Korean Journal of Pain最新文献

{"title":"Measurement of S1 foramen depth for ultrasound-guided S1 transforaminal epidural injection.","authors":"Ye Sull Kim,&nbsp;SeongOk Park,&nbsp;Chanhong Lee,&nbsp;Sang-Kyi Lee,&nbsp;A Ram Doo,&nbsp;Ji-Seon Son","doi":"10.3344/kjp.22227","DOIUrl":"https://doi.org/10.3344/kjp.22227","url":null,"abstract":"<p><strong>Background: </strong>Ultrasound-guided first sacral transforaminal epidural steroid injection (S1 TFESI) is a useful and easily applicable alternative to fluoroscopy or computed tomography (CT) in lumbosacral radiculopathy. When a needle approach is used, poor visualization of the needle tip reduces the accuracy of the procedure, increasing its difficulty. This study aimed to improve ultrasound-guided S1 TFESI by evaluating radiological S1 posterior foramen data obtained using three-dimensional CT (3D-CT).</p><p><strong>Methods: </strong>Axial 3D-CT images of the pelvis were retrospectively analyzed. The radiological measurements obtained from the images included 1st posterior sacral foramen depth (S1D, mm), 1st posterior sacral foramen width (S1W, mm), the angle of the 1st posterior sacral foramen (S1A, °), and 1st posterior sacral foramen distance (S1ds, mm). The relationship between the demographic factors and measured values were then analyzed.</p><p><strong>Results: </strong>A total of 632 patients (287 male and 345 female) were examined. The mean S1D values for males and females were 11.9 ± 1.9 mm and 10.6 ± 1.8 mm, respectively (<i>P</i> < 0.001); the mean S1A 28.2 ± 4.8° and 30.1 ± 4.9°, respectively (<i>P</i> < 0.001); and the mean S1ds, 24.1 ± 2.9 mm and 22.9 ± 2.6 mm, respectively (<i>P</i> < 0.001); however, the mean S1W values were not significantly different. Height was the only significant predictor of S1D (β = 0.318, <i>P</i> = 0.004).</p><p><strong>Conclusions: </strong>Ultrasound-guided S1 TFESI performance and safety may be improved with adjustment of needle insertion depth congruent with the patient's height.</p>","PeriodicalId":56252,"journal":{"name":"Korean Journal of Pain","volume":"36 1","pages":"98-105"},"PeriodicalIF":2.8,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/7e/cb/kjp-36-1-98.PMC9812692.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10519988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A positive feedback loop of heparanase/syndecan1/nerve growth factor regulates cancer pain progression.","authors":"Xiaohu Su,&nbsp;Bingwu Wang,&nbsp;Zhaoyun Zhou,&nbsp;Zixian Li,&nbsp;Song Tong,&nbsp;Simin Chen,&nbsp;Nan Zhang,&nbsp;Su Liu,&nbsp;Maoyin Zhang","doi":"10.3344/kjp.22277","DOIUrl":"https://doi.org/10.3344/kjp.22277","url":null,"abstract":"<p><strong>Background: </strong>The purpose of this research was to assess the role of heparanase (HPSE)/syndecan1 (SDC1)/nerve growth factor (NGF) on cancer pain from melanoma.</p><p><strong>Methods: </strong>The influence of HPSE on the biological function of melanoma cells and cancer pain in a mouse model was evaluated. Immunohistochemical staining was used to analyze HPSE and SDC1. HPSE, NGF, and SDC1 were detected using western blot. Inflammatory factors were detected using ELISA assay.</p><p><strong>Results: </strong>HPSE promoted melanoma cell viability, proliferation, migration, invasion, and tumor growth, as well as cancer pain, while SST0001 treatment reversed the promoting effect of HPSE. HPSE up-regulated NGF, and NGF feedback promoted HPSE. High expression of NGF reversed the inhibitory effect of HPSE down-regulation on melanoma cell phenotype deterioration, including cell viability, proliferation, migration, and invasion. SST0001 down-regulated SDC1 expression. SDC1 reversed the inhibitory effect of SST0001 on cancer pain.</p><p><strong>Conclusions: </strong>The results showed that HPSE promoted melanoma development and cancer pain by interacting with NGF/SDC1. It provides new insights to better understand the role of HPSE in melanoma and also provides a new direction for cancer pain treatment.</p>","PeriodicalId":56252,"journal":{"name":"Korean Journal of Pain","volume":"36 1","pages":"60-71"},"PeriodicalIF":2.8,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/c4/17/kjp-36-1-60.PMC9812689.