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Harlow BL, Coleman CM, Mühlrad H, Yan J, Linnros E, Lu D, Fox MP, Bohm-Starke N. The Association Between Immune-Related Conditions Across the Life-Course and Provoked Vulvodynia. THE JOURNAL OF PAIN 2023; 24:1415-1422. [PMID: 36940787 PMCID: PMC10440273 DOI: 10.1016/j.jpain.2023.03.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 03/07/2023] [Accepted: 03/11/2023] [Indexed: 03/23/2023]
Abstract
Vulvodynia, impacts up to 8% of women by age 40, and is hypothesized to manifest through an altered immune-inflammatory response. To test this hypothesis, we identified all women born in Sweden between 1973 and 1996 diagnosed with localized provoked vulvodynia (N76.3) and/or vaginismus (N94.2 or F52.5) between 2001 and 2018. We matched each case to two women from the same birth year with no vulvar pain ICD codes. As a proxy for immune dysfunction, we used Swedish Registry data to capture 1) immunodeficiencies, 2) single organ and multiorgan autoimmune conditions, 3) allergy and atopies, and 4) malignancies involving immune cells across the life course. Women with vulvodynia, vaginismus or both were more likely to experience immune deficiencies (OR 1.8, 95% CI, 1.2-2.8), single organ (OR 1.4, 95% CI, 1.2-1.6) and/or multi-organ (OR 1.6, 95% CI, 1.3-1.9) immune disorders, and allergy/atopy conditions (OR 1.7, 95% CI, 1.6-1.8) compared to controls. We observed greater risk with increasing numbers of unique immune related conditions (1 code: OR = 1.6, 95% CI, 1.5-1.7; 2 codes: OR = 2.4, 95% CI, 2.1-2.9; 3 or more codes: OR = 2.9, 1.6-5.4). These findings suggest that women with vulvodynia may have a more compromised immune system either at birth or at points across the life course than women with no vulvar pain history. PERSPECTIVE: Women with vulvodynia are substantially more likely to experience a spectrum of immune related conditions across the life course. These findings lend support to the hypothesis that chronic inflammation initiates the hyperinnervation that causes the debilitating pain in women with vulvodynia.
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Affiliation(s)
- Bernard L Harlow
- Department of Epidemiology, Boston University School of Public Health. Boston, Massachusetts.
| | - Chad M Coleman
- Department of Epidemiology, Boston University School of Public Health. Boston, Massachusetts
| | - Hanna Mühlrad
- Department of Clinical Sciences, Division of Obstetrics and Gynecology, Karolinska Institutet, Danderyd Hospital, Stockholm, Sweden; The Institute for Evaluation of Labor Market and Education Policy (IFAU), Uppsala, Sweden
| | - Jacinth Yan
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Evelina Linnros
- Institute for International Economic Studies, Stockholm University, Stockholm, Sweden
| | - Donghao Lu
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Matthew P Fox
- Department of Epidemiology, Boston University School of Public Health. Boston, Massachusetts; Department of Global Health, Boston University School of Public Health, Boston, Massachusetts
| | - Nina Bohm-Starke
- Department of Clinical Sciences, Division of Obstetrics and Gynecology, Karolinska Institutet, Danderyd Hospital, Stockholm, Sweden
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Awad-Igbaria Y, Dadon S, Shamir A, Livoff A, Shlapobersky M, Bornstein J, Palzur E. Characterization of Early Inflammatory Events Leading to Provoked Vulvodynia Development in Rats. J Inflamm Res 2022; 15:3901-3923. [PMID: 35845089 PMCID: PMC9286136 DOI: 10.2147/jir.s367193] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 06/16/2022] [Indexed: 11/23/2022] Open
Abstract
Background Provoked vulvodynia (PV) is the main cause of vulvar pain and dyspareunia. The etiology of PV has not yet been elucidated. However, PV is associated with a history of recurrent inflammation, and its often accompanied by increases in the numbers of mast cells (MCs) and sensory hyperinnervation in the vulva. Therefore, this study aimed to examine the role of MCs and the early inflammatory events in the development of chronic vulvar pain in a rat model of PV. Methods Mechanical and thermal vulvar sensitivity was measured for 5 months following zymosan vulvar challenges. Vulvar changes in glutamate and nerve growth factor (NGF) were analyzed using ELISA. Immunofluorescence (IF) staining of the vulvar section after 20, 81, and 160 days of the zymosan challenge were performed to test MCs accumulation, hyperinnervation, and expression of pain channels (transient receptor potential vanilloid/ankyrin-1-TRPV1 & TRPA1) in vulvar neurons. Changes in the development of vulvar pain were evaluated following the administration of the MCs stabilizer ketotifen fumarate (KF) during zymosan vulvar challenges. Results Zymosan-challenged rats developed significant mechanical and thermal vulvar sensitivity that persisted for over 160 days after the zymosan challenge. During inflammation, increased local concentrations of NGF and glutamate and a robust increase in MCs degranulation were observed in zymosan-challenged rats. In addition, zymosan-challenged rats displayed sensory hyperinnervation and an increase in the expression of TRPV1 and TRPA1. Treatment with KF attenuated the upregulated level of NGF during inflammation, modulated the neuronal modifications, reduced MCs accumulation, and enhanced mechanical hypersensitivity after repeated inflammation challenges. Conclusion The present findings suggest that vulvar hypersensitivity is mediated by MCs accumulation, nerve growth, and neuromodulation of TRPV1 and TRPA1. Hence, KF treatment during the critical period of inflammation contributes to preventing chronic vulvar pain development.
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Affiliation(s)
- Yaseen Awad-Igbaria
- Faculty of Medicine in the Galilee, Bar-Ilan University, Safed, Israel.,The Research Institute of Galilee Medical Center, Nahariya, Israel
| | - Shilo Dadon
- Faculty of Medicine in the Galilee, Bar-Ilan University, Safed, Israel.,The Research Institute of Galilee Medical Center, Nahariya, Israel
| | - Alon Shamir
- Psychobiology Research Laboratory, Mazor Mental Health Center, Akko, Israel.,The Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Alejandro Livoff
- Pathology Department, Barzilai University Medical Center, Ashkelon, Israel
| | - Mark Shlapobersky
- Pathology Department, Barzilai University Medical Center, Ashkelon, Israel
| | - Jacob Bornstein
- Faculty of Medicine in the Galilee, Bar-Ilan University, Safed, Israel.,The Research Institute of Galilee Medical Center, Nahariya, Israel
| | - Eilam Palzur
- The Research Institute of Galilee Medical Center, Nahariya, Israel
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Dorff SR, Afrin LB. Mast cell activation syndrome in pregnancy, delivery, postpartum and lactation: a narrative review. J OBSTET GYNAECOL 2020; 40:889-901. [PMID: 32148151 DOI: 10.1080/01443615.2019.1674259] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Mast cell activation syndrome (MCAS) is a chronic multisystem disease of aberrant constitutive and reactive mast cell mediator release causing generally inflammatory, allergic, and dystrophic issues. The pathobiology of MCAS drives extraordinary clinical complexity and heterogeneity, which led to only recent recognition despite increasingly apparent substantial prevalence, perhaps as high as 17%. It also has a strong female predilection. Thus, MCAS inescapably impacts pregnancy and the post-partum period in many women. No specific research in the pregnant or post-partum MCAS population has been performed yet. However, its prevalence and potential for driving substantial morbidity merit obstetric providers' acquaintance with this illness and its potential impacts on their patients during pregnancy, delivery, the post-partum period, and lactation. Extensive literature review across all medical specialities, plus direct experience in the authors' practices, provides guidance in recognising MCAS in pregnancy and diagnosing and effectively managing it. Described herein are manners in which MCAS, a protean multisystem disease, adversely affects all stages of pregnancy and post-partum. In order to reduce risks of MCAS causing complications before, during and after pregnancy, identifying and controlling the syndrome prior to pregnancy is best, but, even if the disease is not recognised until late, there may still be opportunities to mitigate its effects. There is precedent for improved outcomes if comorbid MCAS is recognised and controlled. This review provides the first comprehensive guide for obstetric providers regarding this emerging major comorbidity.
