• Archives of Reconstructive Microsurgery
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• 제14권2호
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• pp.85-94
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• 2005

Purpose: This study was to evaluate the effect of ${\alpha}-lipoic$ acid, a potent free radical scavenger, on the expression of active form of extracellular signal-regulated kinase (pERK1/2) proteins from hindlimb muscles of rats following ischemia-reperfusion injury. Material and methods: 64 health, $280{\sim}350\;g$ weighted Sprague-Dawley male rats were used. In order to make a muscle flap, the gastrocnemius (GC) and soleus (SOL) muscles were dissected and elevated. The popliteal artery was occluded for 4hours and reperfused for 10 minutes, 30 minutes, 1 hour, 2 hours and 4 hours, respectively. Results: The ischemia by occlusion of the popliteal artery itself caused a minimal change in expression of phosphorylated form of proteins observed in hindlimb muscle. In contrast, after 4 hours of ischemia, immunoreactivity for pERK1/2 in the GC muscle showed dual peaks at 10 minutes and 4 hours after reperfusion. In ${\alpha}-lipoic$ acid treated group, the expression of pERK1/2 was increased significantly compared to I/R-only group. Conclusion: These results suggest that ${\alpha}-lipoic$ acid may protect I/R injury of the skeletal muscle through free radical scavening and activation of intracellular pERK1/2 expression.

• Journal of Korean Neurosurgical Society
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• 제38권3호
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• pp.221-226
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• 2005

Objective : Reactive oxygen metabolites and polymorphonuclear leukocytes have been implicated in the pathophysiology of reperfusion injury. The mechanisms involved in superoxide-mediated leukocyte adherence remain unclear, however, nitric oxide[NO] may contribute to this response. The present study is undertaken to elucidate mechamisms controlling NO based mechanisms that regulated leukocyte-endothelial interactions in the cerebral vasculature after global cerebral ischemia and reperfusion. Methods : Pial venular leukocyte adherence of anesthetized newborn piglets was quantified by in situ fluorescence videomicroscopy through closed cranial windows during basal conditions and during 2hours of reperfusion after global ischemia induced by 9minutes of asphyxia. Nitric oxide synthase[NOS] was inhibited by local window superfusion of L-nitroarginine[NA]; superfusion of sodium nitroprusside[SNP] was used to donate NO. Results : The mean number of adherent leukocytes to cerebral venules in the 9minutes asphyxia and 2hours reperfusion group were $161{\pm}19$ compared with $13{\pm}4$ in the nonasphyxial group. Superfusion of L-NA through the cranial window for 2hours resulted in leukocyte adherence similar to that observed during the initial 2hours of reperfusion after asphyxia. Leukocyte adherence was not additionally increased in asphyxic animal treated with L-NA. SNP inhibited asphyxia induced leukocyte adherence back to control levels. Conclusions : Nitric oxide inhibits leukocyte adherence to cerebral venules during the initial hours of reperfusion after asphyxia, and that NO supplementation inhibit asphyxia induced leukocyte adherence back to control levels. These results indicate that NO is an important factor in ischemia-reperfusion induced leukocyte adherence.

• 대한중풍순환신경학회지
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• 제10권1호
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• pp.8-19
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• 2009

Scutellaria Radix, originated from Scutellaria baicalensis Georgi, is one of the most important medicine in traditional Oriental medicine, and possesses anti-bacterial activity and sedative effects, can be applied in the treatment of a range of conditions including diarrhea and hepatitis. It is reported that chronic global ischemia induces neuronal damage in selective, vulnerable regions of the brain, especially the hippocampus and cerebral cortex. In the present study, to investigate the effect of Scutellaria Radix extract on cerebral disease, the changes of regional cerebral blood flow and pial arterial diameter on ischemia/reperfusion state was determinated by Laser-Doppler Flowmetry and some parameters concerned with oxidative stress also measured. When SRe were administered for five days with the concentration of 100 mg/kg, GSH activity significantly increased. But SRe administeration showed no significant change in lipid peroxidation. When the activities of CAT, Cu, Zn-SOD and GSH were measured, CAT and GSH were activated by SRe administration. When 1 and 3 ㎍/㎖ SRe was applied to the neuronal cell cultures, the quantities of LDH was significantly reduced when compared with cultures treated only with NMDA. Through this study, it can be concluded that the ischemia/reperfusion induced brain stress may have contributed to cerebral damage in rats, and the present study provides clear evidence for the beneficial effect of SRe on ischemia induced brain injury.

