흰쥐 간장에서 허혈/재관류로 인한 분비 기능 및 약물대사 변동

조준필,정윤석 대한응급의학회 1997 대한응급의학회지 Vol.8 No.4

Ischemia causes tissue necrosis in a wide variety of pathologic conditions. Permanent deprivation of blood flow is lethal to any tissue and the prudent therapy for ischemia unquestionably is reperfusion. While reperfusion is necessary to reverse the progression towards ischemic death, reperfusion is also thought to be accompanied by its own component of injury. Oxygen free radicals, formed during ischemia/reperfusion, have been proposed as one of main causes of reperfusion injury. Free radical attacks on biological membrane, such as mitochondria and endoplasmic reticulum, and can lead to the oxidative destruction of the polyunsaturated fatty acids of the membranes through lipid peroxidation. However, direct association between microsomal lipid peroxidation in vivo after ischemia/reperfusion and changes in secretory function and drug metabolism on the liver have not been established. Therefore, present study was performed to evaluate the hepatic secretory function and the hepatic microsomal drug metabolizing enzyme activity after ischemia/reperfusion preparation in rat liver. Further, the effect of oxygen free radical scavengers was investigated. The animals were divided into sham operation group and ischemia/reperfusion group. The ischemia/reperfusion group was subdivided into non-treated control and treated(with superoxide dismutase, allopurinol, α- tocopherol, deferoxamine)groups. Hepatic ischemia was produced by clamping the left branches of portal vein and hepatic artery, resulting in complete ischemia to the median and left lobes while the right lobes remained perfused to prevent intestinal congestion. Reperfusion was permitted by declamping after 1 hour. After 1 or 5 hours of reperfusion, bile was collected, blood was obtained from abdominal aorta, and liver microsomes were isolated. The results are as follows. Serum aminotransferase was increased 15-20 times by ischemia/reperfusion. However, this increase was attenuated by free radical scavengers, especially 5 hours of reperfusion. The wet weight-to9 dry weight ratio of the liver was significantly increased by ischemia/reperfusion. α- tocopherol pretreatment minimized the increase of ratio. Malondialdehyde level in the liver microsomal fraction was significantly increased after ischemia/reperfusion, but this increase was attenuated by scavenger pretreatment, especially α- tocopherol. Bile flow and cholate output, but not the bilirubin output, were decreased after ischemia/reperfusion. The free radical scavenger pretreatment restored the secretion significantly. Cytochrome P-450 content was significantly decreased after ischemia/reperfusion and ameliorated by free radical scavenger pretreatment. NADPH cytochrome p-450 reductase activity and aminopyrine N-demethylase activity were also decreased and improved by free radical scavengers pretreatment. These results indicate that ischemia/reperfusion deteriorates the hepatic secretory function as well as hepatic microsomal drug metabolizing enzyme activity, and the oxygen free radical scavengers the functional changes of the liver induced by ischemia/reperfusion.

Expression and Activity of the Na-K ATPase in Ischemic Injury of Primary Cultured Astrocytes

Kim, Mi Jung,Hur, Jinyoung,Ham, In-Hye,Yang, Hye Jin,Kim, Younghoon,Park, Seungjoon,Cho, Young-Wuk The Korean Society of Pharmacology 2013 The Korean Journal of Physiology & Pharmacology Vol.17 No.4

Astrocytes are reported to have critical functions in ischemic brain injury including protective effects against ischemia-induced neuronal dysfunction. Na-K ATPase maintains ionic gradients in astrocytes and is suggested as an indicator of ischemic injury in glial cells. Here, we examined the role of the Na-K ATPase in the pathologic process of ischemic injury of primary cultured astrocytes. Chemical ischemia was induced by sodium azide and glucose deprivation. Lactate dehydrogenase assays showed that the cytotoxic effect of chemical ischemia on astrocytes began to appear at 2 h of ischemia. The expression of Na-K ATPase ${\alpha}1$ subunit protein was increased at 2 h of chemical ischemia and was decreased at 6 h of ischemia, whereas the expression of ${\alpha}1$ subunit mRNA was not changed by chemical ischemia. Na-K ATPase activity was time-dependently decreased at 1, 3, and 6 h of chemical ischemia, whereas the enzyme activity was temporarily recovered to the control value at 2 h of chemical ischemia. Cytotoxicity at 2 h of chemical ischemia was significantly blocked by reoxygenation for 24 h following ischemia. Reoxygenation following chemical ischemia for 1 h significantly increased the activity of the Na-K ATPase, while reoxygenation following ischemia for 2 h slightly decreased the enzyme activity. These results suggest that the critical time for ischemia-induced cytotoxicity of astrocytes might be 2 h after the initiation of ischemic insult and that the increase in the expression and activity of the Na-K ATPase might play a protective role during ischemic injury of astrocytes.