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Trutnovsky G, Plieseis C, Bjelic-Radisic V, BertholinyGalvez MC, Tamussino K, Ulrich D. Vulvodynia and chronic pelvic pain in a gynecologic outpatient clinic. J Psychosom Obstet Gynaecol 2019; 40:243-247. [PMID: 29848143 DOI: 10.1080/0167482x.2018.1477753] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
Abstract
Introduction: Vulvodynia and chronic pelvic pain are common but underdiagnosed chronic gynecologic pain syndromes. Insufficient knowledge regarding prevalence, typical pain patterns and associated factors contribute to delayed diagnosis. The present study explored the symptoms and characteristics of women presenting with vulvodynia and/or chronic pelvic pain to a gynecologic outpatient clinic. Materials and methods: Electronic charts of women diagnosed with vulvodynia and/or chronic pelvic pain between January 2010 and December 2015 were reviewed. Type of pain, duration of symptoms, previous medical assessments and therapies, comorbidities and patient characteristics were analyzed with descriptive statistics. Results: One hundred and twenty-seven women (mean age 36, range 18-75 years) met the diagnostic criteria for chronic gynecologic pain syndromes. Sixty-five women were diagnosed with CPP only, 42 with vulvodynia and 20 with both conditions. Endometriosis was suspected or diagnosed in 35 (54%) women with CPP. History of pain ranged from 3 months to 20 years. Comorbidities were common, with 40% of women being diagnosed with depression or other mood disorders, 15% with urological and 9% with gastrointestinal conditions. Conclusions: There is a need for increased awareness regarding vulvodynia and CPP among health care providers. A comprehensive history is important for adequate diagnosis.
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Affiliation(s)
- Gerda Trutnovsky
- a Obstetrics and Gynecogy , Medizinische Universitat Graz , Graz , Austria
| | - Christina Plieseis
- a Obstetrics and Gynecogy , Medizinische Universitat Graz , Graz , Austria
| | | | | | - Karl Tamussino
- a Obstetrics and Gynecogy , Medizinische Universitat Graz , Graz , Austria
| | - Daniela Ulrich
- a Obstetrics and Gynecogy , Medizinische Universitat Graz , Graz , Austria
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Bautrant E, Porta O, Murina F, Mühlrad H, Levêque C, Riant T, Ploteau S, Valancogne G, Levesque A. Provoked vulvar vestibulodynia: Epidemiology in Europe, physio-pathology, consensus for first-line treatment and evaluation of second-line treatments. J Gynecol Obstet Hum Reprod 2019; 48:685-688. [PMID: 31051298 DOI: 10.1016/j.jogoh.2019.04.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Accepted: 04/26/2019] [Indexed: 10/26/2022]
Affiliation(s)
- Eric Bautrant
- Pelvi-Perineal Surgery and Rehabilitation Department, Private Medical Center "L'Avancée-Clinique Axium", 44 Avenue du Marechal Lattre de Tassigny, 13090 Aix en Provence, France.
