• The Korean Journal of Pain
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• 제14권2호
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• pp.150-155
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• 2001

Background: Tramadol is known to be a weak opioid. However, it has also been shown that tramadol is an effective norepinephrine and serotonin uptake blocker, which may be effective in the treatment of neuropathic pain. The present study was undertaken in order to assess the antinociceptive action of tramadol and to investigate possible antinociceptive mechanisms by using antagonists in an animal neuropathic pain models in rats. Methods: Rats were prepared with tight ligation at the left 5 and 6th lumbar spinal nerves (Kim and Chung's neuropathic pain model). The antinociceptive effects of tramadol (10, 20, and 50 mg/kg i.p.) in rats with neuropathic pain were assessed. Additionally, following coadministration of antagonists such as naloxone (1 mg/kg i.p.), yohimbine (1 mg/kg i.p.) and ritanserin (1 mg/kg i.p.) with 50 mg/kg of tramadol, the responses to mechanical and thermal stimuli were measured over a two-hour period. Results: Tramadol displayed potent antinociceptive effects in a dose-dependent manner on rats with neuropathic pain (P < 0.05). The effects of tramadol were inhibited by coadministered naloxone and yohimbine in rats with mechanical and thermal allodynia, respectively (P < 0.05). However, there were no significant changes in the pain behaviors in the case of ritanserin. Conclusions: Tramadol showed significant antinociceptive effects in rats with regards to neuropathic pain against both mechanical and thermal allodynia. The antinociceptive effect on the mechanical stimuli is medicated via an opioid receptor. However, it appears that the antinociceptive effects on thermal allodynia are mediated via a noradrenalin receptor vice a serotonergic receptor.

• International Journal of Oral Biology
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• 제32권2호
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• pp.59-65
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• 2007

It has been well known that excitatory amino acids, primarily glutamate, are involved in the transmission of nociception in pathological and physiological conditions in the spinal and brainstem level. Recently, peripheral glutamate also play a critical role in the peripheral nociceptive transmissions. The present study investigated the role of N-methyl-D-aspartic acid (NMDA) or non-NMDA ionotropic glutamate receptors in formalin-induced TMJ pain. Experiments were carried out on male Sprague-Dawley rats weighing 220-280 g. Intra-articular injection was performed under halothane anesthesia. Under anesthesia, AP-7 (10, $100\;{\mu}M$, $1\;mM/20\;{\mu}L$), a NMDA receptor antagonist, or CNQX disodium salt (0.5, 5, 50, $500\;{\mu}M/20\;{\mu}L$), a non-NMDA receptor antagonist, were administered intra-articularly 10 min prior to the application of 5% formalin. For each animal, the number of behavioral responses, such as rubbing and/or scratching the TMJ region, was recorded for nine successive 5-min intervals. Intra-articular pretreatment with 1 mM of AP-7 or $50\;{\mu}M$ CNQX significantly decreased the formalin-induced scratching behavioral responses during the second phase. Intra-articular pretreatment with $500\;{\mu}M$ of CNQX significantly decreased the formalin-induced scratching behavior during both the first and the second phase. These results indicate that the intra-articular administration of NMDA or non-NMDA receptor antagonists inhibit formalin-induced TMJ nociception, and peripheral ionotropic glutamate receptors may play an important role in the TMJ nociception.

• BMB Reports
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• 제35권4호
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• pp.420-427
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• 2002

Partial nerve injury is the main cause of neuropathic pain disorders in humans. Acupuncture has long been used to relieve pain. It is known to relieve pain by controlling the activities of the autonomic nervous system. Although the mechanism of neuropathic pain and analgesic effects of electroacupuncture (EA) have been studied in a rat model system, its detailed mechanism at the molecular level remains unclear. To identify genes that might serve as either markers or explain these distinct biological functions, a cDNA microarray analysis was used to compare the expression of 8,400 genes among three sample groups. Messenger RNAs that were pooled from the spinal nerves of 7 normal. 7 neuropathic pain, and 7 EA treatment rat models were compared. Sixty-eight genes were differentially expressed more than 2-fold in the neuropathic rat model when compared to the normal, and restored to the normal expression level after the EA treatment. These genes are involved in a number of biological processes, including the signal transduction, gene expression, and nociceptive pathways. Confirmation of the differential gene expression was performed by a dot-blot analysis. Dot-blotting results showed that the opioid receptor sigma was among those genes. This indicates that opioid-signaling events are involved in neuropathic pain and the analgesic effects of EA. The potential application of these data include the identification and characterization of signaling pathways that are involved in the EA treatment, studies on the role of the opioid receptor in neuropathic pain, and further exploration on the role of selected identified genes in animal models.

