.
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Affiliation(s)
- Kimberly A Meerschaert
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Brian S Edwards
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Ariel Y Epouhe
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Bahiyyah Jefferson
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Robert Friedman
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Olivia L Babyok
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Jamie K Moy
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Faith Kehinde
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Chang Liu
- Department of Immunology, University of Pittsburgh School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States; Tumor Microenvironment Center, UPMC Hillman Cancer Center, Pittsburgh, PA, United States
| | - Creg J Workman
- Department of Immunology, University of Pittsburgh School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States; Tumor Microenvironment Center, UPMC Hillman Cancer Center, Pittsburgh, PA, United States
| | - Dario A A Vignali
- Department of Immunology, University of Pittsburgh School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States; Tumor Microenvironment Center, UPMC Hillman Cancer Center, Pittsburgh, PA, United States; Cancer Immunology and Immunotherapy Program, UPMC Hillman Cancer Center, Pittsburgh, PA, United States
| | - Kathryn M Albers
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - H Richard Koerber
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Michael S Gold
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Brian M Davis
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Nicole N Scheff
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Biobehavioral Cancer Control Program, UPMC Hillman Cancer Center, Pittsburgh, PA, United States
| | - Jami L Saloman
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Center for Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Biobehavioral Cancer Control Program, UPMC Hillman Cancer Center, Pittsburgh, PA, United States; Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.
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4
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Short SAP, Wilkinson K, Long DL, Judd S, Schulte J, Kissela BM, Howard G, Cushman M. Plasma Pro-Enkephalin A and Ischemic Stroke Risk: The Reasons for Geographic and Racial Differences in Stroke Cohort. J Stroke Cerebrovasc Dis 2022; 31:106237. [PMID: 34896817 PMCID: PMC8792292 DOI: 10.1016/j.jstrokecerebrovasdis.2021.106237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 11/05/2021] [Accepted: 11/20/2021] [Indexed: 02/03/2023] Open
Abstract
OBJECTIVES The opioid neuropeptide pro-enkephalin A (PENK-A) may be a circulating marker of cardiovascular risk, with prior findings relevant to heart failure, kidney disease, and vascular dementia. Despite these findings, the association of PENK-A with ischemic stroke is unknown, so we examined this association in a prospective cohort study and analyzed differences by race and sex. MATERIALS AND METHODS The REasons for Geographic and Racial Differences in Stroke study (REGARDS) is a prospective cohort study of 30,239 Black and White adults. Plasma PENK-A was measured in 473 participants that developed first-time ischemic stroke over 5.9 years and 899 randomly selected participants. Cox models adjusted for demographics and stroke risk factors were used to calculate hazard ratios (HRs) of stroke by baseline PENK-A. RESULTS PENK-A was higher with increasing age, female sex, White race, lower body mass index, and antihypertensive medication use. Each SD higher increment of PENK-A was associated with an adjusted HR of 1.20 (95% CI 1.01-1.42) for stroke, with minimal confounding by stroke risk factors. Spline plots suggested a U-shaped relationship, particularly in White men, with an adjusted HR 3.88 (95% CI 1.94-7.77) for the 95th versus 50th percentile of PENK-A in White men. CONCLUSIONS Higher baseline plasma PENK-A was independently associated with future stroke risk in REGARDS. This association was most apparent among White men. There was little confounding by established stroke risk factors, suggesting a possible causal role in stroke etiology. Further research is needed to understand the role of endogenous opioids in stroke pathogenesis.
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Affiliation(s)
- Samuel AP Short
- Larner College of Medicine, University of Vermont, Burlington, VT
| | - Katherine Wilkinson
- Department of Pathology and Laboratory Medicine, Larner College of Medicine, University of Vermont, Burlington, VT
| | - D Leann Long
- Department of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, AL
| | - Suzanne Judd
- Department of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, AL
| | | | - Brett M Kissela
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati College of Medicine, Cincinnati, OH
| | - George Howard
- Department of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, AL
| | - Mary Cushman
- Department of Pathology and Laboratory Medicine, Larner College of Medicine, University of Vermont, Burlington, VT,Department of Medicine, Larner College of Medicine, University of Vermont, Burlington, VT,Address for Correspondence: Mary Cushman, MD MSc, University of Vermont, 360 South Park Drive, Colchester, VT 05446,
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5
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Liu Q, He H, Mai L, Yang S, Fan W, Huang F. Peripherally Acting Opioids in Orofacial Pain. Front Neurosci 2021; 15:665445. [PMID: 34017236 PMCID: PMC8129166 DOI: 10.3389/fnins.2021.665445] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 04/12/2021] [Indexed: 12/12/2022] Open
Abstract
The activation of opioid receptors by exogenous or endogenous opioids can produce significant analgesic effects in peripheral tissues. Numerous researchers have demonstrated the expression of peripheral opioid receptors (PORs) and endogenous opioid peptides (EOPs) in the orofacial region. Growing evidence has shown the involvement of PORs and immune cell-derived EOPs in the modulation of orofacial pain. In this review, we discuss the role of PORs and EOPs in orofacial pain and the possible cellular mechanisms involved. Furthermore, the potential development of therapeutic strategies for orofacial pain is also summarized.
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Affiliation(s)
- Qing Liu
- Department of Pediatric Dentistry, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China
| | - Hongwen He
- Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China.,Department of Oral Anatomy and Physiology, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Lijia Mai
- Department of Pediatric Dentistry, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China
| | - Shengyan Yang
- Department of Pediatric Dentistry, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China
| | - Wenguo Fan
- Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China
| | - Fang Huang
- Department of Pediatric Dentistry, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China
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6
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Gonçalves WA, Ferreira RCM, Rezende BM, Mahecha GAB, Gualdron M, de Macedo FHP, Duarte IDG, Perez AC, Machado FS, Cruz JS, Romero TRL. Endogenous opioid and cannabinoid systems modulate the muscle pain: A pharmacological study into the peripheral site. Eur J Pharmacol 2021; 901:174089. [PMID: 33826922 DOI: 10.1016/j.ejphar.2021.174089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 03/29/2021] [Accepted: 03/31/2021] [Indexed: 11/16/2022]
Abstract
The participation of the peripheral opioid and cannabinoid endogenous systems in modulating muscle pain and inflammation has not been fully explored. Thus, the aim of this study was to investigate the involvement of these endogenous systems during muscular-tissue hyperalgesia induced by inflammation. Hyperalgesia was induced by carrageenan injection into the tibialis anterior muscles of male Wistar rats. We padronized an available Randal-Sellito test adaptation to evaluate nociceptive behavior elicited by mechanical insult in muscles. Western blot analysis was performed to evaluate the expression levels of opioid and cannabinoid receptors in the dorsal root ganglia. The non-selective opioid peptide receptor antagonist (naloxone) and the selective mu opioid receptor MOP (clocinnamox) and kappa opioid receptor KOP (nor-binaltorphimine) antagonists were able to intensify carrageenan-induced muscular hyperalgesia. On the other hand, the selective delta opioid receptor (DOP) antagonist (naltrindole) did not present any effect on nociceptive behavior. Moreover, the selective inhibitor of aminopeptidases (Bestatin) provoked considerable dose-dependent analgesia when intramuscularly injected into the hyperalgesic muscle. The CB1 receptor antagonist (AM251), but not the CB2 receptor antagonist (AM630), intensified muscle hyperalgesia. All irreversible inhibitors of anandamide hydrolase (MAFP), the inhibitor for monoacylglycerol lipase (JZL184) and the anandamide reuptake inhibitor (VDM11) decreased carrageenan-induced hyperalgesia in muscular tissue. Lastly, MOP, KOP and CB1 expression levels in DRG were baseline even after muscular injection with carrageenan. The endogenous opioid and cannabinoid systems participate in peripheral muscle pain control through the activation of MOP, KOP and CB1 receptors.
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Affiliation(s)
- William A Gonçalves
- Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, Brazil
| | - Renata C M Ferreira
- Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, Brazil
| | - Barbara M Rezende
- Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Brazil
| | - German A B Mahecha
- Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Brazil
| | - Melissa Gualdron
- Department of Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas Gerais, Brazil
| | - Flávio H P de Macedo
- Department of Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas Gerais, Brazil
| | - Igor D G Duarte
- Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, Brazil
| | - Andrea C Perez
- Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, Brazil
| | - Fabiana S Machado
- Department of Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas Gerais, Brazil
| | - Jader S Cruz
- Department of Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas Gerais, Brazil
| | - Thiago R L Romero
- Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, Brazil.