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10868846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of ultrasound-guided subacromial corticosteroid and ozone (O₂-O₃) injections in the treatment of chronic rotator cuff tendinopathy: a randomized clinical trial.","authors":"Merve Örücü Atar,&nbsp;Nurdan Korkmaz,&nbsp;Sefa Gümrük Aslan,&nbsp;Özge Tezen,&nbsp;Sinem Uyar Köylü,&nbsp;Yasin Demir,&nbsp;Serdar Kesikburun","doi":"10.3344/kjp.22221","DOIUrl":"https://doi.org/10.3344/kjp.22221","url":null,"abstract":"<p><strong>Background: </strong>: The authors aimed to compare the effects of a one-time ultrasound (US)-guided subacromial corticosteroid injection and three-time ozone (O₂-O₃) injection in patients with chronic supraspinatus tendinopathy.</p><p><strong>Methods: </strong>: Participants were randomly assigned to the corticosteroid group (n = 22) or ozone group (n = 22). Injections in both groups were administered into subacromial bursa with an US-guided in-plane posterolateral approach. Primary outcome measure was the change in the Western Ontario Rotator Cuff Index (WORC) score between baseline and 12-weeks post-injection. Secondary outcome measures included visual analog scale and Shoulder Pain and Disability Index scores. Assessments were recorded at baseline, and 4-weeks and 12-weeks post-injection.</p><p><strong>Results: </strong>: Forty participants completed this study. Based on repeated measurement analysis of variance, a significant effect of time was found for all outcome measures in both groups. Both the groups showed clinically significant improvements in shoulder pain, quality of life, and function. Baseline, 4-week post-injection, and 12-week post-injection WORC scores (mean ± standard deviation) were 57.91 ± 18.97, 39.10 ± 20.50 and 37.22 ± 27.31 in the corticosteroid group, respectively and 69.03 ± 15.89, 39.11 ± 24.36, and 32.26 ± 24.58 in the ozone group, respectively. However, no significant group × time interaction was identified regarding all outcome measures.</p><p><strong>Conclusions: </strong>: Three-time ozone injection was not superior to a one-time corticosteroid injection in patients with chronic supraspinatus tendinopathy. It might be as effective as corticosteroid injection at 4-weeks and 12-weeks post-injection in terms of relieving pain and improving quality of life and function.</p>","PeriodicalId":56252,"journal":{"name":"Korean Journal of Pain","volume":"36 1","pages":"128-136"},"PeriodicalIF":2.8,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/c1/f2/kjp-36-1-128.PMC9812695.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9082738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prevention, diagnosis, and treatment of opioid use disorder under the supervision of opioid stewardship programs: it's time to act now.","authors":"Eun-Ji Kim,&nbsp;Eun-Jung Hwang,&nbsp;Yeong-Min Yoo,&nbsp;Kyung-Hoon Kim","doi":"10.3344/kjp.2022.35.4.361","DOIUrl":"10.3344/kjp.2022.35.4.361","url":null,"abstract":"<p><p>The third opium war may have already started, not only due to illicit opioid trafficking from the Golden Crescent and Golden Triangle on the international front but also through indiscriminate opioid prescription and opioid diversion at home. Opioid use disorder (OUD), among unintentional injuries, has become one of the top 4 causes of death in the United States (U.S.). An OUD is defined as a problematic pattern of opioid use resulting in clinically significant impairment or distress, consisting of 2 or more of 11 problems within 1 year, as described by the Diagnostic and Statistical Manual for Mental Disorders, Fifth Edition. Observation of aberrant behaviors of OUD is also helpful for overworked clinicians. For the prevention of OUD, the Opioid Risk Tool and the Current Opioid Misuse Measure are appropriate screening tests before and during opioid administration, respectively. Treatment of OUD consists of 3 opioid-based U.S. Food and Drug Administration-approved medications, including methadone, buprenorphine, and naltrexone, and non-opioid-based symptomatic medications for reducing opioid withdrawal syndromes, such as α2 agonists, β-blockers, antidiarrheals, antiemetics, non-steroidal anti-inflammatory drugs, and benzodiazepines. There are at least 6 recommendable guidelines and essential terms related to OUD. Opioid stewardship programs are now critical to promoting appropriate use of opioid medications, improving patient outcomes, and reducing misuse of opioids, influenced by the successful implementation of antimicrobial stewardship programs. Despite the lack of previous motivation, now is the critical time for trying to reduce the risk of OUD.