Hypothyroid state does not protect but delays neuronal death in the hippocampal CA1 region following transient cerebral ischemia: Focus on oxidative stress and gliosis

Lee, Choong Hyun,Yoo, Ki-Yeon,Hwang, In Koo,Choi, Jung Hoon,Park, Ok Kyu,Li, Hua,Kang, Il-Jun,Kwon, Young-Guen,Kim, Young-Myeong,Won, Moo Ho Wiley Subscription Services, Inc., A Wiley Company 2010 Journal of neuroscience research Vol.88 No.12

<P>We investigated protective effects of hypothyroidism on delayed neuronal death, gliosis, lipid peroxidation and Cu,Zn-superoxide dismutase (SOD1) in the gerbil hippocampal CA1 region (CA1) after 5 min of transient cerebral ischemia. The hypothyroidism was induced by 0.025% methimazole treatment. Free triiodothyronine and thyroxine levels were markedly decreased in the hypothyroid group. Four days after ischemia/reperfusion, only a few NeuN-immunoreactive (+) neurons were detected in the CA1 of euthyroid-ischemia (eu-ischemia) group; however, at this time point, the number of NeuN<SUP>+</SUP> neurons was significantly higher in the hypothyroid-ischemia (hypo-ischemia) group than in the eu-ischemia group. At 5 days postischemia, NeuN<SUP>+</SUP> neurons were significantly decreased in the hypo-ischemia group: The number of NeuN<SUP>+</SUP> neurons in this group was similar to that in the eu-ischemia group. Activations of GFAP<SUP>+</SUP> astrocytes and Iba-1<SUP>+</SUP> microglia in the CA1 were higher in the eu-ischemia group 3 and 4 days after ischemia/reperfusion. At 5 days postischemia, the activations of both the glial cells in the CA1 were similar between the two groups. 4-Hydroxy-2-nonenal (HNE), a marker for lipid peroxidation, immunoreactivity in the eu-ischemia group was higher than in the hypo-ischemia group; at 5 days postischemia, the immunoreactivity was similar between the two groups. In contrast, SOD1 level was lower in the CA1 of the eu-ischemia group. These results suggest that hypothyroid state does not protect against delayed neuronal death but only delays the neuronal death in the hippocampal CA1 region after transient cerebral ischemia by reducing lipid peroxidation and increasing SOD1. © 2010 Wiley-Liss, Inc.</P>

Tadalafil이 뇌 허혈 유발 모래 쥐의 운동 피질에서 세포 사멸에 미치는 영향

고일규,김성은,김동현,김태운,김보균,신말순,김창주,나용길,주관중,김계환 대한남성과학회 2010 The World Journal of Men's Health Vol.28 No.1

Purpose: Cerebral ischemia leads to neuronal cell death, and eventually causes neurological impairments. Tadalafil is a long-acting phosphodiesterase type-5 (PDE-5) inhibitor, and it has been used for the treatment of erectile dysfunction. In the present study, we investigated whether tadalafil has the protective effect on apoptotic neuronal cell death in the motor cortex following transient global ischemia in gerbils. Materials and Methods: For this study, Mongolian gerbils were used for the experimental animals, and transient global ischemia was induced to the gerbils by occlusion of both common carotid arteries for 7 min. Gerbils were randomly divided into five groups (n=8 in each group): the sham-operation group, the cerebral ischemia-induced group, the cerebral ischemia-induced and 0.1 mg/kg tadalafil-treated group, the cerebral ischemia-induced and 1 mg/kg tadalafil-treated group, the cerebral ischemia-induced and 10 mg/kg tadalafil-treated group. Tadalafil-treated groups received tadalafil orally once a day for a 7 consecutive days, starting one day after surgery. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay and immunohistochemistry for caspase-3 were performed for the detection of apoptotic neuronal cell death in the motor cortex. Results: The number of TUNEL-positive cells was 21.45±3.69/section in the sham-operation group, 771.66± 97.25/section in the cerebral ischemia-induced group, 688.44±81.35/section in the cerebral ischemia- induced and 0.1 mg/kg tadalafil-treated group, 295.66±36.34/section in the cerebral ischemia-induced and 1 mg/kg tadalafil-treated group, and 198.47±25.25/section in the cerebral ischemia-induced and 10 mg/kg tadalafil-treated group. In the present results, induction of ischemic injury increased apoptotic neuronal cell death in the motor cortex of gerbils. However, tadalafil treatment suppressed the cerebral ischemia-induced apoptotic neuronal cell death in the motor cortex as dose-dependently. Conclusions: Here in this study, we showed that tadalafil has protective effect on the cerebral ischemia-induced apoptotic neuronal cell death, and thus this drug may facilitate the recovery following ischemic cerebral injury.