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7
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Olson EM, Akintola T, Phillipsc J, Blasini M, Haycock NR, Martinez PE, Greenspan JD, Dorsey SG, Wang Y, Colloca L. Effects of sex on placebo effects in chronic pain participants: a cross-sectional study. Pain 2021; 162:531-542. [PMID: 32826757 PMCID: PMC7854995 DOI: 10.1097/j.pain.0000000000002038] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 08/03/2020] [Indexed: 12/19/2022]
Abstract
ABSTRACT Sex-related differences can influence outcomes of randomized clinical trials and may jeopardize the effectiveness of pain management and other therapeutics. Thus, it is essential to understand the mechanistic and translational aspects of sex differences in placebo outcomes. Recently, studies in healthy participants have shed light on how sex-related placebo effects might influence outcomes, yet no research has been conducted in a patient population. Herein, we used a tripartite approach to evaluate the interaction of prior therapeutic experience (eg, conditioning), expectations, and placebo effects in 280 chronic (orofacial) pain patients (215 women). In this cross-sectional study, we assessed sex differences in placebo effects, conditioning as a proxy of prior therapeutic effects, and expectations evaluated before and after the exposure to positive outcomes, taking into account participant-experimenter sex concordance and hormonal levels (estradiol and progesterone assessed in premenopausal women). We used mediation analysis to determine how conditioning strength and expectations impacted sex differences in placebo outcomes. Independent of gonadal hormone levels, women showed stronger placebo effects than men. We also found significant statistical sex differences in the conditioning strength and reinforced expectations whereby reinforced expectations mediated the sex-related placebo effects. In addition, the participant-experimenter sex concordance influenced conditioning strength, reinforced expectations, and placebo effects in women but not in men. Our findings suggest that women experience larger conditioning effects, expectations, and placebo effects emphasizing the need to consider sex as a biological variable when placebo components of any outcomes are part of drug development trials and in pain management.
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Affiliation(s)
| | - Titilola Akintola
- Department of Pain and Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, MD, USA
| | - Jane Phillipsc
- Department of Neural and Pain Sciences, and Brotman Facial Pain Clinic, School of Dentistry, University of Maryland, Baltimore, MD, USA
| | - Maxie Blasini
- Department of Pain and Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, MD, USA
| | - Nathaniel R. Haycock
- Department of Pain and Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, MD, USA
| | - Pedro E. Martinez
- National Institutes of Health, National Institute of Mental Health, Bethesda, MD, USA
| | - Joel D. Greenspan
- Department of Neural and Pain Sciences, and Brotman Facial Pain Clinic, School of Dentistry, University of Maryland, Baltimore, MD, USA
- University of Maryland Center to Advance Chronic Pain Research, Baltimore, MD, USA
| | - Susan G. Dorsey
- Department of Pain and Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, MD, USA
- University of Maryland Center to Advance Chronic Pain Research, Baltimore, MD, USA
| | - Yang Wang
- Department of Pain and Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, MD, USA
| | - Luana Colloca
- Department of Pain and Translational Symptom Science, School of Nursing, University of Maryland, Baltimore, MD, USA
- University of Maryland Center to Advance Chronic Pain Research, Baltimore, MD, USA
- Department of Anesthesiology, School of Medicine, University of Maryland, Baltimore, MD, USA
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8
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Ortiz MI, Cariño-Cortés R, Castañeda-Hernández G. Participation of the opioid receptor - nitric oxide - cGMP - K + channel pathway in the peripheral antinociceptive effect of nalbuphine and buprenorphine in rats. Can J Physiol Pharmacol 2020; 98:753-762. [PMID: 33095677 DOI: 10.1139/cjpp-2020-0104] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The aim of this study was to examine if the peripheral antinociceptive effects of the opioid agonist/antagonist nalbuphine and buprenorphine involve the sequential participation of nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) synthesis followed by K+ channel opening in the formalin test. Wistar rats (180-220 g) were injected in the dorsal surface of the right hind paw with formalin (1%). Rats received a subcutaneous (s.c.) injection into the dorsal surface of the paw of vehicles or increasing doses of nalbuphine (50-200 μg/paw) or buprenorphine (1-5 μg/paw) 20 min before formalin injection into the paw. Nalbuphine antinociception was reversed by the s.c. injection into the paw of the inhibitor of NO synthesis (NG-nitro-l-arginine methyl ester (L-NAME)), by the inhibitor of guanylyl cyclase (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ)), by the Kir6.1-2, ATP-sensitive K+ channel inhibitors (glibenclamide and glipizide), by the KCa2.1-3, small conductance Ca2+-activated K+ channel blocker (apamin), by the KCa1.1, large conductance Ca2+-activated K+ channel blocker (charybdotoxin), and by the KV, voltage-dependent K+ channel inhibitors (4-aminopyridine (4-AP) and tetraethylammonium chloride (TEA)). The antinociceptive effect produced by buprenorphine was blocked by the s.c. injection of 4-AP and TEA but not by L-NAME, ODQ, glibenclamide, glipizide, apamin, or charybdotoxin. The present results provide evidence for differences in peripheral mechanisms of action between these opioid drugs.
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Affiliation(s)
- Mario I Ortiz
- Área Académica de Medicina del Instituto de Ciencias de la Salud, Universidad Autónoma del Estado de Hidalgo, Pachuca, Hidalgo, Mexico
| | - Raquel Cariño-Cortés
- Área Académica de Medicina del Instituto de Ciencias de la Salud, Universidad Autónoma del Estado de Hidalgo, Pachuca, Hidalgo, Mexico
| | - Gilberto Castañeda-Hernández
- Departamento de Farmacología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de México, Mexico
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9
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Liu Q, Fan W, He H, Huang F. The role of peripheral opioid receptors in orofacial pain. Oral Dis 2020; 27:1106-1114. [PMID: 32437594 DOI: 10.1111/odi.13435] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 05/04/2020] [Accepted: 05/12/2020] [Indexed: 12/20/2022]
Abstract
Opioid receptors are widely distributed in the central and peripheral nervous systems and non-neuronal tissues. Numerous researchers have noted the pivotal role of peripheral opioid receptors (PORs) in analgesia. Accumulating evidence has shown the existence of PORs in the trigeminal nerve system, indicating that PORs may be involved in the modulation of orofacial pain. In this review, we summarise the recent evidence for the role of PORs in orofacial pain and discuss the possible cellular mechanisms.
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Affiliation(s)
- Qing Liu
- Department of Pediatric Dentistry, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China
| | - Wenguo Fan
- Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China
| | - Hongwen He
- Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China.,Department of Oral Anatomy and Physiology, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Fang Huang
- Department of Pediatric Dentistry, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China
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10
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Berthiaume S, Abdallah K, Blais V, Gendron L. Alleviating pain with delta opioid receptor agonists: evidence from experimental models. J Neural Transm (Vienna) 2020; 127:661-672. [PMID: 32189076 DOI: 10.1007/s00702-020-02172-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 03/06/2020] [Indexed: 12/11/2022]
Abstract
The use of opioids for the relief of pain and headache disorders has been studied for years. Nowadays, particularly because of its ability to produce analgesia in various pain models, delta opioid receptor (DOPr) emerges as a promising target for the development of new pain therapies. Indeed, their potential to avoid the unwanted effects commonly observed with clinically used opioids acting at the mu opioid receptor (MOPr) suggests that DOPr agonists could be a therapeutic option. In this review, we discuss the use of opioids in the management of pain in addition to describing the evidence of the analgesic potency of DOPr agonists in animal models.
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Affiliation(s)
- Sophie Berthiaume
- Département de Pharmacologie-Physiologie, Institut de Pharmacologie de Sherbrooke, Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, 3001, 12th Avenue North, Sherbrooke, QC, J1H 5N4, Canada
| | - Khaled Abdallah
- Département de Pharmacologie-Physiologie, Institut de Pharmacologie de Sherbrooke, Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, 3001, 12th Avenue North, Sherbrooke, QC, J1H 5N4, Canada
| | - Véronique Blais
- Département de Pharmacologie-Physiologie, Institut de Pharmacologie de Sherbrooke, Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, 3001, 12th Avenue North, Sherbrooke, QC, J1H 5N4, Canada
| | - Louis Gendron
- Département de Pharmacologie-Physiologie, Institut de Pharmacologie de Sherbrooke, Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, 3001, 12th Avenue North, Sherbrooke, QC, J1H 5N4, Canada.