| | - Oriol Porta
- Section Gynecology, Santa Creu i Sant Pau Hospital, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Filippo Murina
- Lower Genital Tract Disease Unit, Obstetrics and Gynecology Department, V Buzzi Hospital, University of Milan, Milan, Italy
| | - Hanna Mühlrad
- Department of Economics, Lund University, 22100, Lund, Sweden
| | - Christine Levêque
- Pelvi-Perineal Surgery and Rehabilitation Department, Private Medical Center "L'Avancée-Clinique Axium", 44 Avenue du Marechal Lattre de Tassigny, 13090 Aix en Provence, France
| | - Thibaut Riant
- "Catherine de Sienne Centre", 2 rue Eric Tabarly, 44202, Nantes, France
| | - Stephane Ploteau
- Federative pelvi-perineology centre, University Hospital of Nantes, 44093, Nantes, France
| | - Guy Valancogne
- "Tête d'or" Reeducation Centre, 85 Boulevard des Belges, 69006, Lyon, France
| | - Amélie Levesque
- Federative pelvi-perineology centre, University Hospital of Nantes, 44093, Nantes, France
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Nerve Growth Factor and Selected Cytokines in Women With and Without Vulvodynia. J Low Genit Tract Dis 2018; 22:139-146. [DOI: 10.1097/lgt.0000000000000377] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Diagnosis and management of vulvodynia in postmenopausal women. Maturitas 2018; 108:84-94. [DOI: 10.1016/j.maturitas.2017.11.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2017] [Revised: 10/25/2017] [Accepted: 11/01/2017] [Indexed: 11/23/2022]
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9
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Repeated hapten exposure induces persistent tactile sensitivity in mice modeling localized provoked vulvodynia. PLoS One 2017; 12:e0169672. [PMID: 28158195 PMCID: PMC5291437 DOI: 10.1371/journal.pone.0169672] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 12/20/2016] [Indexed: 02/06/2023] Open
Abstract
Background Vulvodynia is a remarkably prevalent chronic pain condition of unknown etiology. Epidemiologic studies associate the risk of vulvodynia with a history of atopic disease. We used an established model of hapten-driven contact hypersensitivity to investigate the underlying mechanisms of allergy-provoked prolonged sensitivity to pressure. Methods We sensitized female ND4 Swiss mice to the hapten oxazolone on their flanks, and subsequently challenged them four days later with oxazolone or vehicle for ten consecutive days on the labia. We evaluated labiar sensitivity to touch, local mast cell accumulation, and hyperinnervation after ten challenges. Results Oxazolone-challenged mice developed significant tactile sensitivity that persisted for over three weeks after labiar allergen exposures ceased. Allergic sites were characterized by mast cell accumulation, sensory hyper-innervation and infiltration of regulatory CD4+CD25+FoxP3+ T cells as well as localized early increases in transcripts encoding Nerve Growth Factor and nerve-mast cell synapse marker Cell Adhesion Molecule 1. Local depletion of mast cells by intra-labiar administration of secretagogue compound 48/80 led to a reduction in both nerve density and tactile sensitivity. Conclusions Mast cells regulate allergy-provoked persistent sensitivity to touch. Mast cell-targeted therapeutic strategies may provide novel means to manage and limit chronic pain conditions associated with atopic disease.