• Applied Microscopy
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• 제22권1호
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• pp.42-54
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• 1992

To understand the structural changes of the myocardial myocytes and endothelial cells in ischemic and reperfused heart, and to elucidate their roles in those conditions, the authors observed cat and rat myocardium ultrastructurally and evaluated them with morphometric techniques. In cat, mild ischemia and moderate degree reperfusion injury was induced by ligation of the anterior interventricular branch of left coronary artery and reperfusion. In rat, severe ischemia and irreversible reperfusion iniury was made using in vitro Langendorff techniques. In normal cat myocytes, the volume densities of cytoplasm, myofibrils, mitochondria, sarcoplasmic reticulum and T tubules were $0.11{\pm}0.013,\;0.51{\pm}0.096,\;0.25{\pm}0.082,\;0.09{\pm}0.008,\;0.02{\pm}0.010$ (Mean${\pm}$S.D.) respectively, and the myofibril/mitochondria ratio was $2.33{\pm}1.379$. The numerical density and average volume of mitochondria were $0.76{\pm}0.210/{\mu}m^3$ and $0.33{\pm}0.057{\mu}m^3$ respectively. In normal cat endothelial cells, the volume densities of cytoplasm, cytoplasmic vesicles, tubular systems (including endoplasmic reticulum and Golgi apparatus) and mitochondria were $0.43{\pm}0.023,\;0.28{\pm}0.007,\;0.22{\pm}0.021,\;0.03{\pm}0.014$ respectively. The mean thickness of endothelial cells was $230{\pm}45.2{\mu}m$. The numerical density and average volume of cytoplasmic vesicles were $508{\pm}55.0/{\mu}m^3,\;578{\pm}104.8nm^3$ respectively. In cat myocytes which received mild ischemic injury, the volume densities of organelles were not changed significantly in ischemic and reperfusion states. In reperfusion group myocytes, the numerical density of mitochondria was decreased significantly and the average volume was increased significantly. In endothelial cells, the volume density of tubular system in ischemic group and the average volume of cytoplasmic vesicles in reperfusion group were increased significantly. In rat myocytes which received severe ischemic injury, the volume density and average volume of mitochondria were increased significantly, and the volume density of sarcoplasmic reticulum and numerical density of mitochondria were decreased significantly in both ischemic and reperfusion groups. In ischemic and reperfused endothelial cells, the volume density and numerical density of cytoplasmic vesicles, the volume density of cytoplasm were decreased significantly. The volume densities of tubular system were increased significantly in both ischemic and reperfused groups. The volume density of mitochondria in ischemic group and the average volume of cytoplasmic vesicles in reperfusion group showed significant increase. The authors, based on the above observations, conclude that the mitochondria of myocytes and the cytoplasmic vesicles of endothelia are the first group of targets in ischemic and reperfusion injury and in this respect, the degree of ischemic insult is not significant. The role of myocyte mitochondria in reperfusion injury may be insignificant, but endothelial cells may contribute actively to reperfusion injury.