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11
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Polo S, Díaz AF, Gallardo N, Leánez S, Balboni G, Pol O. Treatment With the Delta Opioid Agonist UFP-512 Alleviates Chronic Inflammatory and Neuropathic Pain: Mechanisms Implicated. Front Pharmacol 2019; 10:283. [PMID: 30971925 PMCID: PMC6443715 DOI: 10.3389/fphar.2019.00283] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 03/07/2019] [Indexed: 12/22/2022] Open
Abstract
We investigated whether administration of the δ-opioid receptor (DOR) agonist H-Dmt-Tic-NH-CH(CH2-COOH)-Bid (UFP-512), which also activates nuclear factor erythroid 2-related factor 2 (Nrf2), alleviated chronic inflammatory and/or neuropathic pain and inhibited the depressive-like behaviors associated with persistent neuropathic pain. The possible mechanisms implicated were also assessed. We evaluated the following effects in male C57BL/6J mice with inflammatory pain induced by complete Freund's adjuvant or neuropathic pain caused by the chronic constriction of sciatic nerve: (1) the antinociceptive effects of UFP-512; (2) the effects of UFP-512 on the expression of Nrf2, heme oxygenase 1 (HO-1), NAD(P)H quinone oxidoreductase 1, phosphoinositide 3-kinase (PI3K), protein kinase B (Akt), inducible nitric oxide synthase, DOR, and mitogen-activated protein kinases (MAPK) in the spinal cord of animals with inflammatory or neuropathic pain; (3) the antinociceptive effects of the coadministration of UFP-512 with the Nrf2 activator sulforaphane (SFN); and (4) the antidepressant effects of UFP-512 in animals with depressive-like behaviors associated with neuropathic pain. Our results demonstrated that the intraperitoneal administration of UFP-512 inhibited chronic inflammatory and neuropathic pain and reduced the depressive-like behaviors associated with persistent neuropathic pain. The antiallodynic effects of UFP-512 were significantly augmented when it was coadministered with SFN in both types of chronic pain. The administration of UFP-512 increased/reestablished the spinal cord protein levels of Nrf2 and HO-1 in mice with inflammatory or neuropathic pain. However, while during inflammatory pain UFP-512 inhibited spinal c-Jun N-terminal kinase (JNK) and extracellular signal regulated kinase 1/2 (ERK1/2) phosphorylation induced by peripheral inflammation. This DOR agonist blocked the spinal activated PI3K/Akt signaling pathway under chronic neuropathic pain conditions, but it did not alter the enhanced protein levels of p-JNK or p-ERK1/2 induced by sciatic nerve injury. These results revealed the antinociceptive and antidepressant effects of UFP-512 in animals with chronic pain and the different mechanism of action of this DOR agonist in the presence of inflammatory or neuropathic pain. Our data also suggest the administration of UFP-512 as an alternative for the treatment of chronic pain and the depressive-like behaviors associated with neuropathic pain.
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Affiliation(s)
- Sara Polo
- Grup de Neurofarmacologia Molecular, Institut d'Investigació Biomèdica Sant Pau, Barcelona, Spain.,Grup de Neurofarmacologia Molecular, Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Andrés Felipe Díaz
- Grup de Neurofarmacologia Molecular, Institut d'Investigació Biomèdica Sant Pau, Barcelona, Spain.,Grup de Neurofarmacologia Molecular, Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Núria Gallardo
- Grup de Neurofarmacologia Molecular, Institut d'Investigació Biomèdica Sant Pau, Barcelona, Spain.,Grup de Neurofarmacologia Molecular, Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Sergi Leánez
- Grup de Neurofarmacologia Molecular, Institut d'Investigació Biomèdica Sant Pau, Barcelona, Spain.,Grup de Neurofarmacologia Molecular, Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Gianfranco Balboni
- Department of Life and Environmental Sciences, Unit of Pharmaceutical, Pharmacological and Nutraceutical Sciences, University of Cagliari, Cagliari, Italy
| | - Olga Pol
- Grup de Neurofarmacologia Molecular, Institut d'Investigació Biomèdica Sant Pau, Barcelona, Spain.,Grup de Neurofarmacologia Molecular, Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain
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12
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Zhang T, Zhao W, Zhang M, Xu B, Shi X, Zhang Q, Guo Y, Xiao J, Chen D, Zheng T, Fang Q. Analgesic activities of the mixed opioid and NPFF receptors agonist DN-9 in a mouse model of formalin-induced orofacial inflammatory pain. Peptides 2018; 110:30-39. [PMID: 30391423 DOI: 10.1016/j.peptides.2018.10.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Revised: 10/13/2018] [Accepted: 10/29/2018] [Indexed: 11/20/2022]
Abstract
Orofacial pain is one of the most common pain conditions and compromises the quality of life of the sufferer. Several studies have shown that opioid agonists produced significant analgesia in the orofacial pain, and combination of opioids with drugs belonging to other classes induced synergism in the orofacial pain. However, combination therapy of different analgesic drugs improves the risk of drug-drug interactions. Against this background, we sought to investigate the analgesic effects of the multi-functional opioid peptide DN-9, a mixed opioid and NPFF receptors agonist that produced robust analgesia in acute and inflammatory pain models, on formalin-induced orofacial pain. Our results showed that formalin injection caused significant spontaneous pain behaviors and increased the expressions of the mu-opioid receptor, c-Fos and phosphorylated extracellular signal-regulated kinase (p-ERK1/2) in the ipsilateral trigeminal ganglion (TG). In mice pretreated with DN-9, there was a significant reduction in nociceptive behaviors, which was selectively mediated by the mu- and kappa-opioid receptors, independently of the NPFF system. Four hours after formalin injection, the level of c-Fos immunoreactivity in the ipsilateral TG neurons was much lower in mice pretreated with DN-9 or morphine. In addition, DN-9 exhibited a significant inhibition in the expression of p-ERK1/2, which was reversed by the selective antagonists of the mu- and kappa-opioid receptors. In conclusion, our present results demonstrate that central administration of DN-9 produces potential antinociceptive effects via the mu- and kappa-opioid receptors, independently of the NPFF system, and this antinociceptive action is tightly linked with the intracellular ERK activation in TG neurons.
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Affiliation(s)
- Ting Zhang
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, and Institute of Physiology, School of Basic Medical Sciences, Lanzhou University, 199 Donggang West Road, Lanzhou, 730000, China
| | - Weidong Zhao
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, and Institute of Physiology, School of Basic Medical Sciences, Lanzhou University, 199 Donggang West Road, Lanzhou, 730000, China
| | - Mengna Zhang
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, and Institute of Physiology, School of Basic Medical Sciences, Lanzhou University, 199 Donggang West Road, Lanzhou, 730000, China
| | - Biao Xu
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, and Institute of Physiology, School of Basic Medical Sciences, Lanzhou University, 199 Donggang West Road, Lanzhou, 730000, China
| | - Xuerui Shi
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, and Institute of Physiology, School of Basic Medical Sciences, Lanzhou University, 199 Donggang West Road, Lanzhou, 730000, China
| | - Qinqin Zhang
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, and Institute of Physiology, School of Basic Medical Sciences, Lanzhou University, 199 Donggang West Road, Lanzhou, 730000, China
| | - Yuanyuan Guo
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, and Institute of Physiology, School of Basic Medical Sciences, Lanzhou University, 199 Donggang West Road, Lanzhou, 730000, China
| | - Jian Xiao
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, and Institute of Physiology, School of Basic Medical Sciences, Lanzhou University, 199 Donggang West Road, Lanzhou, 730000, China
| | - Dan Chen
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, and Institute of Physiology, School of Basic Medical Sciences, Lanzhou University, 199 Donggang West Road, Lanzhou, 730000, China
| | - Ting Zheng
- Department of Clinical Medicine, Gansu Health Vocational College, 60 Donggang West Road, Lanzhou 730000, China
| | - Quan Fang
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, and Institute of Physiology, School of Basic Medical Sciences, Lanzhou University, 199 Donggang West Road, Lanzhou, 730000, China.