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Regauer S, Gamper M, Fehr MK, Viereck V. Sensory Hyperinnervation Distinguishes Bladder Pain Syndrome/Interstitial Cystitis from Overactive Bladder Syndrome. J Urol 2016; 197:159-166. [PMID: 27378135 DOI: 10.1016/j.juro.2016.06.089] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/26/2016] [Indexed: 12/17/2022]
Abstract
PURPOSE Pain is the key symptom that distinguishes bladder pain syndrome/interstitial cystitis from overactive bladder syndrome but overlap occurs. To find a discriminating marker for these bladder diseases we examined sensory hyperinnervation and neurotrophin receptor expression in bladder biopsies as well as nerve growth factor levels in urine. MATERIALS AND METHODS Bladder biopsies from patients with bladder pain syndrome/interstitial cystitis, including 12 with and 19 without Hunner lesions, 13 with overactive bladder syndrome and 12 healthy controls, were analyzed by immunohistochemistry with antibodies to the nerve cell marker PGP9.5 (neuron-specific protein gene product 9.5), p75NTR (p75 neurotrophin receptor), the B-lymphocyte marker CD20 and mast cell tryptase. Urinary nerve growth factor was quantified by enzyme-linked immunosorbent assay. RESULTS Subepithelial sensory hyperinnervation on PGP9.5 staining had 97% sensitivity and 76% specificity, increased lymphocytic infiltration had 90% sensitivity and 80% specificity, and urothelial defects had 97% sensitivity and 76% specificity to distinguish bladder pain syndrome/interstitial cystitis with and without Hunner lesions from overactive bladder syndrome and healthy controls. Increased sensory innervation was associated with submucosal mast cell localization. Staining of p75NTR in basal urothelial cells was indicative of bladder pain syndrome/interstitial cystitis. Urinary nerve growth factor levels were below the detection level and did not differentiate bladder diseases from healthy controls. CONCLUSIONS Sensory hyperinnervation and basal urothelial p75NTR staining together with assessment of inflammatory lymphocytes and urothelial integrity allow for the differentiation of bladder pain syndrome/interstitial cystitis and overactive bladder syndrome even in the absence of Hunner lesions. Furthermore, these histopathological criteria enable the identification of early disease stages or oligosymptomatic/asymptomatic cases and may permit timely treatment to prevent disease progress.
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Affiliation(s)
- Sigrid Regauer
- Department of Gynecology and Obstetrics, Cantonal Hospital Frauenfeld, Frauenfeld, Switzerland; Institute of Pathology, Medical University Graz (SR), Graz, Austria
| | - Marianne Gamper
- Department of Gynecology and Obstetrics, Cantonal Hospital Frauenfeld, Frauenfeld, Switzerland; Institute of Pathology, Medical University Graz (SR), Graz, Austria.
| | - Mathias K Fehr
- Department of Gynecology and Obstetrics, Cantonal Hospital Frauenfeld, Frauenfeld, Switzerland; Institute of Pathology, Medical University Graz (SR), Graz, Austria
| | - Volker Viereck
- Department of Gynecology and Obstetrics, Cantonal Hospital Frauenfeld, Frauenfeld, Switzerland; Institute of Pathology, Medical University Graz (SR), Graz, Austria
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Papoutsis D, Haefner HK, Crum CP, Opipari AW, Reed BD. Vestibular Mast Cell Density in Vulvodynia: A Case-Controlled Study. J Low Genit Tract Dis 2016; 20:275-9. [PMID: 27224531 PMCID: PMC4920700 DOI: 10.1097/lgt.0000000000000221] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES To identify whether mast cell densities in vulvar biopsies from the vestibule are associated with vulvodynia. METHODS We enrolled 100 women aged 19 to 59 years with confirmed vulvodynia cases, 100 racially matched controls, and 100 black control women. All had vulvar biopsies performed at the 7 o'clock position of the vestibule, which were then immunostained to detect c-KIT protein. The numbers of c-KIT positive mast cells per ×400 magnification field were manually counted, and t tests and logistic regression were used to assess the association with case-control status. RESULTS Of the biopsies, 235 were adequate samples for c-KIT testing for mast cells. The mast cell density was substantially lower in black control women (13.9 ± 10.9) in comparison to white control women (22.5 ± 13.2 p < 0.001): hence the analysis was confined to white cases and racially matched control women. Compared with racially matched controls, cases were younger, more likely to be married, and reported a higher household income. The average number of mast cells per ×400 magnification field overall was 19.1 ± 13.2 (range, 0-62). There was no difference in the mast cell count between racially matched cases (22.4 ± 13.9 per ×400 field) and controls (22.5 ± 13.2) in either the univariate or multivariable analyses. Within the group of cases, there was no difference in mast cell density based on the presence or absence of a variety of urogenital symptoms. CONCLUSIONS No difference in mast cell density in biopsies of the vestibule was found between white cases and racially matched controls. Black control women have a lower mast cell density compared with white control women.