</p>","PeriodicalId":56252,"journal":{"name":"Korean Journal of Pain","volume":"35 4","pages":"361-382"},"PeriodicalIF":2.8,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/5a/e2/kjp-35-4-361.PMC9530691.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40382296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum: Synergistic interaction between acetaminophen and L-carnosine improved neuropathic pain via NF-κB pathway and antioxidant properties in chronic constriction injury model.","authors":"Bamidele Victor Owoyele,&nbsp;Ahmed Olalekan Bakare,&nbsp;Olutayo Folajimi Olaseinde,&nbsp;Mohammed Jelil Ochu,&nbsp;Akorede Munirdeen Yusuff,&nbsp;Favour Ekebafe,&nbsp;Oluwadamilare Lanre Fogabi,&nbsp;Roi Treister","doi":"10.3344/kjp.2022.35.4.488","DOIUrl":"https://doi.org/10.3344/kjp.2022.35.4.488","url":null,"abstract":"","PeriodicalId":56252,"journal":{"name":"Korean Journal of Pain","volume":"35 4","pages":"488"},"PeriodicalIF":2.8,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/4b/8f/kjp-35-4-488.PMC9530685.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40382706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predictive factors associated with successful response to utrasound guided genicular radiofrequency ablation.","authors":"Selin Guven Kose,&nbsp;Halil Cihan Kose,&nbsp;Feyza Celikel,&nbsp;Omer Taylan Akkaya","doi":"10.3344/kjp.2022.35.4.447","DOIUrl":"https://doi.org/10.3344/kjp.2022.35.4.447","url":null,"abstract":"<p><strong>Background: </strong>Ultrasound-guided genicular nerve radiofrequency (RF) procedures are of interest in the management of chronic knee pain. A wide variety of demographic, clinical, and procedural characteristics can affect treatment success. This study aimed to determine predictive factors to provide superior treatment outcomes.</p><p><strong>Methods: </strong>The demographic, clinical, and technical data of patients who received genicular nerve RF for knee pain between September 2016 and September 2021 were evaluated. A positive outcome was defined as at least 50% pain relief on a pain score for at least 6 months. Logistic regression analysis was performed to determine the factors associated with a successful response to genicular RF.</p><p><strong>Results: </strong>Among 206 patients who underwent genicular RF, 62% of the patients reported successful outcomes at 6 months. In the multivariate model, targeting 5 nerves (odds ratio [OR], 6.184; 95% confidence interval [CI], 2.291-16.690; <i>P</i> < 0.001) was the most significant predictor of successful outcomes. Multivariable logistic regression analysis showed that prognostic genicular nerve block with a 50% cut-off value (OR, 2.109; 95% CI, 1.038-4.287; <i>P</i> = 0.039), no opioid use (OR, 2.753; 95% CI, 1.405-5.393; <i>P</i> = 0.003), and depression (OR, 0.297; 95% CI, 0.124-0.713; <i>P</i> = 0.007) were the predictive factors significantly associated with response to genicular RF.</p><p><strong>Conclusions: </strong>Clinical and technical factors associated with better treatment outcomes were ultimately targeting more nerves, performing prognostic block, no opioid use, and no depression. These results are expected to be considered when selecting patients for genicular RF.</p>","PeriodicalId":56252,"journal":{"name":"Korean Journal of Pain","volume":"35 4","pages":"447-457"},"PeriodicalIF":2.8,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/b2/ad/kjp-35-4-447.PMC9530687.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40383235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Post-COVID-19 pain syndrome: a descriptive study in Turkish population.","authors":"İlknur Topal,&nbsp;Necdet Özçelik,&nbsp;Ali Timuçin Atayoğlu","doi":"10.3344/kjp.2022.35.4.468","DOIUrl":"https://doi.org/10.3344/kjp.2022.35.4.468","url":null,"abstract":"<p><strong>Background: </strong>The new type of corona virus has a wide range of symptoms. Some people who have COVID-19 can experience long-term effects from their infection, known as post-COVID conditions. The authors aimed to investigate prolonged musculoskeletal pain as a symptom of the post-COVID-19 condition.</p><p><strong>Methods: </strong>This is a descriptive study on the patients who were diagnosed with COVID-19 in a university hospital, between March 2020 and March 2021. Patient records and an extensive questionnaire were used to obtain relevant demographic and clinical characteristics, including hospitalization history, comorbidities, smoking history, duration of the pain, the area of pain, and the presence of accompanying neuropathic symptoms.