Professor VICTORIA CHAPMAN's Outputs (30)

Immunomodulation and fibroblast dynamics driving nociceptive joint pain within inflammatory synovium: Unravelling mechanisms for therapeutic advancements in osteoarthritis (2024)
Journal Article
Wijesinghe, S. N., Ditchfield, C., Flynn, S., Agrawal, J., Davis, E. T., Dajas-Bailador, F., Chapman, V., & Jones, S. W. (2024). Immunomodulation and fibroblast dynamics driving nociceptive joint pain within inflammatory synovium: Unravelling mechanisms for therapeutic advancements in osteoarthritis. Osteoarthritis and Cartilage, 32(11), 1358-1370. https://doi.org/10.1016/j.joca.2024.06.011

Objective
Synovitis is a widely accepted sign of osteoarthritis (OA), characterised by tissue hyperplasia, where increased infiltration of immune cells and proliferation of resident fibroblasts adopt a pro-inflammatory phenotype, and increased the p... Read More about Immunomodulation and fibroblast dynamics driving nociceptive joint pain within inflammatory synovium: Unravelling mechanisms for therapeutic advancements in osteoarthritis.

Modelling the role of enzymatic pathways in the metabolism of docosahexaenoic acid by monocytes and its association with osteoarthritic pain (2024)
Journal Article
Franks, S. J., Gowler, P. R., Dunster, J. L., Turnbull, J., Gohir, S. A., Kelly, A., Valdes, A. M., King, J. R., Barrett, D. A., Chapman, V., & Preston, S. (2024). Modelling the role of enzymatic pathways in the metabolism of docosahexaenoic acid by monocytes and its association with osteoarthritic pain. Mathematical Biosciences, 374, Article 109228. https://doi.org/10.1016/j.mbs.2024.109228

Chronic pain is a major cause of disability and suffering in osteoarthritis (OA) patients. Endogenous specialised pro-resolving molecules (SPMs) curtail pro-inflammatory responses. One of the SPM intermediate oxylipins, 17-hydroxydocasahexaenoic acid... Read More about Modelling the role of enzymatic pathways in the metabolism of docosahexaenoic acid by monocytes and its association with osteoarthritic pain.

Serum levels of hydroxylated metabolites of arachidonic acid cross-sectionally and longitudinally predict knee pain progression: an observational cohort study (2024)
Journal Article
Turnbull, J., Jha, R. R., Gowler, P. R., Ferrands-Bentley, R., Kim, D.-H., Barrett, D. A., Sarmanova, A., Fernandes, G. S., Doherty, M., Zhang, W., Walsh, D. A., Valdes, A. M., & Chapman, V. (2024). Serum levels of hydroxylated metabolites of arachidonic acid cross-sectionally and longitudinally predict knee pain progression: an observational cohort study. Osteoarthritis and Cartilage, 32(8), 990-1000. https://doi.org/10.1016/j.joca.2024.04.006

Objective: To examine associations between serum oxylipins, which regulate tissue repair and pain signalling, and knee pain/radiographic osteoarthritis (OA) at baseline and knee pain at 3 year follow-up.

Method: Baseline, and 3 year follow-up, kne... Read More about Serum levels of hydroxylated metabolites of arachidonic acid cross-sectionally and longitudinally predict knee pain progression: an observational cohort study.

The rat Osteoarthritis Bone Score: a new histological system for scoring subchondral pathology in rat knees analogous to histological correlates of human OA bone marrow lesions (2024)
Presentation / Conference Contribution
McWilliams, D. F., Shahtaheri, M., Koushesh, S., Joseph, C., Gowler, P., Chapman, V., …Walsh, D. A. (2024). The rat Osteoarthritis Bone Score: a new histological system for scoring subchondral pathology in rat knees analogous to histological correlates of human OA bone marrow lesions. Osteoarthritis and Cartilage, 32(Supplement 1), S432. https://doi.org/10.1016/j.joca.2024.02.633

Purpose (the aim of the study): Bone marrow lesions (BMLs) are detected by MRI in the in human osteoarthritis (OA) subchondral bone and associated with pain. We previously described 7 histological features associated with BMLs from which we developed... Read More about The rat Osteoarthritis Bone Score: a new histological system for scoring subchondral pathology in rat knees analogous to histological correlates of human OA bone marrow lesions.