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13
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Liu B, Liu Y, Li N, Zhang J, Zhang X. Oxycodone regulates incision-induced activation of neurotrophic factors and receptors in an acute post-surgery pain rat model. J Pain Res 2018; 11:2663-2674. [PMID: 30464584 PMCID: PMC6214342 DOI: 10.2147/jpr.s180396] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Background Oxycodone, which is one of the most commonly used opiates in postoperative pain management, has a different affinity for μ-opioid receptors (MOR), κ-opioid receptors (KOR), and δ-opioid receptors (DOR). Accumulating research has suggested that neurotrophins (NTs) are involved in opioid analgesia. In the current exploratory study, we aimed to investigate the underlying mechanisms of the analgesic effects of oxycodone on post-surgery pain in rats and to determine whether neurotrophic factors and receptors were involved in these effects. Methods Mechanical and thermal sensitivity tests were used to evaluate the validity of the postoperative pain rat model and to determine the analgesic effect of oxycodone. Quantitative PCR and Western blot analysis were used to detect the changes in the expression of three types of opioid receptors and NTs and their high-affinity receptors in the spinal cord after surgery and oxycodone administration. Results Oxycodone showed an analgesic effect on plantar incision (PI)-induced hyperalgesia, especially thermal hyperalgesia. We detected an obvious increase in MOR expression levels but insignificant changes in KOR and DOR levels in the spinal cord after PI. Moreover, we found that oxycodone was able to reverse the increased expression of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), tyrosine kinase receptor (TrK) A, and TrkB and the decreased expression of NT-3 and TrkC, after PI. Pretreatment with oxycodone also altered the expression of these mediators. Conclusion Based on the results, possible underlying mechanisms for the antinociceptive properties of oxycodone in acute postoperative pain include the activation of MOR downstream signaling and the regulation of NTs and receptor expression through attenuation of glial activation and fortification of antinociceptive mediators in the spinal cord. This study may provide new insights into the molecular mechanisms underlying the analgesic action of oxycodone.
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Affiliation(s)
- Baowen Liu
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China,
| | - Yi Liu
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China,
| | - Ningbo Li
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China,
| | - Jin Zhang
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China,
| | - Xianwei Zhang
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China,
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Kang SK, Lee YH, Park H, Ro JY, Auh QS. Effects of intramuscular morphine in men and women with temporomandibular disorder with myofascial pain. Oral Dis 2018; 24:1591-1598. [PMID: 29920852 DOI: 10.1111/odi.12919] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 05/30/2018] [Accepted: 06/08/2018] [Indexed: 11/28/2022]
Abstract
OBJECTIVES This placebo-controlled randomized double-blinded clinical study assessed the analgesic efficacy of intramuscular morphine in TMD patients with myofascial pain and sex-dependent responses of the morphine treatment. SUBJECTS AND METHODS Men and women with TMD were treated with morphine (1.5 or 5 mg), lidocaine, or saline in the masseter muscle. VAS of pain intensity, PPT, and PPtol were compared between treatment groups and gender. An additional group was treated with morphine in the trapezius muscle to evaluate the systemic effect of morphine that may reduce pain in the masseter muscle. RESULTS There was a significant difference in VAS scores between the morphine 5 mg group and the saline group favoring morphine, but not between the morphine 5 mg and lidocaine. Morphine 1.5 and 5 mg treatments led to consistently and significantly elevated PPT and PPtol measures in men, but not in women. Morphine administered in the trapezius muscle did not affect the outcome measures. CONCLUSION A single dose intramuscular morphine produced analgesic effects up to 48 hr in patients with myofascial pain. Intramuscular morphine elevated mechanical pain threshold and tolerance in the masseter only in male patients, suggesting sex differences in local morphine effects. No systemic effect of intramuscular morphine was detected.
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Affiliation(s)
- Soo-Kyung Kang
- Department of Oral Medicine, School of Dentistry, Kyung Hee University, Seoul, Korea
| | - Yeon-Hee Lee
- Department of Oral Medicine, School of Dentistry, Kyung Hee University, Seoul, Korea
| | - Hyeji Park
- Department of Dentistry, Graduate School, Kyung Hee University, Seoul, Korea
| | - Jin Y Ro
- Department of Oral Medicine, School of Dentistry, Kyung Hee University, Seoul, Korea.,Department of Neural and Pain Sciences, Program in Neuroscience, University of Maryland School of Dentistry, Baltimore, Maryland
| | - Q-Schick Auh
- Department of Oral Medicine, School of Dentistry, Kyung Hee University, Seoul, Korea
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15
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Abstract
Nowadays, the delta opioid receptor (DOPr) represents a promising target for the treatment of chronic pain and emotional disorders. Despite the fact that they produce limited antinociceptive effects in healthy animals and in most acute pain models, DOPr agonists have shown efficacy in various chronic pain models. In this chapter, we review the progresses that have been made over the last decades in understanding the role played by DOPr in the control of pain. More specifically, the distribution of DOPr within the central nervous system and along pain pathways is presented. We also summarize the literature supporting a role for DOPr in acute, tonic, and chronic pain models, as well as the mechanisms regulating its activity under specific conditions. Finally, novel compounds that have make their way to clinical trials are discussed.
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Affiliation(s)
- Khaled Abdallah
- Département de pharmacologie-physiologie, Université de Sherbrooke, Sherbrooke, QC, Canada
- Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC, Canada
- Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, QC, Canada
- Centre de recherche du CHUS, Sherbrooke, QC, Canada
| | - Louis Gendron
- Département de pharmacologie-physiologie, Université de Sherbrooke, Sherbrooke, QC, Canada.
- Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC, Canada.
- Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, QC, Canada.
- Centre de recherche du CHUS, Sherbrooke, QC, Canada.
- Département d'anesthésiologie, Université de Sherbrooke, Sherbrooke, QC, Canada.
- Quebec Pain Research Network, Sherbrooke, QC, Canada.
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16
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Gendron L, Cahill CM, von Zastrow M, Schiller PW, Pineyro G. Molecular Pharmacology of δ-Opioid Receptors. Pharmacol Rev 2017; 68:631-700. [PMID: 27343248 DOI: 10.1124/pr.114.008979] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Opioids are among the most effective analgesics available and are the first choice in the treatment of acute severe pain. However, partial efficacy, a tendency to produce tolerance, and a host of ill-tolerated side effects make clinically available opioids less effective in the management of chronic pain syndromes. Given that most therapeutic opioids produce their actions via µ-opioid receptors (MOPrs), other targets are constantly being explored, among which δ-opioid receptors (DOPrs) are being increasingly considered as promising alternatives. This review addresses DOPrs from the perspective of cellular and molecular determinants of their pharmacological diversity. Thus, DOPr ligands are examined in terms of structural and functional variety, DOPrs' capacity to engage a multiplicity of canonical and noncanonical G protein-dependent responses is surveyed, and evidence supporting ligand-specific signaling and regulation is analyzed. Pharmacological DOPr subtypes are examined in light of the ability of DOPr to organize into multimeric arrays and to adopt multiple active conformations as well as differences in ligand kinetics. Current knowledge on DOPr targeting to the membrane is examined as a means of understanding how these receptors are especially active in chronic pain management. Insight into cellular and molecular mechanisms of pharmacological diversity should guide the rational design of more effective, longer-lasting, and better-tolerated opioid analgesics for chronic pain management.
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Affiliation(s)
- Louis Gendron
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Catherine M Cahill
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Mark von Zastrow
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Peter W Schiller
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
| | - Graciela Pineyro
- Département de Pharmacologie-Physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Centre de Recherche du CHU de Sherbrooke, Centre d'excellence en neurosciences de l'Univeristé de Sherbrooke, and Institut de Pharmacologie de Sherbrooke, Sherbrooke, Quebec, Canada (L.G.); Québec Pain Research Network, Sherbrooke, Quebec, Canada (L.G.); Departments of Anesthesiology and Perioperative Care and Pharmacology, University of California, Irvine, California (C.M.C.); Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada (C.M.C.); Departments of Psychiatry and Cellular and Molecular Pharmacology, University of California, San Francisco, California (M.v.Z.); Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, Montreal, Quebec, Canada (P.W.S.); and Departments of Psychiatry, Pharmacology, and Neurosciences, Faculty of Medicine, University of Montréal and Sainte-Justine Hospital Research Center, Montreal, Quebec, Canada (G.P.)
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17
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François A, Scherrer G. Delta Opioid Receptor Expression and Function in Primary Afferent Somatosensory Neurons. Handb Exp Pharmacol 2017; 247:87-114. [PMID: 28993838 DOI: 10.1007/164_2017_58] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The functional diversity of primary afferent neurons of the dorsal root ganglia (DRG) generates a variety of qualitatively and quantitatively distinct somatosensory experiences, from shooting pain to pleasant touch. In recent years, the identification of dozens of genetic markers specifically expressed by subpopulations of DRG neurons has dramatically improved our understanding of this diversity and provided the tools to manipulate their activity and uncover their molecular identity and function. Opioid receptors have long been known to be expressed by discrete populations of DRG neurons, in which they regulate cell excitability and neurotransmitter release. We review recent insights into the identity of the DRG neurons that express the delta opioid receptor (DOR) and the ion channel mechanisms that DOR engages in these cells to regulate sensory input. We highlight recent findings derived from DORGFP reporter mice and from in situ hybridization and RNA sequencing studies in wild-type mice that revealed DOR presence in cutaneous mechanosensory afferents eliciting touch and implicated in tactile allodynia. Mechanistically, we describe how DOR modulates opening of voltage-gated calcium channels (VGCCs) to control glutamatergic neurotransmission between somatosensory neurons and postsynaptic neurons in the spinal cord dorsal horn. We additionally discuss other potential signaling mechanisms, including those involving potassium channels, which DOR may engage to fine tune somatosensation. We conclude by discussing how this knowledge may explain the analgesic properties of DOR agonists against mechanical pain and uncovers an unanticipated specialized function for DOR in cutaneous mechanosensation.