• Journal of Ginseng Research
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• 제33권4호
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• pp.268-277
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• 2009

Ginsenosides are among the most well-known traditional herbal medicines frequently used for the treatment of cardiovascular symptoms in South Korea. The anti-ischemic effects of compound K (CK), a metabolite of ginsenoside Rb1, on ischemia-induced isolated rat hearts were investigated through the analyses of the changes in the hemodynamics (blood pressure, aortic flow, coronary flow, and cardiac output) and the measurement of the infarct region. The subjects in this study were divided into four groups: the normal control, the CK-alone group, the ischemia-induced group without any treatment, and the ischemia-induced group treated with CK. No significant differences in perfusion pressure, aortic flow, coronary flow, and cardiac output were found between the groups before ischemia was induced. The oxygen and buffer supply was stopped for 30 min to induce ischemia 60 min after reperfusion in the isolated rat hearts, and the CK was administered 5 min before ischemia induction. The CK treatment significantly prevented decreases in perfusion pressure, aortic flow, coronary flow, and cardiac output under ischemic conditions. In addition, the hemodynamics (except for the heart rate) of the group treated with CK significantly recovered 60 min after reperfusion, unlike in the control group. CK significantly limited the infarct. These results suggest that CK treatment has distinct anti-ischemic effects in an exvivo model of an ischemia-reperfusion-induced rat heart.

• 한국임상수의학회지
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• 제25권4호
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• pp.257-262
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• 2008

신장의 허혈-재관류 손상은 수술하는 동안 부득이하게 발생하는 허혈-재관류 손상에 대한 이식조직의 내성에 따라 이식된 장기의 생존력이 달려있기 때문에 임상적으로 아주 중요하다. 본 연구의 목적은 신장 혈관을 차단하여 유발한 허혈-재관류 모델에서 관류-흡인의 효과를 알아보고자 실시하였다. 신기능과 항산화 효소를 검사하기 위해 혈액 샘플을 채취하였고 신장내 동맥의 혈류저항을 측정하였다. 14일째 신장을 절제하여 조직검사를 실시하였다. 신기능(Cr, BUN)은 처치군에 비해 비처치군에서 유의성 있는 상승을 보였다. 신장내 혈류 저항은 두 그룹 사이에 유의성이 없었다. 항산화 효소 활성은 대조군에 비해 비처치군에서 유의성 있는 감소를 보였으나, 처치군에서는 대조군과 유의성이 없었다. 조직검사 결과에서도 처치군이 비처치군에 비해 적은 조직손상을 보였다. 이러한 결과는 관류-흡인 과정이 신장의 허혈-재관류 손상을 감소시키는데 유용한 단계임을 시사한다.

• 대한임상검사과학회지
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• 제51권3호
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• pp.370-378
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• 2019

허혈 재관류 손상은 기관 이식, 외과적 혈관 재개통 및 출혈시에 발생하며 조직 및 기관 기능 장애를 유발한다. 최근 허혈 재관류 손상의 기전적 연구를 위해 간장 허혈 모델을 많이 이용하고 있다. 본 연구는 허혈 재관류 랫드 모델을 이용하여 항산화와 항염증 효과를 가진 것으로 알려진 Vanillin에 의한 간장 및 신장 손상에 대한 보호 효과를 알아보고 관련된 기전을 조사하기 위하여 실시하였다. 시험물질은 각각 100 mg/kg의 농도로 3일간 투여한 후, 60분동안 간을 결찰하여 허혈 재관류를 유도하여 관찰하였으며, 음성대조군, sham대조군 및 허혈재관류만 실시한 허혈 재관류대조군을 따로 두어, 약물투여군과 비교하였다. Vanillin 처치군에서는 AST, ALT 활성이 허혈 재관류대조군에 비해 유의하게 억제되었고, 조직병리학적 관찰에서도 염증 부분과 괴사부분이 현저하게 감소하였다. MDA와 SOD는 허혈 재관류군에 비해 유의적인 변화를 보였다. 이상의 결과를 종합하면 Vanillin은 간장 허혈 재관류에 의한 세포염증 및 세포괴사를 완화시켜 간세포 보호작용을 나타내었고, 신장의 사구체 및 원위세뇨관에 염증 변화를 완화 시키고 있어 세포 손상을 방어하는 것으로 생각되며, 이러한 방어효과는 항산화 기능에 의한 영향으로 사료된다.