Sustained morphine exposure alters spinal NMDA receptor and astrocyte expression and exacerbates chronic pain behavior in female rats (2024)
Journal Article
Gonçalves, S. V., Woodhams, S. G., Li, L., Hathway, G. J., & Chapman, V. (2024). Sustained morphine exposure alters spinal NMDA receptor and astrocyte expression and exacerbates chronic pain behavior in female rats. PAIN Reports, 9(2), Article e1145. https://doi.org/10.1097/pr9.0000000000001145

IntroductionSustained opioid use has long-term negative impacts on future pain experience, particularly in women. This study aimed to investigate the underlying spinal neurobiology of this clinical observation in an experimental model of joint pain.O... Read More about Sustained morphine exposure alters spinal NMDA receptor and astrocyte expression and exacerbates chronic pain behavior in female rats.

Evaluation of cannabidiol nanoparticles and nanoemulsion biodistribution in the central nervous system after intrathecal administration for the treatment of pain (2023)
Journal Article
Muresan, P., Woodhams, S., Smith, F., Taresco, V., Shah, J., Wong, M., …Marlow, M. (2023). Evaluation of cannabidiol nanoparticles and nanoemulsion biodistribution in the central nervous system after intrathecal administration for the treatment of pain. Nanomedicine: Nanotechnology, Biology and Medicine, 49, Article 102664. https://doi.org/10.1016/j.nano.2023.102664

We investigated how the biodistribution of cannabidiol (CBD) within the central nervous system (CNS) is influenced by two different formulations, an oil-in-water (O/W) nanoemulsion and polymer-coated nanoparticles (PCNPs). We observed that both CBD f... Read More about Evaluation of cannabidiol nanoparticles and nanoemulsion biodistribution in the central nervous system after intrathecal administration for the treatment of pain.

Serum Levels of Proinflammatory Lipid Mediators and Specialized Proresolving Molecules Are Increased in Patients With Severe Acute Respiratory Syndrome Coronavirus 2 and Correlate With Markers of the Adaptive Immune Response (2022)
Journal Article
Turnbull, J., Jha, R. R., Ortori, C. A., Lunt, E., Tighe, P. J., Irving, W. L., …Chapman, V. (2022). Serum Levels of Proinflammatory Lipid Mediators and Specialized Proresolving Molecules Are Increased in Patients With Severe Acute Respiratory Syndrome Coronavirus 2 and Correlate With Markers of the Adaptive Immune Response. Journal of Infectious Diseases, 225(12), 2142-2154. https://doi.org/10.1093/infdis/jiab632

BACKGROUND: Specialized proresolution molecules (SPMs) halt the transition to chronic pathogenic inflammation. We aimed to quantify serum levels of pro- and anti-inflammatory bioactive lipids in severe acute respiratory syndrome coronavirus 2 (SARS-C... Read More about Serum Levels of Proinflammatory Lipid Mediators and Specialized Proresolving Molecules Are Increased in Patients With Severe Acute Respiratory Syndrome Coronavirus 2 and Correlate With Markers of the Adaptive Immune Response.

Serum levels of specialised pro-resolving molecule pathways are greatly increased in SARS-CoV-2 patients and correlate with markers of the adaptive immune response (2021)
Preprint / Working Paper
Turnbull, J., Jha, R., Ortori, C. A., Lunt, E., Tighe, P. J., Irving, W. L., Gohir, S. A., Kim, D.-H., Valdes, A. M., Tarr, A. W., Barrett, D. A., & Chapman, V. Serum levels of specialised pro-resolving molecule pathways are greatly increased in SARS-CoV-2 patients and correlate with markers of the adaptive immune response

Background Specialised pro-resolution molecules (SPMs) halt the transition to chronic pathogenic inflammation. We aimed to quantify serum levels of pro- and anti-inflammatory bioactive lipids in SARS-CoV-2 patients, and to identify potential relation... Read More about Serum levels of specialised pro-resolving molecule pathways are greatly increased in SARS-CoV-2 patients and correlate with markers of the adaptive immune response.