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Affiliation(s)
- Amaury François
- Department of Anesthesiology, Perioperative and Pain Medicine, Stanford Neurosciences Institute, Stanford University School of Medicine, Palo Alto, CA, USA.,Department of Molecular and Cellular Physiology, Stanford Neurosciences Institute, Stanford University School of Medicine, Palo Alto, CA, USA.,Department of Neurosurgery, Stanford Neurosciences Institute, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Grégory Scherrer
- Department of Anesthesiology, Perioperative and Pain Medicine, Stanford Neurosciences Institute, Stanford University School of Medicine, Palo Alto, CA, USA. .,Department of Molecular and Cellular Physiology, Stanford Neurosciences Institute, Stanford University School of Medicine, Palo Alto, CA, USA. .,Department of Neurosurgery, Stanford Neurosciences Institute, Stanford University School of Medicine, Palo Alto, CA, USA.
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18
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de Oliveira Junior JO, de Freitas MF, Bullara de Andrade C, Chacur M, Ashmawi HA. Local analgesic effect of tramadol is mediated by opioid receptors in late postoperative pain after plantar incision in rats. J Pain Res 2016; 9:797-802. [PMID: 27799813 PMCID: PMC5074711 DOI: 10.2147/jpr.s117674] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Tramadol is a drug used to treat moderate to severe pain. It is known to present a peripheral effect, but the local mechanisms underlying its actions remain unclear. The role of peripheral opioid receptors in postoperative pain is not well understood. In the present study, we examined the peripheral opioid receptors to determine the local effect of tramadol in a plantar incision pain model. Rats were subjected to plantar incision and divided into four groups on postoperative day (POD) 1: SF_SF, 0.9% NaCl injected into the right hindpaw; SF_TraI, 0.9% NaCl and tramadol injected into the right hindpaw; SF_TraC, 0.9% NaCl and tramadol injected into the contralateral hindpaw; and Nal_Tra, naloxone and tramadol injected into the ipsilateral hindpaw. To determine the animals' nociceptive threshold, mechanical hyperalgesia was measured before incision, on POD1 before treatment and at 15, 30, 45, and 60 minutes after the incision. The same procedure was repeated on the POD2. The expression levels of μ-opioid receptor (MOR) and δ-opioid receptor (DOR) were obtained through immunoblotting assays in the lumbar dorsal root ganglia (L3-L6) in naïve rats and 1, 2, 3, and 7 days after the incision. Our results showed that the plantar incision was able to cause an increase in mechanical hyperalgesia and that tramadol reversed this hyperalgesia on POD1 and POD2. Tramadol injections in the contralateral paw did not affect the animals' nociceptive threshold. Naloxone was able to antagonize the tramadol effect partially on POD1 and completely on POD2. The DOR expression increased on POD2, POD3, and POD7, whereas the MOR expression did not change. Together, our results show that tramadol promoted a local analgesic effect in the postoperative pain model that was antagonized by naloxone in POD2, alongside the increase of DOR expression.
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Affiliation(s)
| | | | | | - Marucia Chacur
- Departamento de Anatomia do Instituto de Ciências Biomédicas da Universidade de São Paulo
| | - Hazem Adel Ashmawi
- Laboratório de Anestesiologia Experimental, Faculdade de Medicina da Universidade de São Paulo
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Sousa AM, Ashmawi HA. Local analgesic effect of tramadol is not mediated by opioid receptors in early postoperative pain in rats. Braz J Anesthesiol 2015; 65:186-90. [PMID: 25925030 DOI: 10.1016/j.bjane.2014.06.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2014] [Accepted: 06/26/2014] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND AND OBJECTIVES Tramadol is known as a central acting analgesic drug, used for the treatment of moderate to severe pain. Local analgesic effect has been demonstrated, in part due to local anesthetic-like effect, but other mechanisms remain unclear. The role of peripheral opioid receptors in the local analgesic effect is not known. In this study, we examined role of peripheral opioid receptors in the local analgesic effect of tramadol in the plantar incision model. METHODS Young male Wistar rats were divided into seven groups: control, intraplantar tramadol, intravenous tramadol, intravenous naloxone-intraplantar tramadol, intraplantar naloxone-intraplantar tramadol, intravenous naloxone-intravenous tramadol, and intravenous naloxone. After receiving the assigned drugs (tramadol 5mg, naloxone 200 μg or 0.9% NaCl), rats were submitted to plantar incision, and withdrawal thresholds after mechanical stimuli with von Frey filaments were assessed at baseline, 10, 15, 30, 45 and 60 min after incision. RESULTS Plantar incision led to marked mechanical hyperalgesia during the whole period of observation in the control group, no mechanical hyperalgesia were observed in intraplantar tramadol group, intraplantar naloxone-intraplantar tramadol group and intravenous naloxone-intraplantar tramadol. In the intravenous tramadol group a late increase in withdrawal thresholds (after 45 min) was observed, the intravenous naloxone-intravenous tramadol group and intravenous naloxone remained hyperalgesic during the whole period. CONCLUSIONS Tramadol presented an early local analgesic effect decreasing mechanical hyperalgesia induced by plantar incision. This analgesic effect was not mediated by peripheral opioid receptors.
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Affiliation(s)
- Angela Maria Sousa
- Faculdade de Medicina da USP, Laboratório de Investigação Médica - LIM-08, São Paulo, SP, Brazil
| | - Hazem Adel Ashmawi
- Faculdade de Medicina da USP, Laboratório de Investigação Médica - LIM-08, São Paulo, SP, Brazil.
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Sousa AM, Ashmawi HA. [Local analgesic effect of tramadol is not mediated by opioid receptors in early postoperative pain in rats]. Rev Bras Anestesiol 2015; 65:186-90. [PMID: 25842002 DOI: 10.1016/j.bjan.2014.06.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2014] [Accepted: 06/26/2014] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND AND OBJECTIVES Tramadol is known as a central acting analgesic drug, used for the treatment of moderate to severe pain. Local analgesic effect has been demonstrated, in part due to local anesthetic-like effect, but other mechanisms remain unclear. The role of peripheral opioid receptors in the local analgesic effect is not known. In this study, we examined role of peripheral opioid receptors in the local analgesic effect of tramadol in the plantar incision model. METHODS Young male Wistar rats were divided into seven groups: control, intraplantar tramadol, intravenous tramadol, intravenous naloxone-intraplantar tramadol, intraplantar naloxone-intraplantar tramadol, intravenous naloxone-intravenous tramadol, and intravenous naloxone. After receiving the assigned drugs (tramadol 5mg, naloxone 200μg or 0.9% NaCl), rats were submitted to plantar incision, and withdrawal thresholds after mechanical stimuli with von Frey filaments were assessed at baseline, 10, 15, 30, 45 and 60min after incision. RESULTS Plantar incision led to marked mechanical hyperalgesia during the whole period of observation in the control group, no mechanical hyperalgesia were observed in intraplantar tramadol group, intraplantar naloxone-intraplantar tramadol group and intravenous naloxone-intraplantar tramadol. In the intravenous tramadol group a late increase in withdrawal thresholds (after 45min) was observed, the intravenous naloxone-intravenous tramadol group and intravenous naloxone remained hyperalgesic during the whole period. CONCLUSIONS Tramadol presented an early local analgesic effect decreasing mechanical hyperalgesia induced by plantar incision. This analgesic effect was not mediated by peripheral opioid receptors.
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Affiliation(s)
- Angela Maria Sousa
- Laboratório de Investigação Médica (LIM-08), Faculdade de Medicina da Universidade de São Paulo (USP), São Paulo, SP, Brasil
| | - Hazem Adel Ashmawi
- Laboratório de Investigação Médica (LIM-08), Faculdade de Medicina da Universidade de São Paulo (USP), São Paulo, SP, Brasil.