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Affiliation(s)
- Dimitrios Papoutsis
- 1Department of Obstetrics and Gynaecology, Shrewsbury and Telford Hospitals NHS Trust, Shrewsbury, UK.; 2Center for Vulvar Diseases, Department of Obstetrics and Gynecology, University of Michigan Health System, Ann Arbor, MI, USA; 3Department of Pathology, Harvard Medical School, Brigham and Women's Hospital, Boston, MA, USA; and 4Department of Family Medicine, University of Michigan Health System, Ann Arbor, MI, USA
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Regauer S. Mast cell activation syndrome in pain syndromes bladder pain syndrome/interstitial cystitis and vulvodynia. Transl Androl Urol 2016; 5:396-7. [PMID: 27297031 PMCID: PMC4893522 DOI: 10.21037/tau.2016.03.12] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Sigrid Regauer
- Department of Pathology, Medical University Graz, Graz, Austria
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Ciszek BP, O'Buckley SC, Nackley. AG. Persistent Catechol-O-methyltransferase-dependent Pain Is Initiated by Peripheral β-Adrenergic Receptors. Anesthesiology 2016; 124:1122-35. [PMID: 26950706 PMCID: PMC5015695 DOI: 10.1097/aln.0000000000001070] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Patients with chronic pain disorders exhibit increased levels of catecholamines alongside diminished activity of catechol-O-methyltransferase (COMT), an enzyme that metabolizes catecholamines. The authors found that acute pharmacologic inhibition of COMT in rodents produces hypersensitivity to mechanical and thermal stimuli via β-adrenergic receptor (βAR) activation. The contribution of distinct βAR populations to the development of persistent pain linked to abnormalities in catecholamine signaling requires further investigation. METHODS Here, the authors sought to determine the contribution of peripheral, spinal, and supraspinal βARs to persistent COMT-dependent pain. They implanted osmotic pumps to deliver the COMT inhibitor OR486 (Tocris, USA) for 2 weeks. Behavioral responses to mechanical and thermal stimuli were evaluated before and every other day after pump implantation. The site of action was evaluated in adrenalectomized rats receiving sustained OR486 or in intact rats receiving sustained βAR antagonists peripherally, spinally, or supraspinally alongside OR486. RESULTS The authors found that male (N = 6) and female (N = 6) rats receiving sustained OR486 exhibited decreased paw withdrawal thresholds (control 5.74 ± 0.24 vs. OR486 1.54 ± 0.08, mean ± SEM) and increased paw withdrawal frequency to mechanical stimuli (control 4.80 ± 0.22 vs. OR486 8.10 ± 0.13) and decreased paw withdrawal latency to thermal heat (control 9.69 ± 0.23 vs. OR486 5.91 ± 0.11). In contrast, adrenalectomized rats (N = 12) failed to develop OR486-induced hypersensitivity. Furthermore, peripheral (N = 9), but not spinal (N = 4) or supraspinal (N = 4), administration of the nonselective βAR antagonist propranolol, the β2AR antagonist ICI-118,511, or the β3AR antagonist SR59230A blocked the development of OR486-induced hypersensitivity. CONCLUSIONS Peripheral adrenergic input is necessary for the development of persistent COMT-dependent pain, and peripherally-acting βAR antagonists may benefit chronic pain patients.
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Affiliation(s)
- Brittney P. Ciszek
- Center for Pain Research and Innovation, Koury Oral Health Sciences Building, University of North Carolina, Chapel Hill NC 27599-7455
| | - Sandra C. O'Buckley
- Center for Pain Research and Innovation, Koury Oral Health Sciences Building, University of North Carolina, Chapel Hill NC 27599-7455
| | - Andrea G. Nackley.
- Center for Pain Research and Innovation, Koury Oral Health Sciences Building, University of North Carolina, Chapel Hill NC 27599-7455
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