The anti-inflammatory effect of bacterial short chain fatty acids is partially mediated by endocannabinoids (2021)
Journal Article
Vijay, A., Kouraki, A., Gohir, S., Turnbull, J., Kelly, A., Chapman, V., …Valdes, A. M. (2021). The anti-inflammatory effect of bacterial short chain fatty acids is partially mediated by endocannabinoids. Gut Microbes, 13(1), Article 1997559. https://doi.org/10.1080/19490976.2021.1997559

The endocannabinoid (EC) system has pleiotropic functions in the body. It plays a key role in energy homeostasis and the development of metabolic disorders being a mediator in the relationship between the gut microbiota and host metabolism. In the cu... Read More about The anti-inflammatory effect of bacterial short chain fatty acids is partially mediated by endocannabinoids.

Neonatal complete Freund's adjuvant-induced inflammation does not induce or alter hyperalgesic priming or alter adult distributions of C-fibre dorsal horn innervation (2020)
Journal Article
Cooper, A. H., Hanmer, J. M., Chapman, V., & Hathway, G. J. (2020). Neonatal complete Freund's adjuvant-induced inflammation does not induce or alter hyperalgesic priming or alter adult distributions of C-fibre dorsal horn innervation. PAIN Reports, 5(6), Article e872. https://doi.org/10.1097/PR9.0000000000000872

Introduction: Inflammation during the neonatal period can exacerbate pain severity following reinjury in adulthood. This is driven by alterations in the postnatal development of spinal and supraspinal nociceptive circuitry. However, the contribution... Read More about Neonatal complete Freund's adjuvant-induced inflammation does not induce or alter hyperalgesic priming or alter adult distributions of C-fibre dorsal horn innervation.

Contribution of nerves within osteochondral channels to osteoarthritis knee pain in humans and rats (2020)
Journal Article
Aso, K., Shahtaheri, S. M., Hill, R., Wilson, D., McWilliams, D. F., Nwosu, L. N., …Walsh, D. A. (2020). Contribution of nerves within osteochondral channels to osteoarthritis knee pain in humans and rats. Osteoarthritis and Cartilage, https://doi.org/10.1016/j.joca.2020.05.010

© 2020 Osteoarthritis Research Society International Objectives: Subchondral bone may contribute to knee osteoarthritis (OA) pain. Nerve growth factor (NGF) can stimulate nerve growth through TrkA. We aimed to identify how sensory nerve growth at the... Read More about Contribution of nerves within osteochondral channels to osteoarthritis knee pain in humans and rats.

Investigating musculoskeletal health and wellbeing; A cohort study protocol (2020)
Journal Article
Millar, B., McWilliams, D. F., Abhishek, A., Akin-Akinyosoye, K., Auer, D. P., Chapman, V., …Walsh, D. A. (2020). Investigating musculoskeletal health and wellbeing; A cohort study protocol. BMC Musculoskeletal Disorders, 21(1), Article 182. https://doi.org/10.1186/s12891-020-03195-4

© 2020 The Author(s). Background: In an ageing population, pain, frailty and disability frequently coexist across a wide range of musculoskeletal diagnoses, but their associations remain incompletely understood. The Investigating Musculoskeletal Heal... Read More about Investigating musculoskeletal health and wellbeing; A cohort study protocol.

Contribution of sensory nerves within osteochondral channels to pain in human and rat knee osteoarthritis (2019)
Journal Article
Aso, K., Shahtaheri, S., Wilson, D., Hill, R., McWilliams, D., Walsh, D., & Chapman, V. (2019). Contribution of sensory nerves within osteochondral channels to pain in human and rat knee osteoarthritis. Osteoarthritis and Cartilage, 27(Supplelement 1), S72. https://doi.org/10.1016/j.joca.2019.02.102

Omega-6 oxylipins generated by soluble epoxide hydrolase are associated with knee osteoarthritis (2018)
Journal Article
Valdes, A. M., Ravipati, S., Pousinis, P., Menni, C., Mangino, M., Abhishek, A., Chapman, V., Barrett, D. A., & Doherty, M. (in press). Omega-6 oxylipins generated by soluble epoxide hydrolase are associated with knee osteoarthritis. Journal of Lipid Research, 59(7), Article jlr.P085118. https://doi.org/10.1194/jlr.P085118

Omega-6 fatty acids are important inflammatory mediators increased in joints with osteoarthritis (OA) joints. To investigate the relationship between omega-6 fatty acids and knee OA 22 omega-6 lipids (arachidonic acid, linoleic acid and 20 oxylipins)... Read More about Omega-6 oxylipins generated by soluble epoxide hydrolase are associated with knee osteoarthritis.