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Rohrs EL, Kloefkorn HE, Lakes EH, Jacobs BY, Neubert JK, Caudle RM, Allen KD. A novel operant-based behavioral assay of mechanical allodynia in the orofacial region of rats. J Neurosci Methods 2015; 248:1-6. [PMID: 25823368 DOI: 10.1016/j.jneumeth.2015.03.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 03/18/2015] [Accepted: 03/20/2015] [Indexed: 01/09/2023]
Abstract
BACKGROUND Detecting behaviors related to orofacial pain in rodent models often relies on subjective investigator grades or methods that place the animal in a stressful environment. In this study, an operant-based behavioral assay is presented for the assessment of orofacial tactile sensitivity in the rat. NEW METHODS In the testing chamber, rats are provided access to a sweetened condensed milk bottle; however, a 360° array of stainless steel wire loops impedes access. To receive the reward, an animal must engage the wires across the orofacial region. Contact with the bottle triggers a motor, requiring the animal to accept increasing pressure on the face during the test. To evaluate this approach, tolerated bottle distance was measured for 10 hairless Sprague Dawley rats at baseline and 30 min after application of capsaicin cream (0.1%) to the face. The experiment was repeated to evaluate the ability of morphine to reverse this effect. RESULTS The application of capsaicin cream reduced tolerated bottle distance measures relative to baseline (p<0.05). As long as morphine did not cause reduced participation due to sedation, subcutaneous morphine dosing reduced the effects of capsaicin (p<0.001). Comparison with existing method: For behavioral tests, experimenters often make subjective decisions of an animal's response. Operant methods can reduce these effects by measuring an animal's selection in a reward-conflict decision. Herein, a method to measure orofacial sensitivity is presented using an operant system. CONCLUSIONS This operant device allows for consistent measurement of heightened tactile sensitivity in the orofacial regions of the rat.
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Affiliation(s)
- Eric L Rohrs
- J Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, 1275 Center Drive Biomedical Sciences Building, JG56, Gainesville, FL, 32610, United States.
| | - Heidi E Kloefkorn
- J Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, 1275 Center Drive Biomedical Sciences Building, JG56, Gainesville, FL, 32610, United States.
| | - Emily H Lakes
- J Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, 1275 Center Drive Biomedical Sciences Building, JG56, Gainesville, FL, 32610, United States; Institute for Cell Engineering and Regenerative Medicine, University of Florida, Gainesville, FL, United States.
| | - Brittany Y Jacobs
- J Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, 1275 Center Drive Biomedical Sciences Building, JG56, Gainesville, FL, 32610, United States.
| | - John K Neubert
- Department of Orthodontics, University of Florida, Gainesville, FL, United States; Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, FL, United States.
| | - Robert M Caudle
- Department of Oral and Maxillofacial Surgery, University of Florida, Gainesville, FL, United States; Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, FL, United States.
| | - Kyle D Allen
- J Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, 1275 Center Drive Biomedical Sciences Building, JG56, Gainesville, FL, 32610, United States; Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, FL, United States; Institute for Cell Engineering and Regenerative Medicine, University of Florida, Gainesville, FL, United States; Nanoscience Institute for Medical and Engineering Technology, University of Florida, Gainesville, FL, United States.
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Bai X, Zhang X, Li Y, Lu L, Li B, He X. Sex differences in peripheral mu-opioid receptor mediated analgesia in rat orofacial persistent pain model. PLoS One 2015; 10:e0122924. [PMID: 25807259 PMCID: PMC4373836 DOI: 10.1371/journal.pone.0122924] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Accepted: 02/16/2015] [Indexed: 02/01/2023] Open
Abstract
Unilateral ligation of the tendon of anterior superficial part of rat masseter muscle (TASM) leads to long-lasting allodynia. Sex differences in peripheral mu-opioid receptor (MOR)-mediated analgesia under persistent myogenic pain are not well understood. In this study, we examined (1) whether locally applied MOR agonists attenuate persistent pain following TASM ligation in a sex dependent manner, (2) whether there are sex differences of MOR expression changes in rat trigeminal ganglia (TG). The effects of MOR agonist, D-Ala2, N-Me-Phe4, Gly5-ol]-Enkephalin acetate salt (DAMGO), were assessed 14 days after TASM ligation in male, female and orchidectomized (GDX) male rats. MOR mRNA and protein levels in TG 14 days following tendon ligation were also determined. The mechanical thresholds of the injured side were significantly decreased in both male and female rats, from 3 days to 28 days after TASM ligation. A10 μg DAMGO significantly attenuated allodynia in male rats. A 10-fold higher dose of DAMGO was required in female and GDX male rats to produce the level of anti- allodynia achieved in male rats. The level of MOR mRNA in TG from male rats was significantly greater 14 days after TASM ligation compared with the sham-operated male rats, but not from female and GDX male rats. After TASM ligation, males had significantly more MOR immunoreactivity in TG compared to sham-operated males. The MOR levels increased to 181.8% of the sham level in male rats receiving tendon injury. But there was no significant change in female rats receiving tendon injury compared to the sham female rats. Taken together, our data suggest that there were sex differences in the effects of peripheral MOR agonists between male and female rats under TASM ligation developing long-lasting pain condition, which is partly mediated by sex differences in the changes of MOR expressions and testosterone is an important factor in the regulation of MOR.
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MESH Headings
- Analgesics, Opioid/pharmacology
- Analgesics, Opioid/therapeutic use
- Animals
- Behavior, Animal/drug effects
- Disease Models, Animal
- Enkephalin, Ala(2)-MePhe(4)-Gly(5)-/pharmacology
- Enkephalin, Ala(2)-MePhe(4)-Gly(5)-/therapeutic use
- Facial Pain/drug therapy
- Facial Pain/etiology
- Facial Pain/veterinary
- Female
- Hyperalgesia/drug therapy
- Hyperalgesia/etiology
- Hyperalgesia/pathology
- Immunohistochemistry
- Male
- Orchiectomy
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Real-Time Polymerase Chain Reaction
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/genetics
- Receptors, Opioid, mu/metabolism
- Sex Characteristics
- Tendon Injuries/complications
- Tendon Injuries/pathology
- Trigeminal Ganglion/metabolism
- Trigeminal Ganglion/pathology
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Affiliation(s)
- Xiaofeng Bai
- Associate Professor, Department of Oral and Maxillofacial Surgery, School & Hospital of Stomatology, China Medical University, 117 North Nanjing Street, Shenyang, P. R. of China, 110002
- * E-mail: (XZ); (XB)
| | - Xia Zhang
- Associate Professor, Department of Anesthesiology, School & Hospital of Stomatology, China Medical University, 117 North Nanjing Street, Shenyang, P. R. of China, 110002
- * E-mail: (XZ); (XB)
| | - Yanshu Li
- Assistant Professor, Department of Cell Biology, China Medical University, 92 Bei'er Road, Shenyang, P. R. of China, 110001
| | - Li Lu
- Professor, Department of Oral and Maxillofacial Surgery, School & Hospital of Stomatology, China Medical University, 117 North Nanjing Street, Shenyang, P. R. of China, 110002
| | - Bo Li
- Associate Professor, Department of Oral Anatomy and Physiology, School of Stomatology, China Medical University, 117 North Nanjing Street, Shenyang, P. R. of China, 110002
| | - Xiaofan He
- Assistant Professor, Department of Anesthesiology, School & Hospital of Stomatology, China Medical University, 117 North Nanjing Street, Shenyang, P. R. of China, 110002
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Kramer PR, Umorin M, Bellinger LL. Attenuation of myogenic orofacial nociception and mechanical hypersensitivity by viral mediated enkephalin overproduction in male and female rats. BMC Neurol 2015; 15:34. [PMID: 25885338 PMCID: PMC4369359 DOI: 10.1186/s12883-015-0285-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 02/25/2015] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Clinical studies have tested the use of an engineered herpes virus to treat pain. We hypothesized that subcutaneous injections of an engineered herpes virus that expresses enkephalin would attenuate orofacial nociception and hypersensitivity in male and female rats by a central mechanism. METHODS Herpes virus was injected subcutaneously around the mouth of male and female rats seventy-two hours before ligatures were placed on the masseter tendon, control treatment groups received either no virus or no ligature. Enkephalin expression was measured and von Frey filament testing and meal duration were utilized to measure mechanical hypersensitivity and the nociceptive response, respectively. Naloxone or naloxone methiodide was administered to rats injected with the enkephalin expressing virus to test if enkephalin was acting peripherally or centrally. RESULTS Ligature significantly lengthened meal duration and reduced the threshold to von Frey filaments for 18 days. Infection with the enkephalin transgene significantly decreased this response for at least 11 days but only in male rats. Virus injection significantly increased expression of enkephalin in the mental nerve that innervates the mouth region, the trigeminal ganglia and the trigeminal nucleus caudalis but no increase was observed in the masseter nerve after virus injection. Naloxone but not naloxone methiodide reversed the response to the enkephaline expressing virus. CONCLUSIONS The data suggests that sex should be a considered when using this virus and that viral transfection of the mental nerve with an enkephalin transgene can reduce nociception and hypersensitivity through a central mechanism.