</p><p><strong>Results: </strong>Of the diagnosed patients, 501 agreed to participate in the study. Among the participants, 318 had musculoskeletal pain during COVID-19 infection, and 69 of them reported prolonged pain symptoms as part of their a post-COVID condition which could not be attributed to any other cause. The mean duration of pain was 4.38 ± 1.73 months, and the mean pain level was 7.2 ± 4.3. Neuropathic pain symptoms such as burning sensation (n = 16, 23.2%), numbness (n = 15, 21.7%), tingling (n = 10, 14.5%), stinging (n = 4, 5.8%), freezing (n = 1, 1.4%) were accompanied in patients with prolonged musculoskeletal pain.</p><p><strong>Conclusions: </strong>Patients with COVID-19 may develop prolonged musculoskeletal pain. In some patients, neuropathic pain accompanies it. Awareness of prolonged post-COVID-19 pain is crucial for its early detection and management.</p>","PeriodicalId":56252,"journal":{"name":"Korean Journal of Pain","volume":"35 4","pages":"468-474"},"PeriodicalIF":2.8,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/e3/96/kjp-35-4-468.PMC9530682.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40382705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Actual situation and prescribing patterns of opioids by pain physicians in South Korea.","authors":"Min Jung Kim,&nbsp;Ji Yeon Kim,&nbsp;Yun Hee Lim,&nbsp;Sung Jun Hong,&nbsp;Jae Hun Jeong,&nbsp;Hey Ran Choi,&nbsp;Sun Kyung Park,&nbsp;Jung Eun Kim,&nbsp;Min Ki Lee,&nbsp;Jae Hun Kim","doi":"10.3344/kjp.2022.35.4.475","DOIUrl":"https://doi.org/10.3344/kjp.2022.35.4.475","url":null,"abstract":"<p><strong>Background: </strong>Use of opioids for chronic intractable pain is increasing globally, and their proper use can improve patients' quality of life. In contrast, opioid use disorders, such as abuse or addiction, caused by prescribing opioids, are a worldwide issue. This study aimed to understand current opioid prescribing patterns and pain physicians' experiences with opioid use in South Korea.</p><p><strong>Methods: </strong>Pain physicians in 42 university hospitals in South Korea were asked to complete anonymous questionnaires regarding opioid prescriptions.</p><p><strong>Results: </strong>A total of 69 surveys were completed. Most pain physicians started prescribing opioids at a pain score of 7/10 and aimed to reduce pain by 50%. Most physicians (73.1%) actively explained the prescribed medications and possible side effects, and 61.2% of physicians preferred the prescription interval of 4 weeks. Immediate-release opioids were the most popular treatment for breakthrough pain (92.6%). The most common side effect encountered by physicians was constipation (43.3%), followed by nausea/vomiting (34.3%). Of the physicians, 56.5% replied that addiction and misuse prevalences were less than 5%. However, the most concerning side effect was addiction (33.0%).</p><p><strong>Conclusions: </strong>The survey results showed that the prescribing patterns of pain physicians generally followed Korean guidelines. Physicians were most interested in the safety and effectiveness of opioid prescriptions. They were most concerned about respiratory depression and abuse or addiction. A significant number of physicians agreed that the NHIS regulations needed improvement for patient convenience and safe and effective treatment, though there were pros and cons of the NHIS restrictions on prescription conditions.</p>","PeriodicalId":56252,"journal":{"name":"Korean Journal of Pain","volume":"35 4","pages":"475-487"},"PeriodicalIF":2.8,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/bc/16/kjp-35-4-475.PMC9530690.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40382707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of pre-procedure virtual simulation for challenging interventional procedures: an experimental study with clinical application.","authors":"Hyunyoung Seong,&nbsp;Daehun Yun,&nbsp;Kyung Seob Yoon,&nbsp;Ji Soo Kwak,&nbsp;Jae Chul Koh","doi":"10.3344/kjp.2022.35.4.403","DOIUrl":"https://doi.org/10.3344/kjp.2022.35.4.403","url":null,"abstract":"<p><strong>Background: </strong>Most pain management techniques for challenging procedures are still performed under the guidance of the C-arm fluoroscope although it is sometimes difficult for even experienced clinicians to understand the modified three-dimensional anatomy as a two-dimensional X-ray image. To overcome these difficulties, the development of a virtual simulator may be helpful. Therefore, in this study, the authors developed a virtual simulator and presented its clinical application cases.