Differential contributions of peripheral and central mechanisms to pain in a rodent model of osteoarthritis (2018)
Journal Article
Haywood, A. R., Hathway, G. J., & Chapman, V. (in press). Differential contributions of peripheral and central mechanisms to pain in a rodent model of osteoarthritis. Scientific Reports, 8, Article 7122. https://doi.org/10.1038/s41598-018-25581-8

The mechanisms underlying the transition from acute nociceptive pain to centrally maintained chronic pain are not clear. We have studied the contributions of the peripheral and central nervous systems during the development of osteoarthritis (OA) pai... Read More about Differential contributions of peripheral and central mechanisms to pain in a rodent model of osteoarthritis.

Therapeutic benefit for late, but not early, passage mesenchymal stem cells on pain behaviour in an animal model of osteoarthritis (2017)
Journal Article
Chapman, V., Markides, H., Sagar, D. R., Xu, L., Burston, J. J., Mapp, P., …El Haj, A. J. (2017). Therapeutic benefit for late, but not early, passage mesenchymal stem cells on pain behaviour in an animal model of osteoarthritis. Stem Cells International, 2017, https://doi.org/10.1155/2017/2905104

Background: Mesenchymal stem cells (MSCs) have a therapeutic potential for the treatment of osteoarthritic (OA) joint pathology and pain. The aims of this study were to determine the influence of a passage number on the effects of MSCs on pain behavi... Read More about Therapeutic benefit for late, but not early, passage mesenchymal stem cells on pain behaviour in an animal model of osteoarthritis.

Association of the resolvin precursor 17-HDHA, but not D- or E- series resolvins, with heat pain sensitivity and osteoarthritis pain in humans (2017)
Journal Article
Valdes, A. M., Ravipati, S., Menni, C., Abhishek, A., Metrustry, S., Harris, J., Nessa, A., Williams, F. M., Spector, T. D., Doherty, M., Chapman, V., & Barrett, D. A. (in press). Association of the resolvin precursor 17-HDHA, but not D- or E- series resolvins, with heat pain sensitivity and osteoarthritis pain in humans. Scientific Reports, 7, Article 10748. https://doi.org/10.1038/s41598-017-09516-3

Resolvins are omega-3 fatty acid derived potent bioactive lipids that resolve inflammation and modulate transient receptor potential channels. Exogenous administration of the resolvin precursor 17-HDHA shows a strong analgesic effect in animal models... Read More about Association of the resolvin precursor 17-HDHA, but not D- or E- series resolvins, with heat pain sensitivity and osteoarthritis pain in humans.

Pain prediction by serum biomarkers of bone turnover in people with knee osteoarthritis: an observational study of TRAcP5b and cathepsin K in OA (2017)
Journal Article
Nwosu, L. N., Allen, M., Wyatt, L., Huebner, J., Chapman, V., Walsh, D. A., & Kraus, V. (2017). Pain prediction by serum biomarkers of bone turnover in people with knee osteoarthritis: an observational study of TRAcP5b and cathepsin K in OA. Osteoarthritis and Cartilage, 25(6), https://doi.org/10.1016/j.joca.2017.01.002

Objectives: To investigate serum biomarkers, tartrate resistant acid phosphatase 5b (TRAcP5b) and cathepsin K, indicative of osteoclastic bone resorption, and their relationship to pain and pain change in knee osteoarthritis (OA).
Methods: Sera and... Read More about Pain prediction by serum biomarkers of bone turnover in people with knee osteoarthritis: an observational study of TRAcP5b and cathepsin K in OA.

Inhibitory effects of aspirin-triggered resolvin D1 on spinal nociceptive processing in rat pain models (2016)
Journal Article
Meesawatsom, P., Burston, J., Hathway, G., Bennett, A., & Chapman, V. (2016). Inhibitory effects of aspirin-triggered resolvin D1 on spinal nociceptive processing in rat pain models. Journal of Neuroinflammation, 13, Article 233. https://doi.org/10.1186/s12974-016-0676-6

Background: Harnessing the actions of the resolvin pathways has the potential for the treatment of a wide range of conditions associated with overt inflammatory signalling. Aspirin-triggered resolvin D1 (AT-RvD1) has robust analgesic effects in behav... Read More about Inhibitory effects of aspirin-triggered resolvin D1 on spinal nociceptive processing in rat pain models.