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Affiliation(s)
- Phillip R Kramer
- Department of Biomedical Sciences, Texas A&M University Baylor College of Dentistry, 3302 Gaston Avenue, Dallas, TX, 75246, USA.
| | - Mikhail Umorin
- Department of Biomedical Sciences, Texas A&M University Baylor College of Dentistry, 3302 Gaston Avenue, Dallas, TX, 75246, USA.
| | - Larry L Bellinger
- Department of Biomedical Sciences, Texas A&M University Baylor College of Dentistry, 3302 Gaston Avenue, Dallas, TX, 75246, USA.
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Rowan MP, Szteyn K, Doyle AP, Gomez R, Henry MA, Jeske NA. β-arrestin-2-biased agonism of delta opioid receptors sensitizes transient receptor potential vanilloid type 1 (TRPV1) in primary sensory neurons. Mol Pain 2014; 10:50. [PMID: 25085415 PMCID: PMC4131480 DOI: 10.1186/1744-8069-10-50] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 07/21/2014] [Indexed: 02/06/2023] Open
Abstract
Despite advances in understanding the signaling mechanisms involved in the development and maintenance of chronic pain, the pharmacologic treatment of chronic pain has seen little advancement. Agonists at the mu opioid receptor (MOPr) continue to be vital in the treatment of many forms of chronic pain, but side-effects limit their clinical utility and range from relatively mild, such as constipation, to major, such as addiction and dependence. Additionally, chronic activation of MOPr results in pain hypersensitivity known as opioid-induced hyperalgesia (OIH), and we have shown recently that recruitment of β-arrestin2 to MOPr, away from transient potential vanilloid eceptor type 1 (TRPV1) in primary sensory neurons contributes to this phenomenon. The delta opioid receptor (DOPr) has become a promising target for the treatment of chronic pain, but little is known about the effects of chronic activation of DOPr on nociceptor sensitivity and OIH. Here we report that chronic activation of DOPr by the DOPr-selective agonist, SNC80, results in the sensitization of TRPV1 and behavioral signs of OIH via β-arrestin2 recruitment to DOPr and away from TRPV1. Conversely, chronic treatment with ARM390, a DOPr-selective agonist that does not recruit β-arrestin2, neither sensitized TRPV1 nor produced OIH. Interestingly, the effect of SNC80 to sensitize TRPV1 is species-dependent, as rats developed OIH but mice did not. Taken together, the reported data identify a novel side-effect of chronic administration of β-arrestin2-biased DOPr agonists and highlight the importance of potential species-specific effects of DOPr agonists.
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Affiliation(s)
| | | | | | | | | | - Nathaniel A Jeske
- Departments of Oral and Maxillofacial Surgery, The University of Texas Health Science Center at San Antonio, MC 7908, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA.
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Zhang X, Zhang Y, Asgar J, Niu KY, Lee J, Lee KS, Schneider M, Ro JY. Sex differences in μ-opioid receptor expression in trigeminal ganglia under a myositis condition in rats. Eur J Pain 2014; 18:151-61. [PMID: 23801566 PMCID: PMC3916151 DOI: 10.1002/j.1532-2149.2013.00352.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/31/2013] [Indexed: 12/12/2022]
Abstract
BACKGROUND Peripheral opioid receptor expression is up-regulated under inflammatory conditions, which leads to the increased efficacy of peripherally administered opioids. Sex differences in the effects of inflammation, cytokines and gonadal hormones on μ-opioid receptor (MOR) expression in trigeminal ganglia (TG) are not well understood. METHODS MOR mRNA and protein levels in TG from male and female Sprague Dawley rats following complete Freund's adjuvant (CFA)-induced muscle inflammation were assessed. Cytokine-induced changes in MOR mRNA expression from TG cultures prepared from intact and gonadectomized male and female, and gonadectomized male rats with testosterone replacement were examined. Behavioural experiments were then performed to examine the efficacy of a peripherally administered MOR agonist in male, female and gonadectomized male rats under a myositis condition. RESULTS CFA and cytokine treatments induced significant up-regulation of MOR expression in TG from male, but not from female, rats. The cytokine-induced up-regulation of MOR mRNA expression was prevented in TG from orchidectomized (GDX) male rats, which was restored with testosterone replacement. Peripherally administered DAMGO, a specific MOR agonist, significantly attenuated CFA-induced masseter mechanical hypersensitivity only in intact male rats. CONCLUSIONS Collectively, these data indicate that testosterone plays a key role in the regulation of MOR in TG under inflammatory conditions, and that sex differences in the anti-hyperalgesic effects of peripherally administered opioids are, in part, mediated by peripheral opioid receptor expression levels.
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Affiliation(s)
- X Zhang
- China Medical University, Hospital of Stomatology, The First Affiliated Hospital, Department of Anesthesiology, Shenyang, 110002, China
| | - Y Zhang
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, 650 W. Baltimore St, Baltimore, MD 21201
| | - J Asgar
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, 650 W. Baltimore St, Baltimore, MD 21201
| | - KY Niu
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, 650 W. Baltimore St, Baltimore, MD 21201
| | - J Lee
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, 650 W. Baltimore St, Baltimore, MD 21201
| | - KS Lee
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, 650 W. Baltimore St, Baltimore, MD 21201
| | - M Schneider
- University of Maryland School of Dentistry, Department of Orthodontics, 650 W. Baltimore St, Baltimore, MD 21201
| | - JY Ro
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, 650 W. Baltimore St, Baltimore, MD 21201
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Pharmacological traits of delta opioid receptors: pitfalls or opportunities? Psychopharmacology (Berl) 2013; 228:1-18. [PMID: 23649885 PMCID: PMC3679311 DOI: 10.1007/s00213-013-3129-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Accepted: 04/15/2013] [Indexed: 12/11/2022]
Abstract
RATIONALE Delta opioid receptors (DORs) have been considered as a potential target to relieve pain as well as treat depression and anxiety disorders and are known to modulate other physiological responses, including ethanol and food consumption. A small number of DOR-selective drugs are in clinical trials, but no DOR-selective drugs have been approved by the Federal Drug Administration and some candidates have failed in phase II clinical trials, highlighting current difficulties producing effective delta opioid-based therapies. Recent studies have provided new insights into the pharmacology of the DOR, which is often complex and at times paradoxical. OBJECTIVE This review will discuss the existing literature focusing on four aspects: (1) Two DOR subtypes have been postulated based on differences in pharmacological effects of existing DOR-selective ligands. (2) DORs are expressed ubiquitously throughout the body and central nervous system and are, thus, positioned to play a role in a multitude of diseases. (3) DOR expression is often dynamic, with many reports of increased expression during exposure to chronic stimuli, such as stress, inflammation, neuropathy, morphine, or changes in endogenous opioid tone. (4) A large structural variety in DOR ligands implies potential different mechanisms of activating the receptor. CONCLUSION The reviewed features of DOR pharmacology illustrate the potential benefit of designing tailored or biased DOR ligands.