• 한국임상수의학회지
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• 제26권5호
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• pp.441-444
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• 2009

허혈/재관류 손상은 장기이식 분야에서 해결해야 할 주요 문제점으로 알려져 있다. 본 연구에서는 대퇴 동,정맥 부위에서 기존의 혈관 문합법 대신 맥관 connector를 이용하여 간단하면서 효과적인 체외 재관류 모델을 개발하였기에 소개하고자 한다. 개발된 모델이 허혈/재관류 손상연구에 효과적인지 알아보기 위해 혈액 동력학적 평가와 신장의 재관류 후 손상 양상을 분석하였다. 기존의 재관류 모델에서 사용되는 문합 부위인 복강 대동맥의 혈압과 본 연구에서 재관류 부위로 활용된 대퇴동맥의 혈압은 유의적 차이가 없었다. 허혈 손상 후 재관류 효과를 알아보기 위해 미니돼지에서 적출한 신장을 HTK 용액에 24, 48시간 동안 각각 저온보관 후 대퇴부에 이식하여 재관류 한 결과, 신장의 재관류까지 수술시간은 평균 $7.0{\pm}1.1$분 소요되었으며, 3시간 재관류 후 재관류 손상 정도는 저온보관시간에 따라 증가되는 것이 확인되었다. 이는 개발된 모델이 맥관 문합 없이 간단한 관류방법이면서도 기존의 복잡한 수술에 의한 재관류 방법과 유사한 손상 모델을 만들 수 있는 효과적인 허혈/재관류 동물모델이라는 것을 의미한다. 따라서 본 연구에서 개발한 신장 재관류 모델은 초기 허혈/재관류 손상 연구와 장기이식에서 이식면역연구에 효과적인 모델이라 사료된다.

• The Korean Journal of Physiology and Pharmacology
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• 제13권3호
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• pp.181-187
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• 2009

Intestinal ischemia/reperfusion (I/R) is one of common causes of acute lung injury (ALI). Early and accurate diagnosis of patients who are like to develop serious acute respiratory distress syndrome (ARDS) would give a therapeutic advantage. Ferritin and heme oxygenase-1 (HO-1) are increased by oxidative stress and are potential candidates as a predictive biomarker of ARDS. However, the mechanisms responsible for the increases of ferritin and HO-1, and their relationship to ALI, are unclear. In order to elucidate the interactions between ferritin and HO-1, we studied the changes in ferritin and HO-1 levels in serum and bronchoalveolar lavage (BAL) fluid after intestinal I/R injury in rats. Leukocyte number and protein contents in BAL fluid were elevated following I/R, and the increases were attenuated by mepacrine pretreatment. Both serum ferritin and HO-1 concentrations were progressively elevated throughout the 3 h observation period. Mepacrine pretreatment attenuated the increase of serum and BAL fluid ferritin concentrations, but did not suppress the increase of serum HO-1. Moreover, BAL fluid HO-1 levels did not change after I/R or after mepacrine pretreated I/R compared with sham rats. Unlike ferritin, HO-1 levels are not exactly matched with the ALI. Therefore, there might be a different mechanism between the changes of ferritin and HO-1 in intestinal I/R-induced ALI model.

• The Korean Journal of Physiology and Pharmacology
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• 제10권4호
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• pp.187-191
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• 2006

Serum ferritin levels are increased in subjects at-risk for or with acute lung injury (ALI), and there are observations to suggest that increases in serum ferritin levels may help predict the development of ALI in at-risk individuals. To deepen our understanding of increases of serum ferritin and their relationship to the development of ALI, we measured serum ferritin levels before and after intestinal ischemia/reperfusion (I/R) injury in rats, and found that serum ferritin levels increased significantly following I/R. Increases in serum and lavage ferritin levels paralleled increases in lung inflammation (lavage leukocyte numbers and tissue myeloperoxidase activities) and lung leak (lavage protein levels). In contrast, pre-treatment of rats with mepacrine (60 mg/kg, i.p.), a phospholipase $A_2$ inhibitor, attenuated not only I/R-induced serum and lavage ferritin increases, but also the development of ALI. These findings indicate that, besides of human subjects with ALI, serum ferritin levels increase early on also in an animal model of ALI. Therefore, serum and lavage ferritin can be a candidate for early biomarker of ALI.