• Biomolecules & Therapeutics
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• 제25권3호
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• pp.259-265
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• 2017

This study aimed to investigate the analgesic effect of substance P (SP) in an animal model of neuropathic pain. An experimental model of neuropathic pain, the chronic constriction injury (CCI) model, was established using ICR mice. An intravenous (i.v.) injection of SP (1 nmole/kg) was administered to the mice to examine the analgesic effects of systemic SP on neuropathic pain. Behavioral testing and immunostaining was performed following treatment of the CCI model with SP. SP attenuated mechanical allodynia in a time-dependent manner, beginning at 1 h following administration, peaking at 1 day post-injection, and decaying by 3 days post-injection. The second injection of SP also increased the threshold of mechanical allodynia, with the effects peaking on day 1 and decaying by day 3. A reduction in phospho-ERK and glial fibrillary acidic protein (GFAP) accompanied the attenuation of mechanical allodynia. We have shown for the first time that i.v. administration of substance P attenuated mechanical allodynia in the maintenance phase of neuropathic pain using von Frey's test, and simultaneously reduced levels of phospho-ERK and GFAP, which are representative biochemical markers of neuropathic pain. Importantly, glial cells in the dorsal horn of the spinal cord (L4-L5) of SP-treated CCI mice, expressed the anti-inflammatory cytokine, IL-10, which was not seen in vehicle saline-treated mice. Thus, i.v. administration of substance P may be beneficial for improving the treatment of patients with neuropathic pain, since it decreases the activity of nociceptive factors and increases the expression of anti-nociceptive factors.

• The Korean Journal of Pain
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• 제36권1호
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• pp.106-112
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• 2023

Background: Most international bodies recommended against musculoskeletal steroid injection during the COVID-19 pandemic, fearing that the immunosuppressive effects of the steroid could worsen COVID-19 infection, thus prolonging the suffering of patients with severe musculoskeletal disease. The authors' aim is to analyze the risk of COVID-19 infection after musculoskeletal injections. Methods: This is a retrospective study of patients who visited a sports medicine clinic and received musculoskeletal steroid injections between January 1, 2020 and February 28, 2021. The collected data was compared with the national COVID-19 registry to identify positive COVID-19 patients. The patients were only considered positive for COVID-19 following corticosteroid injection within 3 months after injection. Results: Out of 502 steroid injections; 79.7% (n = 400) received a single injection in one day, 19.1% (n = 96) received steroid injections at 2 sites in one day, and 1.2% (n = 6) received steroid injections at 3 sites in one day. Using the Fisher's exact test, there was no statistically significant association of COVID-19 infection between the steroid group and control group (relative risk, 1.44; 95% confidence interval, 0.9-23.1, P = 0.654). Only one patient contracted mild COVID-19 with no post COVID complications. Conclusions: The authors recommend the use of musculoskeletal steroid injections in clinically indicated situation without having increased risk of COVID-19.

• Korean Journal of Acupuncture
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• 제21권2호
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• pp.47-67
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• 2004

Objectives : In the present study, the effect of Scolopendrid Water-Alcohol Extract (SWAE) applied to acupuncture point BL23 (Shinsu) on the neuropathic pain was examined. A common source of persistent pain in humans is the neuropathic pain. Anti-convulsant drugs are used to treat the neuropathic pain. In the oriental medicine, Scolopendrid was used for long time to treat convulsant syndrome and back pain, etc. Methods : On the bases of the Scolopendrid clinical application, the effect of SWAE applied to the acupuncture point was tested in the rat model of neuropathic pain. Neuropathic pain was induced by tight ligation of L5 spinal nerve. When rats developed pain behaviors, One hundred microliter of SWAE was applied into the ipsilateral BL23 point at a dose of 10 mg/ml under enflurane anesthesia. The foot withdraw latency of the hind limb was measured for an indicator of pain level after each manipulation. Results : SWAE injection increased the mechanical threshold of the foot in the rat model of neuropathic pain significantly for the duration of 4h, suggesting a partial alleviation of pain. SWAE applied to BL23 point produced a significant improvement of mechanical sensitivity of the foot lasting for at least 4h. However, neither contralateral BL23 point, ST25 (Chonchu) point, nor LR3 (Taechung) point produce as much increase of mechanical sensitivity as ipsilateral BL23 point. And, this increase of mechanical sensitivity was dose-dependent. The improvement of mechanical threshold was interpreted as an analgesic effect. In addition, the analgesic effect of Scolopendrid 4 mg/kg injection is equivalent to that of gabapentin 50 mg/kg injection. The relations between SWAE-induced analgesia and endogenous nitric oxide(NO), inducible NO synthase (iNOS)/neuronal NO synthase (nNOS) were also examined. Results were turned out that both NO production and nNOS/iNOS protein expression which are increased by nerve injury were suppressed by SWAE injection applied to BL23 point. Conclusions : The data suggest 1) that SWAE produces a potent analgesic effect on the neuropathic pain model in the rat and 2) that SWAE-induced analgesia modulate endogenous NO through the suppression of nNOS/iNOS protein expression.