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Chung MK, Cho YS, Bae YC, Lee J, Zhang X, Ro JY. Peripheral G protein-coupled inwardly rectifying potassium channels are involved in δ-opioid receptor-mediated anti-hyperalgesia in rat masseter muscle. Eur J Pain 2013; 18:29-38. [PMID: 23740773 DOI: 10.1002/j.1532-2149.2013.00343.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/13/2013] [Indexed: 11/06/2022]
Abstract
BACKGROUND Although the efficacy of peripherally administered opioid has been demonstrated in preclinical and clinical studies, the underlying mechanisms of its anti-hyperalgesic effects are poorly understood. G protein-coupled inwardly rectifying potassium (GIRK) channels are linked to opioid receptors in the brain. However, the role of peripheral GIRK channels in analgesia induced by peripherally administered opioid, especially in trigeminal system, is not clear. METHODS Expression of GIRK subunits in rat trigeminal ganglia (TG) was examined with reverse transcription-polymerase chain reaction, Western blot and immunohistochemistry. Chemical profiles of GIRK-expressing neurons in TG were further characterized. Behavioural and Fos experiments were performed to examine the functional involvement of GIRK channels in δ-opioid receptor (DOR)-mediated anti-hyperalgesia under an acute myositis condition. RESULTS TG expressed mRNA and proteins for GIRK1 and GIRK2 subunits. Majority of GIRK1- and GIRK2-expressing neurons were non-peptidergic afferents. Inhibition of peripheral GIRK using Tertiapin-Q (TPQ) attenuated antinociceptive effects of peripherally administered DOR agonist, [D-Pen(2), D-Pen(6) ]-enkephalin (DPDPE), on mechanical hypersensitivity in masseter muscle. Furthermore, TPQ attenuated the suppressive effects of peripheral DPDPE on neuronal activation in the subnucleus caudalis of the trigeminal nucleus (Vc) following masseteric injection of capsaicin. CONCLUSIONS Our data indicate that peripheral DOR agonist-induced suppression of mechanical hypersensitivity in the masseter muscle involves the activity of peripheral GIRK channels. These results could provide a rationale for developing a novel therapeutic approach using peripheral GIRK channel openers to mimic or supplement the effects of peripheral opioid agonist.
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Affiliation(s)
- M-K Chung
- Department of Neural and Pain Sciences, University of Maryland School of Dentistry, Baltimore, USA
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Abstract
This paper is the thirty-fourth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2011 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration (Section 16); and immunological responses (Section 17).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY 11367, United States.
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30
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Abstract
Musculoskeletal pain conditions, particularly those associated with temporomandibular disorders (TMD) affect a large percentage of the population. Identifying mechanisms underlying hyperalgesia could contribute to the development of new treatment strategies for the management of TMD and other muscle pain conditions. In this study, we provide evidence of functional interactions between two ligand-gated channels, P2X₃ and transient receptor potential V1 (TRPV1), in trigeminal sensory neurons, and propose that the interactions serve as an underlying mechanism for the development of mechanical hyperalgesia. Mechanical sensitivity of the masseter muscle was assessed in lightly anesthetized rats via an electronic anesthesiometer (Ro et al., 2009). Direct intramuscular injection of a selective P2X₃ agonist, alpha,beta-methylene adenosine triphosphate (αβmeATP), induced a dose- and time-dependent hyperalgesia. Mechanical sensitivity in the contralateral muscle was unaffected suggesting local P2X₃ mediate hyperalgesia. Anesthetizing the overlying skin had no effect on αβmeATP-induced hyperalgesia confirming the contribution of P2X₃ from the muscle. Importantly, the αβmeATP-induced hyperalgesia was prevented by pretreatment of the muscle with a TRPV1 antagonist, AMG9810. P2X₃ was co-expressed with TRPV1 in the masseter muscle afferents confirming the possibility for intracellular interactions. Additionally, in a subpopulation of P2Xv/TRPV1 positive neurons, capsaicin-induced Ca(2+) transients were significantly amplified following P2X₃ activation. Finally, activation of P2X₃ induced phosphorylation of serine, but not threonine, residues in TRPV1 in trigeminal ganglia cultures. Significant phosphorylation was observed at 15 min, the time point at which behavioral hyperalgesia was prominent. Previously, activation of either P2X₃ or TRPV1 had been independently implicated in the development of mechanical hyperalgesia. Our data propose P2X₃ and TRPV1 interact in a facilitatory manner, which could contribute to the peripheral sensitization known to underlie masseter hyperalgesia.
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31
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Auh QS, Ro JY. Effects of peripheral κ opioid receptor activation on inflammatory mechanical hyperalgesia in male and female rats. Neurosci Lett 2012; 524:111-5. [PMID: 22819973 DOI: 10.1016/j.neulet.2012.07.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 07/02/2012] [Accepted: 07/11/2012] [Indexed: 12/30/2022]
Abstract
Activation of peripheral κ opioid receptors (KOR) effectively relieves pain and hyperalgesia in preclinical and clinical models of pain. Although centrally located KOR activation results in sexually dimorphic effects, it is unclear whether peripheral KOR also produces sex dependent effects in persistent inflammatory pain conditions. In this study, we investigated whether local administration of a specific KOR agonist, U50, 488 relieve mechanical hyperalgesia induced by the injection of complete Freund's adjuvant (CFA) in the rat hindpaw, and whether there are sex differences. The effects of U50, 488 were assessed three days after the induction of CFA-induced inflammation, a time point at which mechanical hyperalgesia was most prominent. There were no sex differences in baseline and CFA-induced changes in mechanical thresholds between male and female rats. Local treatment of U50, 488 produced moderate, but significant, anti-hyperalgesia in both male and female rats. However, U50, 488 was significantly more effective in male rats at the highest dose of U50, 488. We confirmed that the highest dose of U50, 488 used in this study did not produce systemic effects, and that the drug effect is receptor specific. On the basis of these results, we suggest that local KOR agonists are effective in mitigating mechanical hyperalgesia under a persistent inflammatory pain condition and that sex differences in anti-hyperalgesic effects become more evident at high doses.
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Affiliation(s)
- Q-Schick Auh
- Kyung Hee University School of Dentistry, Department of Oral Medicine, Hoegi Dong, Dongdaemun Gu, Seoul, Republic of Korea
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32
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Delta opioid receptor analgesia: recent contributions from pharmacology and molecular approaches. Behav Pharmacol 2011; 22:405-14. [PMID: 21836459 DOI: 10.1097/fbp.0b013e32834a1f2c] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Delta opioid receptors represent a promising target for the development of novel analgesics. A number of tools have been developed recently that have significantly improved our knowledge of δ receptor function in pain control. These include several novel δ agonists with potent analgesic properties, and genetic mouse models with targeted mutations in the δ opioid receptor gene. Also, recent findings have further documented the regulation of δ receptor function at cellular level, which impacts on the pain-reducing activity of the receptor. These regulatory mechanisms occur at transcriptional and post-translational levels, along agonist-induced receptor activation, signaling and trafficking, or in interaction with other receptors and neuromodulatory systems. All these tools for in-vivo research, and proposed mechanisms at molecular level, have tremendously increased our understanding of δ receptor physiology, and contribute to designing innovative strategies for the treatment of chronic pain and other diseases such as mood disorders.
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Niu K, Saloman JL, Zhang Y, Ro JY. Sex differences in the contribution of ATP-sensitive K+ channels in trigeminal ganglia under an acute muscle pain condition. Neuroscience 2011; 180:344-52. [PMID: 21296645 DOI: 10.1016/j.neuroscience.2011.01.045] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 01/20/2011] [Accepted: 01/20/2011] [Indexed: 11/25/2022]
Abstract
In this study, we examined whether functional subunits of the ATP-dependent K+ channel (KATP) are expressed in trigeminal ganglia (TG), which contains sensory neurons that innervate oral and facial structures. We also investigated whether direct activation of the KATP effectively attenuates mechanical hypersensitivity in the context of an acute orofacial muscle pain condition. The KATP expression in TG and behavioral studies were conducted in age matched male and female Sprague-Dawley rats. RT-PCR experiments showed that the mRNAs for the inwardly rectifying pore-forming subunits, Kir6.1 and Kir6.2, as well as the regulatory sulfonylurea subunits, SUR1 and SUR2, were reliably detected in TG. Subsequent western blot analysis confirmed that proteins for all four subunits are expressed in TG, and showed that Kir6.2 is expressed at a significantly higher level in male TG compared to that of female rats. This observation was confirmed by the immunohistochemical demonstration of higher percentages of Kir6 positive masseter afferents in female rats. Masseteric injection of capsaicin evokes a time dependent increase in masseter sensitivity to noxious mechanical stimulation. A specific KATP agonist, pinacidil, dose-dependently attenuated the capsaicin-induced mechanical hypersensitivity in male rats. The dose of pinacidil (20 μg) that completely blocked the capsaicin responses in male rats was ineffective in female rats regardless of their estrus phases. Only at the highest dose (300 μg) we used, pinacidil was partially effective in female rats. Similarly, another KATP agonist, diazoxide which targets different KATP subunits also showed sex specific responses in attenuating capsaicin-induced masseter hypersensitivity. These data suggested that sex differences in functional KATP expression in TG may underlie sex specific responses to KATP agonists. The present study provided novel information on sex differences in KATP expression in TG and its contribution under an orofacial muscle pain condition.
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Affiliation(s)
- K Niu
- Program in Neuroscience, Department of Neural and Pain Sciences, University of Maryland Baltimore School of Dentistry, 650 West Baltimore Street, Baltimore, MD 21201, USA
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