• 한국임상수의학회지
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• 제22권4호
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• pp.408-411
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• 2005

Schistosomus reflexus is the most common monstrosity found in cases of bovine dystocia and it occurs mostly in cattle. Caesarian section performed and retracted abnormal foetus from dystocia in Holstein cow. It was the first observed schistosomus reflexus Holstein calf in Korea. The body and chest walls were bent laterally and dorsally leaving the thoracic and abdominal viscera exposed. Clefts of the sternum from part of the defect in which there is, simultaneously, lordosis, dorsal reflection of the ribs and complete eventration of viscera, severe ventral curvature of the spinal column, non-union of the pelvic symphysis and dorsal reflection of the pelvic bones with the occiput of the head lying near the sacrum. The limbs are usually ankylosed. The liver was abnormal in shape and cystic in nature. The lung was smaller and thymus were bigger than those of the normal calf, The ruminant stomach was normal, however, abomasum distended with amnionic fluid. The other organ including heart, spleen and internal organ have normal shape.

• Journal of Korean Neurosurgical Society
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• 제39권2호
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• pp.130-135
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• 2006

Objective : After ischemic stroke, partial recovery of function frequently occurs and may depend on the plasticity of axonal connections. Here, we examine whether blockade of the Nogo/NogoReceptor[NgR] pathway might enhance axonal sprouting and thereby recovery after focal brain infarction. Methods : Adult male Sprague Dawley rats weighing $250{\sim}350g$ were used. Left middle cerebral artery occlusion[MCAO] was induced with a intraluminal filament. An osmotic mini pump [Alzet 2ML4, Alza Scientific Products, Palo Alto, CA] for the infusion of NgR-Ecto[310]-Fc to block Nogo/NgR pathway was implanted 1 week after cerebral ischemia. Prior to induction of ischemia, all animals received training in the staircase and rotarod test. Two weeks after biotin dextran amine injection, animals were perfused transcardially with PBS, followed by 4% paraformadehyde/PBS solution. Brain and cervical spinal cord were dissected. Eight coronal sections spaced at 1mm intervals throughout the forebrain of each animal with cresyl violet acetate for determination of infarction size. Images of each section were digitized and the infarct area per section was measured with image analysis software. Results : Histological examination at 11 weeks post-MCAO demonstrates reproducible stroke lesions and no significant difference in the size of the stroke between the NgR[310]Ecto-Fc protein treated group and the control group. Behavioral recovery is significantly better and more rapid in the NgR-Ecto[310]-Fe treated group. Blockade of NgR enhances axonal sprouting from the uninjured cerebral cortex and improves the return of motor task performance. Conclusion : Pharmacological interruption of NgR allows a greater degree of axonal plasticity in response this is associated with improved functional recovery of complicated motor tasks.

• 대한수의학회지
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• 제39권4호
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• pp.715-723
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• 1999

Bee venom (BV) has been traditionally applied to relieve pain and to cure inflammatory diseases such as rheumatoid arthritis (RA) and neuritis. While several investigators have evaluated the anti-inflammatory effect of BV treatment, the anti-nociceptive effect of BV treatment on inflammatory pain is not reported. Therefore, we decided to evaluate the analgesic effect of BV treatment using Freund's adjuvant induced chronic arthritis model. Freund's adjuvant-induced arthritis has been used as an experimental animal model for RA in humans to assess the efficacy of the anti-inflammatory/analgesic drugs. In this study, subcutaneous BV treatment (1mg/kg/day) produced significantly reductions of symptoms related to arthritic pain (i.e. mechanical hyperalgesia and thermal hyperalgesia). The anti-nociceptive effect of BV was observed from at least 12 days after BV treatment. Furthermore, BV treatment significantly suppressed adjuvant induced Fos expression in lumbar spinal cord. We also found that local injection of BV into near the inflammatory site (especially Zusanli-acupoint) showed more potent analgesic effect on arthritic pain rather than distant injection of BV from inflammatory site (arbitrary side of back). The present study demonstrates that BV treatment has anti-nociceptive effect on arthritis induced inflammatory pain. The analgesic effect of BV on RA is probably mediated by the effect of BV itself or possible other mechanism such as counter-irritation. Furthermore, it is possible that BV acupuncture is one of the promising candidates for long-term therapy of RA.