• The Korean Journal of Pain
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• 제26권4호
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• pp.387-391
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• 2013

A 64-year-old woman visited our pain clinic with the pain of right lateral side of thigh for one year. Her pain always started from knee and was radiated to buttock area when symptom was severe. She showed significant tenderness at knee lateral side and local tightness at lateral thigh. Magnetic resonance image of the knee was performed and we could identify high signal intensity of iliotibial band through coronal and axial view. In spite of medication and physical stretching exercise of iliotibial band for one month, she did not show any improvement of pain. To alleviate her symptom, ultrasound guided local corticosteroid injection targeting beneath the iliotibial band was performed. After the procedure, the reduction of pain was significant and there was no need for further management.

• The Korean Journal of Pain
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• 제33권4호
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• pp.326-334
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• 2020

Background: In this study, we sought to evaluate whether systemic propentofylline (PPF) has antiallodynic effects in a rat model of postoperative pain, and to assess the mechanism involved. Methods: After plantar incision, rats were intraperitoneally injected with various doses of PPF to evaluate its antiallodynic effect. To investigate the involved mechanism, rats were intraperitoneally injected with yohimbine, dexmedetomidine, prazosin, naloxone, atropine or mecamylamine, following the incision of the rat hind paws, and then PPF was administered intraperitoneally. The mechanical withdrawal threshold (MWT) was evaluated using von Frey filaments at various time points and serum levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 were measured to determine the inflammatory response level. Results: MWT was significantly increased after intraperitoneal injection of 30 mg/kg of PPF when compared with the control group. Injection of PPF and yohimbine, atropine or mecamylamine showed significant decreases in the MWT, while injection of PPF and dexmedetomidine showed a significant increase. Systemic administration of PPF inhibited the post-incisional increase in serum level of TNF-α and IL-1β. Conclusions: Systemic administration of PPF following surgery presented antiallodynic effects in a rat model of postoperative pain. The antiallodynic effects against mechanical allodynia could be mediated by α-adrenergic and cholinergic receptors.

• The Korean Journal of Pain
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• 제20권2호
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• pp.92-99
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• 2007

Background: A correlation between a T-type voltage activated calcium channel (VACC) and pain mechanism has not yet been established. The purpose of this study is to find out the effect of ethosuximide and mibefradil, representative selective T-type VACC blockers on postoperative pain using an incisional pain model of rats. Methods: After performing a plantar incision, rats were stabilized on plastic mesh for 2 hours. Then, the rats were injected with ethosuximide or mibefradil, intraperitoneally and intrathecally. The level of withdrawal threshold to the von Frey filament near the incision site was determined and the dose response curves were obtained. Results: After an intraperitoneal ethosuximide or mibefradil injection, the dose-response curve showed a dose-dependent increase of the threshold in a withdrawal reaction. After an intrathecal injection of ethosuximide, the threshold of a withdrawal reaction to mechanical stimulation increased and the increase was dose-dependent. After an intrathecal injection of mibefradil, no change occurred in either the threshold of a withdrawal reaction to mechanical stimulation or a dose-response curve. Conclusions: The T-type VACC blockers in a rat model of postoperative pain showed the antihyperalgesic effect. This effect might be due to blockade of T-type VACC, which was distributed in the peripheral nociceptors or at the supraspinal level. Further studies of the effect of T-type VACC on a pain transmission mechanism at the spinal cord level would be needed.

• The Korean Journal of Pain
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• 제18권2호
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• pp.124-132
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• 2005

Background: This study was performed to evaluate the dose-related effects of naloxone on morphine analgesia in the rat formalin test, and observe the correlation of pain behavior and spinal c-fos expression induced by a formalin injection. Methods: Fifty rats were divided into five groups; control, morphine (morphine pre-treated, intra-peritoneal injection of 0.1 mg of morphine 5 min prior to formalin injection), and three naloxone groups, which were divided according to the administered dose-ratio of naloxone to morphine 20 : 1 ($5{\mu}g$), 10 : 1 ($10{\mu}g$), and 1 : 1 ($100{\mu}g$) representing the low-, medium-, and high-dose naloxone groups, respectively, were injected intra-peritoneally 16 min after a formalin. A fifty ul of 5% formalin was injected into the right hind paw. All rats were observed for their pain behavior according to the number of flinches during phases 1 (2-3, 5-6 min) and 2 (1 min per every 5 min from 10 to 61 min). The spinal c-fos expression was quantitatively analyzed at 1 and 2 hours after the formalin injection using a real-time PCR. Results: The morphine pre-treated (morphine and three naloxone) groups during phase 1, and the morphine, low- and medium-dose naloxone groups during phase 2, showed significantly less flinches compared to those of the control (P < 0.05). In the three naloxone groups, the numbers of flinches were transiently reduced following the naloxone injection in the low- and medium-dose groups compared to those of the morphine group (P < 0.05). The duration of the reduced flinches was longer in the medium-dose group (P < 0.05). The high-dose group revealed immediate increases in flinches immediately after the naloxone injection compared to those of the morphine, low- and medium-dose groups (P < 0.05 for each). The spinal c-fos expression showed no significant patterns between the experimental groups. Conclusions: Our data suggest that relatively low-dose naloxone (1/20 to 1/10 dose-ratio of morphine) transiently potentiates morphine analgesia; whereas, high-dose (equal dose-ratio of morphine) reverses the analgesia, and the spinal c-fos expression does not always correlate with pain behavior in the rat formalin test.

