• Journal of Chest Surgery
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• 제33권8호
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• pp.605-612
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• 2000

Background: Ischemic preconditioning enhances the tolerance of myocardium against ischemia/reperfusion injury, with the enhancement of the recovery of post-ischemic myocardial function. This study was disigned to assess whether the protective effect of ischemic preconditioning could provide one additional hour of myocardial preservation in four hour myocardial ischemia in a rate heart. Material and method: Fourty four Spargue-Dawley rats, weighing 300~450gm, were divided into four groups. Group 1(n=7) and group 3(n=12) were subjected to 30 minutes of aerobic Langendorff perfusion without ischemic preconditioning and then preserved in saline solution at 2~4$^{\circ}C$ for 4 hours and 5 respectively. Group 2(n=7) and group 4(n=18) were perfused in the same way for 20 minutes, followed by 3 minutes of global mormothermic ischemia and 10 minutes of perfusion and then preserved in the same cold saline solution for 4 hours and 5 hours respectively. Heart rate, left ventricular developed pressure(LVDP), and coronary flow were measured at 15 minutes during perfusion as baseline. Spontaneous defibrillation time was measured after reperfusion. Heart rate, LVDP, and coronary flow were also recorded at 15 minutes, 30 minutes, and 45 minutes during reperfusion. Samples of the apical left ventricular wall were studied using a transmission electron microscope. Result: Time of spontaneous defibrillation(TSD) was significantly longer in group 4 than in group 1(p<0.001), and TSD in group 1 was significantly longer in comparision to that of group 2(p<0.05). Heart rate at 45 minutes was significantly higher in group 1 than in group 4(p<0.05). Heart rate at 15 min was significantly higher in group 2 than in group 1(p<0.001) and in group 4 than in group 3(p<0.05). Left ventricular developed pressure(LVDP) at 30 minutes and 45 minutes was higher in group 1 than in group 4(p<0.01), LVDP at 45 minutes was higher in group 4 than in group 3(p<0.05). Rate-pressure product(RPP) at 30 minutes and 45 minutes was higher in group 1 than in group 4(p<0.05). RPP at 15 minutes was higher in group 2 than in group 1(p<0.01). RPP at 30 minutes and 45 minutes was higher in group 4 than in group 3(p<0.05). Group 2 showed relatively less sarcoplasmic edema and less nuclear chromatin clearance than group 1. Group 4 showed less myocardial cell damage than group 3, group 4 showed less myocardial cell damage than group 3, group 4 showed more myocardial cell edema than group 1. Conclusion: Ischemic preconditioning enhanced the recovery of postischemic myocardial function after 4 hours and 5 hours preservation. However, it was not demonstrated that ischemic preconditioning could definitely provide one additional hour of myocardial preservation in four hour myocardial ischemia in a rat heart.

• The Korean Journal of Physiology and Pharmacology
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• 제8권4호
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• pp.207-211
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• 2004

The purpose of the present study was to evaluate the expression of cardiac marker protein in rabbit cardiac tissue that was exposed to ischemic preconditioning (IPC), or ischemiareperfusion injury (IR) using two-dimensional gel electrophoresis (2DE) and matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). We compared 2DE gels of control (uninjured) cardiac tissue with those of IPC and IR cardiac tissue. Expression of one protein was detected in IR heart tissue, however the protein was not detected in the samples of control and IPC tissue. To further characterize the detected protein molecule, the protein in the 2D gel was isolated and subjected to trypsin digestion, followed by MALDI-MS. The protein was identified as myoglobin, which was confirmed also by Western blot analysis. These results are consistent with previous studies of cardiac markers in ischemic hearts, indicating myoglobin as a suitable marker of myocardial injury. In addition, the present use of multiple techniques indicates that proteomic analysis is an appropriate means to identify cardiac markers in studies of IPC and IR.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.79.2-79.2
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• 2003

Minocycline is known to protect neurons from microglia-mediated cell death in many experimental models of brain diseases including ischemic stroke, Huntington's disease (HD), amyotrophic lateral sclerosis (ALS), traumatic brain injury, multiple sclerosis, and Parkinson's disease. Activation of caspase-2, 3, 8, and 9 was evident within 2-8 hr following oxidative insult with 0.5 mM hydrogen peroxide in PC12 cells. Minocycline significantly attenuated activation of these caspases up to 18 hr, resulting a significant increase in cell viability as assessed by MTT assay. (omitted)

• Neonatal Medicine
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• 제16권2호
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• pp.221-233
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• 2009