Robust anti-nociceptive effects of MAG lipase inhibition in a model of osteoarthritis pain (2016)
Journal Article
Burston, J. J., Mapp, P. I., Sarmad, S., Barrett, D. A., Niphakis, M. J., Cravatt, B. F., Walsh, D. A., & Chapman, V. (2016). Robust anti-nociceptive effects of MAG lipase inhibition in a model of osteoarthritis pain. British Journal of Pharmacology, 173(21), 3134-3144. https://doi.org/10.1111/bph.13574

BACKGROUND AND PURPOSE: Chronic pain is often a symptom of knee osteoarthritis (OA) for which current analgesics are either inadequate, or are associated with serious side effects. The endocannabinoid system may offer alternative targets for pain-rel... Read More about Robust anti-nociceptive effects of MAG lipase inhibition in a model of osteoarthritis pain.

Anti-nociceptive and desensitizing effects of olvanil on capsaicin-induced thermal hyperalgesia in the rat (2016)
Journal Article
Alsalem, M., Millns, P., Altarifi, A., El-Salem, K., Chapman, V., & Kendall, D. A. (in press). Anti-nociceptive and desensitizing effects of olvanil on capsaicin-induced thermal hyperalgesia in the rat. BMC Pharmacology and Toxicology, 17, https://doi.org/10.1186/s40360-016-0074-9

Background: Olvanil (NE 19550) is a non-pungent synthetic analogue of capsaicin, the natural pungent ingredient of capsicum which activates the transient receptor potential vanilloid type-1 (TRPV1) channel and was developed as a potential analgesic c... Read More about Anti-nociceptive and desensitizing effects of olvanil on capsaicin-induced thermal hyperalgesia in the rat.

Relationship between structural pathology and pain behaviour in a model of osteoarthritis (OA) (2016)
Journal Article
Nwosu, L. N., Mapp, P. I., Chapman, V., & Walsh, D. A. (2016). Relationship between structural pathology and pain behaviour in a model of osteoarthritis (OA). Osteoarthritis and Cartilage, 24(11), 1910-1917. https://doi.org/10.1016/j.joca.2016.06.012

Objectives
To address the hypothesis that different types of established OA pain behaviours have associations with different aspects of articular pathology, we investigated the relationship between structural knee joint pathology and pain behaviour... Read More about Relationship between structural pathology and pain behaviour in a model of osteoarthritis (OA).

Neuron-immune mechanisms contribute to pain in early stages of arthritis (2016)
Journal Article
Nieto, F. R., Clark, A. K., Grist, J., Hathway, G. J., Chapman, V., & Malcangio, M. (2016). Neuron-immune mechanisms contribute to pain in early stages of arthritis. Journal of Neuroinflammation, 13, https://doi.org/10.1186/s12974-016-0556-0

Background: Rheumatoid arthritis (RA) patients frequently show weak correlations between the magnitude of pain and inflammation suggesting that mechanisms other than overt peripheral inflammation contribute to pain in RA. We assessed changes in micro... Read More about Neuron-immune mechanisms contribute to pain in early stages of arthritis.

Neural correlates of hyperalgesia in the monosodium iodoacetate model of osteoarthritis pain (2016)
Journal Article
Abaei, M., Sagar, D. R., Stockley, E. G., Spicer, C. H., Prior, M., Chapman, V., & Auer, D. P. (in press). Neural correlates of hyperalgesia in the monosodium iodoacetate model of osteoarthritis pain. Molecular Pain, 12, https://doi.org/10.1177/1744806916642445

Background: The mechanisms driving osteoarthritic pain remain poorly understood, but there is increasing evidence for a role of the central nervous system in the chronification of pain.We used functional magnetic resonance imaging to investigate the... Read More about Neural correlates of hyperalgesia in the monosodium iodoacetate model of osteoarthritis pain.