• The Korean Journal of Pain
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• 제31권4호
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• pp.289-295
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• 2018

Background: The intraarticular (IA) injection has become popular for the management of the osteoarthritic knee without an effusion. The success rate of IA injection would be better if it was able to be visually confirmed. We hypothesized that an anterolateral approach, which targets the synovial membrane of the lateral condyle using ultrasound, would provide an equivalent alternative to the anterolateral approach, targeting the synovial membrane of the medial condyle for IA injection of the knee. Methods: A total of 96 knees with osteoarthritis were randomized placed into the two groups, which were group I (anterolateral approach to the medial condyle) and group II (anterolateral approach to the lateral condyle). The primary outcome was to compare the success rate of the two methods of IA injection. The required length of the needle for injection was also measured and compared. Pain intensity was assessed using the Numeric Rating Scale in order to evaluate the success of injection. Results: There were no significant differences in the success rate between both groups. The success rate of group I and group II were 87.8% (95%, CI 78.7-97.0) and 91.5% (95%, CI 83.6-99.5), respectively (P = 0.549). The needle depth was $5.0{\pm}0.8$ (3.0 to 6.1 cm) in group I, and $3.0{\pm}0.8$ (1.5 to 5 cm) in group II (P < 0.001). Conclusions: The anterolateral approach to the lateral femoral condyle, using ultrasound, is an alternative method to the approach targeting the medial femoral condyle, using shorter needle.

• The Korean Journal of Pain
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• 제8권2호
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• pp.235-243
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• 1995

A retrospective study was performed to evaluate the effects, and side effects, of epidural analgesia for postoperative pain relief of 2,381 surgical patients who received general-epidural, or epidural anesthesia only. Anesthesia records, patients charts, and pain control records were reviewed and classified according to: age, sex, body weight, department, operation site, epidural puncture site, degree of pain relief by injection mode & epidural injectate, and side effects(including nausea, vomiting, pruritus, urinary retention and respiratory depression). The results were as follows: 1) From the total of 2,381 patients, there were 1,563(66%) female patients; 1.032(43%) patients were from Obstetrics and Gynecology. 2) Lower abdomen, thorax, lower extremity and upper abdomen in the operation site; and lumbar, upper, lower thoracic in puncture site were order of decreasing frequency. Length of epidural injection for pain relief averaged $1.72{\pm}1.02$ days. 3) Ninety three percent of the patients experienced mild or no pain in the postoperative course. Analgesic quality was not affected by the kind of epidural injectate. 4) Nausea occurred in 3.2% of all patients, vomiting in 1.1%, pruritus 0.9%, urinary retention 0.6%, respiratory depression 0.08%. 5) Frequency of nausea was higher with female patients compared to male patients(p<0.05). 6) Pruritus frequency was higher with male patients than female patients(p<0.05); and more frequent with patients who received epidural injection with morphine than patients who received epidural injection without morphine(p<0.01). 7) Urinary retention was higher in female patients, and more frequent with patients who had received epidural injection with morphine than epidural injection without morphine(p<0.05). 8) There were two cases of respiratory depression. The course of treatment consisted of: cessation of epidural infusion, then administration of oxygen and intravenous naloxone. We conclude that postoperative epidural analgesia with a combination of local anesthetics and opiate is and effective method for postoperative pain relief with low incidence of side effects. However, patients should be carefully evaluated as rare but severe complications of respiratory depression may ensue.

• Child Health Nursing Research
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• 제13권1호
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• pp.66-72
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• 2007

Purpose: This study was done to evaluate the effects of distraction using balloon art on pain experienced by preschool children when undergoing an intravenous injection. Methods: Participants were 40 hospitalized preschool children. Children in the experimental group (20) were distracted by balloon art while undergoing an intravenous injection. Children in the control group (20) received regular care. Pain experienced by the children was measured using self-report, observation tools, heart rate and oxygen saturation. The data were analyzed using the SAS program. Results: Compared with the control group, children in the experimental group showed significant difference in pain as shown by pulse rate. However, children in the experimental group did not show a decrease in pain in the self-report or behavior observation when compared with children in the control group. Conclusion: Distraction using balloon art can be used to reduce pain for preschool children when undergoing an intravenous injection. Further nursing interventions need to be developed and provided to preschool children when undergoing painful procedures.