목 적 : 신장에서 분비되어 적혈구를 생산하는 빈혈제로 알려진 에리스로포이에틴(Erythropoietin, EPO)은 단순히 피를 만드는 조혈기능 뿐 아니라 최근 신경계 보호 및 신경강화 효과가 있다고 발표되고 있지만 주산기 가사로 인한 저산소성 허혈성 뇌병증의 치료제로서 그 기전이 명확하게 밝혀지지 않았다. 저자들은 유전자 재조합 인 에리스로포이에틴(recombinant Human EPO, rHuEPO)을 이용하여 주산기 저산소성 허혈성 뇌병증의 치료제로서 N-methyl-D-aspartate (NMDA) 수용체와 관련된 흥분성 독성작용을 통한 조절 등 그 기전을 알아보고자 하였다. 방 법 : 재태기간 19일된 태아 백서의 대뇌피질 세포를 배양하여 정상산소군은 5% $CO_2$ 배양기(95% air, 5% $CO_2$)에 두었고, 저산소군과 농도별 뇌손상 전 rHuEPO 투여군(1, 10, 100 IU/mL)은 1% $O_2$ 배양기(94% $N_2$, 5% $CO_2$)에서 6시간 동안 뇌세포손상을 유도하였다. 세포성장과 생존력을 평가하기 위해 MTT 실험을 시행하였다. 동물 모델에서는 생후 7일된 신생백서의 좌측 총 경동맥을 결찰한 후 6개 군; 정상산소군, sham-operated군, 저산소-허헐성군, 저산소-허헐성+vehicle군, 저산소-허헐성 손상 전 rHuEPO 투여군, 저산소-허헐성 손상 후 rHuEPO 투여군으로 나누었고, 저산소-허헐성 손상은 특별히 제작한 통속에서 2시간 동안 8% $O_2$ (8% $O_2$, 92% $N_2$)에 노출시켰다. rHuEPO은 뇌손상 전후 30분에 체중 kg당 1000 IU를 투여하였고, 저산소-허헐성 손상 후 7일째 조직을 실험하였다. 적출한 조직으로 H&E 염색을 하여 뇌손상을 형태학적으로 관찰하였다. 세포배양 및 동물실험에서 NMDA 수용체의 아단위인 NR1, NR2A, NR2B, NR2C, NR2D를 이용하여 실시간 중합효소연쇄반응을 실시하였다. 결 과 : 저산소군에서 세포 생존률은 정상산소군보다 60% 감소하였으며, rHuEPO 투여군(1, 10 IU/mL)은 80% 증가하였다. rHuEPO 투여군(100 IU/mL)은 회복되지 않았다. 우측 반구 대비 좌측 반구의 범위는 정상산소군 98.9%, sham-operated군 99.1%, 저산소-허헐성군 57.1%, 저산소-허헐성+vehicle군 57.0%, 저산소-허헐성 손상 전 rHuEPO 투여군 87.6%, 저산소-허헐성 손상 후 rHuEPO 투여군 91.6%으로 나타났다. NMDA 수용체의 아단위 생체외 실험에서 실시간 중합효소연쇄반응의 결과 NMDA 수용체 아단위 mRNA의 발현은 rHuEPO 투여군에서 저산소군보다 모두 증가하였다. 결 론 : 본 연구에서 rHuEPO은 흥분성 독성작용과 관련되어 NMDA 수용체를 조절하면서 저산소성 허헐성 뇌손상을 보호하는 것을 알 수 있었다.

• The Korean Journal of Physiology
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• 제30권2호
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• pp.289-297
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• 1996

Excitatory amino acids (EAA) are thought to play an important role in producing cell death associated with ischemic and traumatic spinal cord injury. The present study was carried out to determine if the response characteristics of spinal sensory neurons in segments adjacent to degeneration sites induced by EAA are altered following these morphological changes. Intraspinal injections of quisqualic acid (QA) produced neuronal degeneration and spinal cavitation of gray matter. The severity of lesions was significantly attenuated by pretreatment with a non-NMDA antagonist NBQX. In extracellular single unit recordings, dorsal horn neurons in QA injected animal showed the increased mechanosensitivity, which included a shift to the left in the stimulus-response relationship, an increased background activity and an increase in the duration of after-discharge responses. Neuronal responses, especially the C-fiber response, to suprathreshold electrical stimulation of sciatic nerve also increased in most cases. These results suggest that altered functional states of neurons may be responsible for sensory abnormalities, e.g. allodynia and hyperalgesia, associated with syringomyolia and spinal cord injury.

• Neonatal Medicine
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• 제17권2호
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• pp.168-180
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• 2010

Acute renal failure (ARF) is common in the neonatal period, however, there are no uniform treatment strategies of ARF. The main treatment strategies are conservative management including medical treatment and the renal replacement therapy. Because ARF in the newborn is commonly acquired by hypoxic ischemic injury and toxic insults, removal of all the offending causes is important. Aminoglycoside, indomethacin, and amphotericin-B are the most common nephrotoxic drugs of ARF. To relieve the possible prerenal ARF, initial fluid challenge can be followed by diuretics. If there is no response, fluid restriction and correction of electrolyte imbalance should begin. Adequate nutritional support and drug dosing according to the pharmacokinetics of such drugs will be difficult problems. Renal replacement therapies may be provided by peritoneal dialysis, intermittent hemodialysis, or hemofiltration. New promising agents, bioartificial kidney, and stem cell will enable us to extend our therapeutic repertoire.