Blocking the tropomyosin receptor kinase A (TrkA) receptor inhibits pain behaviour in two rat models of osteoarthritis (2015)
Journal Article
Nwosu, L. N., Mapp, P. I., Chapman, V., & Walsh, D. A. (in press). Blocking the tropomyosin receptor kinase A (TrkA) receptor inhibits pain behaviour in two rat models of osteoarthritis. Annals of the Rheumatic Diseases, 75(6), https://doi.org/10.1136/annrheumdis-2014-207203

Objectives: Tropomyosin receptor kinase A (TrkA) mediates nociceptor sensitisation by nerve growth factor (NGF), but it is unknown whether selective TrkA inhibition will be an effective strategy for treating osteoarthritis (OA) pain. We determined th... Read More about Blocking the tropomyosin receptor kinase A (TrkA) receptor inhibits pain behaviour in two rat models of osteoarthritis.

Effects of pro-inflammatory cytokines on cannabinoid CB1 and CB2 receptors in immune cells (2015)
Journal Article
Jean-Gilles, L., Braitch, M., Latif, M. L., Aram, J., Fahey, A. J., Edwards, L. J., …Constantinescu, C. S. (2015). Effects of pro-inflammatory cytokines on cannabinoid CB1 and CB2 receptors in immune cells. Acta Physiologica, 214(1), 63-74. https://doi.org/10.1111/apha.12474

© 2015 The Authors. Aims: To investigate the regulation of cannabinoid receptors CB1 and CB2 on immune cells by pro-inflammatory cytokines and its potential relevance to the inflammatory neurological disease, multiple sclerosis (MS). CB1 and CB2 sign... Read More about Effects of pro-inflammatory cytokines on cannabinoid CB1 and CB2 receptors in immune cells.

Calcitonin gene-related peptide-expressing sensory neurons and spinal microglial reactivity contribute to pain states in collagen-induced arthritis (2015)
Journal Article
Nieto, F. R., Clark, A. K., Grist, J., Chapman, V., & Malcangio, M. (2015). Calcitonin gene-related peptide-expressing sensory neurons and spinal microglial reactivity contribute to pain states in collagen-induced arthritis. Arthritis and Rheumatology, 67(6), https://doi.org/10.1002/art.39082

Objective

To evaluate the contribution of sensory neurons in ankle joints and adjacent tissue to the development of pain in collagen‐induced arthritis (CIA), and to determine the relationship between pain and the appearance of clinical signs.... Read More about Calcitonin gene-related peptide-expressing sensory neurons and spinal microglial reactivity contribute to pain states in collagen-induced arthritis.

Dissecting the contribution of knee joint NGF to spinal nociceptive sensitization in a model of OA pain in the rat (2015)
Journal Article
Sagar, D. R., Nwosu, L. N., Walsh, D. A., & Chapman, V. (2015). Dissecting the contribution of knee joint NGF to spinal nociceptive sensitization in a model of OA pain in the rat. Osteoarthritis and Cartilage, 23(6), https://doi.org/10.1016/j.joca.2015.01.010

Objective: Although analgesic approaches targeting nerve growth factor (NGF) for the treatment of osteoarthritis (OA) pain remain of clinical interest, neurophysiological mechanisms by which NGF contribute to OA pain remain unclear. We investigated t... Read More about Dissecting the contribution of knee joint NGF to spinal nociceptive sensitization in a model of OA pain in the rat.

Simultaneous tissue profiling of eicosanoid and endocannabinoid lipid families in a rat model of osteoarthritis (2014)
Journal Article

We describe a novel LC method for the simultaneous and quantitative profiling of 43 oxylipins including eicosanoids, endocannabinoids, and structurally related bioactive lipids with modified acyl groups. The LC-MS/MS method uses switching at a define... Read More about Simultaneous tissue profiling of eicosanoid and endocannabinoid lipid families in a rat model of osteoarthritis.

Tonic modulation of spinal hyperexcitability by the endocannabinoid receptor system in a rat model of osteoarthritis pain (2010)
Journal Article
Sagar, D. R., Staniaszek, L. E., Okine, B. N., Woodhams, S., Norris, L. M., Pearson, R. G., …Chapman, V. (2010). Tonic modulation of spinal hyperexcitability by the endocannabinoid receptor system in a rat model of osteoarthritis pain. Arthritis and Rheumatism, 62(12), https://doi.org/10.1002/art.27698

Objective. To investigate the impact of an experimental
model of osteoarthritis (OA) on spinal nociceptive
processing and the role of the inhibitory endocannabinoid
system in regulating sensory processing at the
spinal level.
Methods. Experiment... Read More about Tonic modulation of spinal hyperexcitability by the endocannabinoid receptor system in a rat model of osteoarthritis pain.