ArticleExperimental and therapeutic medicine2015
Analgesic roles of peripheral intrinsic met-enkephalin and dynorphin A in long-lasting inflammatory pain induced by complete Freund's adjuvant in rats.
Article in Experimental and therapeutic medicine, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers.
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14 citing papers in PubMed, 25 citations in OpenAlex.
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- Microiontophoretic Application of Dynorphin in Dental Pain: Excitatory or Inhibitory Effects.Journal of pain research · 2025Article
- The Double Insult of Neonatal Cystitis Plus Adult Somatic Inflammation Results in Corticotropin Releasing Factor Type II Receptor-Dependent Bladder Hypersensitivity in Female Rats.The journal of pain · 2022Article
- Opioids and Ocular Surface Pathology: A Literature Review of New Treatments Horizons.Journal of clinical medicine · 2022Review
- Inflammatory and healing environment in synovial fluid after anterior cruciate ligament reconstruction: Granulocytes and endogenous opioids as new targets of postoperative pain.Biochemistry and biophysics reports · 2021Article
- Positive allosteric modulation of the mu-opioid receptor produces analgesia with reduced side effects.Proceedings of the National Academy of Sciences of the United States of America · 2021Article
- Effect of Moxibustion onEvidence-based complementary and alternative medicine : eCAM · 2021Article
- Peripherally Acting Opioids in Orofacial Pain.Frontiers in neuroscience · 2021Review
- Dual-Acting Peripherally Restricted Delta/Kappa Opioid (CAV1001) Produces Antinociception in Animal Models of Sub-Acute and Chronic Pain.Journal of pain research · 2020Article
- Modulation of the Negative Affective Dimension of Pain: Focus on Selected Neuropeptidergic System Contributions.International journal of molecular sciences · 2019Review
- Analgesic Effect of Moxibustion with Different Temperature on Inflammatory and Neuropathic Pain Mice: A Comparative Study.Evidence-based complementary and alternative medicine : eCAM · 2017Article
- Chitosan Oligosaccharide Reduces Propofol Requirements and Propofol-Related Side Effects.Marine drugs · 2016Article
- Article
- Effects of electroacupuncture at 2 and 100 Hz on rat type 2 diabetic neuropathic pain and hyperalgesia-related protein expression in the dorsal root ganglion.Journal of Zhejiang University. Science. BArticle
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7 authors at 1 institution in 1 country.
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No grant is acknowledged in the PubMed record.
Abstract
Previous studies have focused on strategies for pain relief based on the peripheral opioid system. However, little is known with regard to the profile of the peripheral opioid system in long-lasting inflammatory pain. In the current study, the intrinsic changes of the peripheral opioids were investigated in long-lasting inflammatory pain. A rat model of complete Freund's adjuvant (CFA)-induced inflammatory pain was established. Paw swelling and thermal hyperalgesia (paw withdrawal latency, PWL) were analyzed until day 18 after the CFA injection. The levels of peripheral opioids and their upstream inducers, corticotrophin-releasing factor (CRF) and interleukin (IL)-1β, were measured, and validation experiments were performed using opioid receptor antagonists. Long-lasting inflammatory pain was successfully induced in the rats, as shown by the significantly increased paw swelling and decreased PWLs. On day 18 after the CFA injection, the IL-1β levels were significantly elevated, while CRF remained at a normal level in the paw inflammatory tissue. In addition, met-enkephalin (Met-ENK) and dynorphin A (DYN A) levels were significantly increased, while the β-endorphin level remained normal. Local intraplantar administration of δ- and κ-opioid receptor antagonists resulted in more substantial pain, but did not significantly affect the PWLs of the normal control rats. Therefore, the results indicated that the increased levels of local Met-ENK and DYN A in CFA-induced long-lasting inflammatory pain may be involved in peripheral intrinsic analgesia.
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