</p><p><strong>Methods: </strong>We developed a computer program to simulate the actual environment of the procedure. Computed tomography (CT) Digital Imaging and Communications in Medicine (DICOM) data were used for the simulations. Virtual needle placement was simulated at the most appropriate position for a successful block. Using a virtual C-arm, the authors searched for the position of the C-arm at which the needle was visualized as a point. The positional relationships between the anatomy of the patient and the needle were identified.</p><p><strong>Results: </strong>For the simulations, the CT DICOM data of patients who visited the outpatient clinic was used. When the patients revisited the clinic, images similar to the simulated images were obtained by manipulating the C-arm. Transforaminal epidural injection, which was difficult to perform due to severe spinal deformity, and the challenging procedures of the superior hypogastric plexus block and Gasserian ganglion block, were successfully performed with the help of the simulation.</p><p><strong>Conclusions: </strong>We created a pre-procedural virtual simulation and demonstrated its successful application in patients who are expected to undergo challenging procedures.</p>","PeriodicalId":56252,"journal":{"name":"Korean Journal of Pain","volume":"35 4","pages":"403-412"},"PeriodicalIF":2.8,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/e6/61/kjp-35-4-403.PMC9530692.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40383230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spinal orexin A attenuates opioid-induced mechanical hypersensitivity in the rat.","authors":"Dong-Ho Youn,&nbsp;Jiyeon Jun,&nbsp;Tae Wan Kim,&nbsp;Kibeom Park","doi":"10.3344/kjp.2022.35.4.433","DOIUrl":"https://doi.org/10.3344/kjp.2022.35.4.433","url":null,"abstract":"<p><strong>Background: </strong>Repeated administration of opioid analgesics for pain treatment can produce paradoxical hyperalgesia via peripheral and/or central mechanisms. Thus, this study investigated whether spinally (centrally) administered orexin A attenuates opioid-induced hyperalgesia (OIH).</p><p><strong>Methods: </strong>[D-Ala2, N-Me-Phe4, Gly5-ol]-enkephalin (DAMGO), a selective μ-opioid receptor agonist, was used to induce mechanical hypersensitivity and was administered intradermally (4 times, 1-hour intervals) on the rat hind paw dorsum. To determine whether post- or pretreatments with spinal orexin A, dynorphin A, and anti-dynorphin A were effective in OIH, the drugs were injected through an intrathecal catheter whose tip was positioned dorsally at the L3 segment of the spinal cord (5 μg for all). Mechanical hypersensitivity was assessed using von Frey monofilaments.</p><p><strong>Results: </strong>Repeated intradermal injections of DAMGO resulted in mechanical hypersensitivity in rats, lasting more than 8 days. Although the first intrathecal treatment of orexin A on the 6th day after DAMGO exposure did not show any significant effect on the mechanical threshold, the second (on the 8th day) significantly attenuated the DAMGO-induced mechanical hypersensitivity, which disappeared when the type 1 orexin receptor (OX1R) was blocked. However, intrathecal administration of dynorphin or an anti-dynorphin antibody (dynorphin antagonists) had no effect on DAMGO-induced hypersensitivity. Lastly, pretreatment with orexin A, dynorphin, or anti-dynorphin did not prevent DAMGO-induced mechanical hypersensitivity.</p><p><strong>Conclusions: </strong>Spinal orexin A attenuates mechanical hyperalgesia induced by repetitive intradermal injections of DAMGO through OX1R. These data suggest that OIH can be potentially treated by activating the orexin A-OX1R pathway in the spinal dorsal horn.</p>","PeriodicalId":56252,"journal":{"name":"Korean Journal of Pain","volume":"35 4","pages":"433-439"},"PeriodicalIF":2.8,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/08/e9/kjp-35-4-433.PMC9530684.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40383233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}