• 한국수의병리학회지
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• 제2권2호
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• pp.117-125
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• 1998

Pathological studies were performed on the five piglets experimentally infected with Aujeszky's disease virus(pseudorabies), NYJ isolate, isolated from the naturally infected pigs in Korea: two piglets were inoculated intramuscularly, two piglets intranasally, and one piglet subcutaneously at the dose of 1$m\ell$ per animal with the 105.5 $TCID_50$/0.1ml titer. Clinical signs included dyspnea, high fever(＞$41^{\circ}C$), anorexia, vomiting, diarrhea or constipation, ataxia, circling movement, posterior paralysis, intermittent convulsion, and coma followed by death although some variations by age and inoculated routes were observed. Gross features included multiple necrotic foci in the liver, congestion and hemorrhage in the lymph nodes and spleen, petechial hemorrhage in the kidney, hemorrhagic pneumonia, marked meningeal congestion, severe sub meningeal hemorrhage in the spinal cord, excessive cerebrospinal fluid retention, and muscular necrosis at the inoculated area. Microscopically, non suppurative meningoencephalitis with gliosis and perivascular cuffing in CNS, ganglioneuritis, necrohemorrhagic splenitis, necrotic hepatitis, tonsillitis and rhinitis, hemorrhagic or interstitial pneumonia, and non-suppurative myositis in the injected area were observed. Eosinophilic intranuclear inclusion bodies were found in a variety of tissues the including the liver, kidney, adrenal gland, spleen, lymph nodes, tonsil, and lung. Ultrastructurally, virus particles were confirmed in nucleus and cytoplasms of pneumocytes around the necrotic areas.

• 한국임상수의학회지
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• 제31권5호
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• pp.439-444
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• 2014

체중 2.7 kg의 5세령 암컷 말티즈 견이 양측 슬개골 탈구와 후지 파행으로 지역동물병원에 내원하였다. 도르레절제술과 슬개골의 외측 보강 봉합법을 이용하여 슬개골 탈구 정복술을 실시하였으나, 수술 3주 후 등을 굽힌 자세의 보행과 후지의 운동실조, 흉요추부의 압통, 간헐적인 경련증상으로 재 내원하였다. 자기공명영상 촬영 결과, 우측 전두엽의 종괴와 경수에서부터 3번 요수까지의 공동성 변화가 확인되었다. 병리조직학적 소견으로 뇌종양은 느슨한 망상구조 또는 레이스 모양의 수막세포들로 구성되었으며, 세포 외부에 다양한 크기와 형태의 많은 낭포성 공간이 관찰되었다. 면역조직화학염색 결과 종양세포들은 vimentin 양성, 신경원 특이 에놀라제 및 신경교 섬유질 산성 단백질에는 음성을 나타내었다. 경수와 흉수 부위에는 부정형의 확장된 중심관 유사 동공이 관찰되었다. 이 증례는 개에서 특이적인 두개강 내 소낭성 뇌수막종과 연관되어 2차적으로 발생한 척수공동증의 임상소견과 영상학적 및 병리조직학적 특징을 보여주고 있다.

• Radiation Oncology Journal
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• 제4권2호
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• pp.107-113
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• 1986

방사선에 의한 척수의 손상은 매우 드물기는 하나 치명적인 불가역성의 손상을 일으킬 수 있는, 치료방사선 분야에서 가장 심각한 합병증의 하나이다. 동물실험 및 임상보고를 통하여 많은 연구가 있었음에도 실제의 임상에서와 같은 조사방법을 사용한 계통적인 보고는 거의 없는 실정이다. 이에 저자는 전 조사량에 대한 초기의 급성 변화를 병리조직학적으로 관찰 분석하여 불가역성의 척수손상이 올 수 있는 최저선량을 추정하기 위하여 250KV의 X선 치료기를 사용하여 총 110마리의 마우스를 $2\times3cm$의 조사야로 고식적 분할조사를 실시하였으며 그 결과는 다음과 같다. 경한 모세혈관의 울혈, 염증성 세포의 부분적 침윤과 함께 축색돌기의 부종이 1,000 rad 군에서 관찰되기 시작하였다. 백질의 스폰지 변성은 2,000 rad 군에서 보이기 시작하였다. 연막과 지주막의 부분적 비후는 3,000rad 군에서 관찰되었다. 국소 괴사는 3,500rad군에서 관찰되기 시작하였고 신경조직의 단열과 신경원의 국소 손실은 4,000 rad군에서 관찰되기 시작하였다. 이제까지 용인되어온 척수의 내성선량인 5,000 rad/5wk.는 완전히 안전하지는 못하다고 생각되나 이는 만성 변화에 대한 추적실험을 통하여 확인되어야 할 것이다.

• 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.