• 대한화상학회지
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• 제23권1호
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• pp.13-19
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• 2020

Treatment of compartment syndrome is early decompressive fasciotomy to prevent dreadful sequelae of ischemic necrosis of muscles and nerves. We experienced one patient of impending or early compartment syndrome of right forearm and hand caused by a hot compress machine. We did immediate fasciotomy on forearm and late flap coverage with skin graft in this patient with good results.

• Preventive Nutrition and Food Science
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• 제17권3호
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• pp.177-183
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• 2012

Interruption of blood flow through coronary arteries and its subsequent restoration triggers the generation of a burst of reactive oxygen species (ROS), leading to myocardial cell death. In this study, we determined whether a methanol extract of Cassia mimosoides var. nomame Makino could prevent myocardial ischemia-reperfusion injury. When radical scavenging activity of the extract was measured in vitro using its ${\alpha}$,${\alpha}$-diphenyl-${\beta}$-picrylhydrazyl (DPPH) radical quenching ability, the extract showed an activity slightly lower than that of ascorbic acid. Three days after oral administration of the extract (400 mg/kg/day) to rats, myocardial ischemia/reperfusion injury was generated by 30 min of ligation of the left anterior descending coronary artery (LAD), followed by 3 hr reperfusion. Compared with the vehicle-treated group, administration of the extract significantly reduced infarct size (IS) (ratio of infarct area to area at risk) in the extract-treated group by 28.3%. Reduction in the cellular injury was mediated by attenuation of Bax/Bcl-2 ratio by 33.3%, inhibition of caspase-3 activation from procaspase-3 by 40%, and subsequent reduction in the number of apoptotic cells by 66.3%. These results suggest that the extract attenuates myocardial injury in a rat model of ischemia-reperfusion by scavenging ROS, including free radicals, and consequently blocking apoptotic cascades. Therefore, intake of Cassia mimosoides var. nomame Makino might be beneficial for preventing ischemic myocardial injury.

• Biomolecules & Therapeutics
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• 제25권4호
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• pp.383-389
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• 2017

Dexmedetomidine is an ${\alpha}2$-adrenergic receptor agonist that exhibits a protective effect on ischemia-reperfusion injury of the heart, kidney, and other organs. In the present study, we examined the neuroprotective action and potential mechanisms of dexmedetomidine against ischemia-reperfusion induced cerebral injury. Transient focal cerebral ischemia-reperfusion injury was induced in Sprague-Dawley rats by middle cerebral artery occlusion. After the ischemic insult, animals then received intravenous dexmedetomidine of $1{\mu}g/kg$ load dose, followed by $0.05{\mu}g/kg/min$ infusion for 2 h. After 24 h of reperfusion, neurological function, brain edema, and the morphology of the hippocampal CA1 region were evaluated. The levels and mRNA expressions of interleukin-$1{\beta}$, interleukin-6 and tumor nevrosis factor-${\alpha}$ as well as the protein expression of inducible nitric oxide synthase, cyclooxygenase-2, nuclear factor-${\kappa}Bp65$, inhibitor of ${\kappa}B{\alpha}$ and phosphorylated of ${\kappa}B{\alpha}$ in hippocampus were assessed. We found that dexmedetomidine reduced focal cerebral ischemia-reperfusion injury in rats by inhibiting the expression and release of inflammatory cytokines and mediators. Inhibition of the nuclear factor-${\kappa}B$ pathway may be a mechanism underlying the neuroprotective action of dexmedetomidine against focal cerebral I/R injury.

• Archives of Reconstructive Microsurgery
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• 제2권1호
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• pp.53-61
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• 1993

High level, major limb amputation above the wrist and ankle joint has some characteristic problems because of the large muscle mass and poor potential for nerve regeneration. As an adjunct method to reduce warm ischemic time prior to bony stabilization, temporary vascular shunting by simple catheterization has been performed, which has not been associated with any significant complication and has improved on success rate in replantation surgery. The authors have experienced 198 cases replantation of amputated limbs and digits from September, 1983 at the Korea medical center, Guro hospital, of which, 13 cases of successful replantation of amputated limbs by avulsion injury above the wrist and ankle joint level, which is generally considered as contraindication, were followed up for average 4.5 years(minimum 1.5 to maximum 8.4 years) on terms of survival rate, function and appearance. The clinical analysis upon these cases is to be presented with review of references.