ArticleEuropean journal of pain (London, England)2014
Sex differences in μ-opioid receptor expression in trigeminal ganglia under a myositis condition in rats.
Article in European journal of pain (London, England), 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 26 papers.
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Who cites it
26 citing papers in PubMed, 46 citations in OpenAlex.
- Effects of intramuscular morphine in men and women with temporomandibular disorder with myofascial pain.Oral diseases · 2018Trial
- Sex-related pharmacokinetic and pharmacological responses to 4F-furanylfentanyl.Frontiers in pharmacology · 2026Article
- μ-Opioid Receptor Dynamics in the Parameningeal Tissue During Migraine Attacks.Annals of neurology · 2025Article
- Migraine in men.The journal of headache and pain · 2025Review
- The role of gonadal hormones in regulating opioid antinociception.Annals of medicine · 2024Review
- Epigenetic and sex differences in opioid use disorder in chronic pain: A real-world study linked with OPRM1 DNA methylation.Addiction biology · 2024Article
- Modulatory Processes in Craniofacial Pain States.Advances in neurobiology · 2024Article
- Forced swim stress exacerbates inflammation-induced hyperalgesia and oxidative stress in the rat trigeminal ganglia.Frontiers in pain research (Lausanne, Switzerland) · 2024Article
- Solid-Phase Synthesis of the Bicyclic Peptide OL-CTOP Containing Two Disulfide Bridges, and an Assessment of Its In Vivo μ-Opioid Receptor Antagonism after Nasal Administration.Molecules (Basel, Switzerland) · 2023Article
- Intraganglionic reactive oxygen species mediate inflammatory pain and hyperalgesia through TRPA1 in the rat.Frontiers in pain research (Lausanne, Switzerland) · 2023Article
- Sex differences in opioid receptor mediated effects: Role of androgens.Neuroscience and biobehavioral reviews · 2022Review
- Stem Cells from Human Exfoliated Deciduous Teeth Attenuate Trigeminal Neuralgia in Rats.Stem cells international · 2021Article
- Peripherally Acting Opioids in Orofacial Pain.Frontiers in neuroscience · 2021Review
- Article
- Sex differences and mechanisms of muscle pain.Current opinion in physiology · 2019Article
- Testosterone modulation of ethanol effects on the µ-opioid receptor kinetics in castrated rats.Biomedical reports · 2019Article
- Granulocyte-Colony Stimulating Factor-Induced Neutrophil Recruitment Provides Opioid-Mediated Endogenous Anti-nociception in Female Mice With Oral Squamous Cell Carcinoma.Frontiers in molecular neuroscience · 2019Article
- Diffuse noxious inhibitory controls and brain networks are modulated in a testosterone-dependent manner in Sprague Dawley rats.Behavioural brain research · 2018Article
- Neonatal Handling Produces Sex Hormone-Dependent Resilience to Stress-Induced Muscle Hyperalgesia in Rats.The journal of pain · 2018Article
- Effect of Testosterone on TRPV1 Expression in a Model of Orofacial Myositis Pain in the Rat.Journal of molecular neuroscience : MN · 2018Article
Corrections and comments
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Authors and funding
8 authors at 2 institutions in 2 countries.
Funding
Abstract
backgroundPeripheral 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.
methodsMOR 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.
resultsCFA 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.
conclusionsCollectively, 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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