망막정맥폐쇄 환자에서 황반허혈과 최종시력과의 연관성

노광명,이지은,남기엽,이승욱,이상준,Gwang Myung Noh,Ji Eun Lee,Ki Yup Nam,Seung Uk Lee,Sang Joon Lee 대한안과학회 2014 대한안과학회지 Vol.55 No.10

Purpose: To identify the correlation between final visual outcome after at least 6 months of follow-up and the extent of macular ischemia on the first visit. Methods: We performed a retrospective clinical analysis of macular ischemia using clinical records, fundus examinations, and fluorescein angiographies in 83 patients (86 eyes) diagnosed with retinal vein occlusion from January 1998 to July 2012 and followed up for over 6 months. We evaluated the extent and the location of macular ischemia, macular edema, initial and final visual acuities and systemic disease based on fluorescein angiography and optical coherence tomography performed within 2 weeks of the first visit. The patients were divided into the following 4 groups based on the extent and location of macular ischemia and edema: superotemporal, superonasal, inferotemporal, and inferonasal. Results: Retinal vein occlusions (RVOs) consisted of 24 central RVOs (CRVOs) and 62 branch RVOs (BRVOs). Mean initial acuity (log MAR) was 0.35 ± 0.31 (36 eyes) in the no macular ischemia group, 0.40 ± 0.21 (11 eyes) in the 1-quadrant macular ischemia group, 0.71 ± 0.32 (26 eyes) in the 2-quadrant macular ischemia group and 0.73 ± 0.36 (13 eyes) in the over 3 quadrants macular ischemia group. Mean final acuity (log MAR) was 0.23 ± 0.23 in the no macular ischemia group, 0.40 ± 0.30 in the 1-quadrant macular ischemia group, 0.51 ± 0.32 in the 2-quadrant macular ischemic group and 0.73 ± 0.31 in the over 3 quadrants macular ischemia group. Conclusions: The initial and final visual outcomes were worse when more quadrants were affected by macular ischemia. The extent of macular ischemia was correlated with initial visual acuity and final visual outcome but not with macular edema. J Korean Ophthalmol Soc 2014;55(10):1493-1498

흰 쥐의 국소성 피질성 뇌경색 모델에서 관찰되는 유발전위의 변화

이성재,박원범,채상한,이영일,김태욱 대한재활의학회 2009 Annals of Rehabilitation Medicine Vol.33 No.2

Objective: To investigate the changes of motor and somatosensory evoked potentials found in focal cerebral cortical ischemia induced by endothelin-1 (ET-1), one of the common models of cerebral infarct in rats. Method: A total of twenty Sprague-Dawley rats were studied. Focal cerebral cortical ischemia was induced by steterotaxic injection of ET-1 into forelimb region of cerebral cortex. Pellet retrieval test, motor evoked potential (MEP), and somatosensory evoked potential (SEP) were compared before and after cerebral ischemia. The location and extent of cerebral ischemia were confirmed histologically. Results: Success rate of pellet retrieval test decreased significantly after induction of cerebral ischemia, demonstrating sensorimotor deficit in the contralateral forelimb. The latency and amplitude of MEP did not changed significantly despite weakness of forelimb. However, SEP showed reversal of the positive peaks. Conclusion: The results suggest that the changes of MEP and SEP in focal cerebral cortical ischemia are different from those in cerebral ischemia by large artery occlusion. When evaluating MEP and SEP in focal cerebral ischemia model, interpretation of evoked potentials should be cautious. Objective: To investigate the changes of motor and somatosensory evoked potentials found in focal cerebral cortical ischemia induced by endothelin-1 (ET-1), one of the common models of cerebral infarct in rats. Method: A total of twenty Sprague-Dawley rats were studied. Focal cerebral cortical ischemia was induced by steterotaxic injection of ET-1 into forelimb region of cerebral cortex. Pellet retrieval test, motor evoked potential (MEP), and somatosensory evoked potential (SEP) were compared before and after cerebral ischemia. The location and extent of cerebral ischemia were confirmed histologically. Results: Success rate of pellet retrieval test decreased significantly after induction of cerebral ischemia, demonstrating sensorimotor deficit in the contralateral forelimb. The latency and amplitude of MEP did not changed significantly despite weakness of forelimb. However, SEP showed reversal of the positive peaks. Conclusion: The results suggest that the changes of MEP and SEP in focal cerebral cortical ischemia are different from those in cerebral ischemia by large artery occlusion. When evaluating MEP and SEP in focal cerebral ischemia model, interpretation of evoked potentials should be cautious.

SOD, DMTU및 허혈양상화 처치가 허혈 및 재관류에 의한 흰쥐 넙다리곧은근의 미세구조 변화에 미치는 영향

백두진,임재현,정호삼,Paik, Doo-Jin,Lim, Jae-Hyun,Chung, Ho-Sam 한국현미경학회 1997 Applied microscopy Vol.27 No.3

The ischemia and reperfusion injury of the skeletal muscles is caused by generation of reactive oxygen during ischemia and reperfusion. It is well known that over 4 hours of ischemia injures the skeletal muscles irreversibly. The author has demonstrated the effects of SOD (superoxide dismutase), DMTU (dimethyl thiourea) and ischemic preconditioning on ultrastructural changes of the muscle fibers in the rectus femoris muscles after 4 hours of ischemia and 1 day and 3 days of reperfusion. A total of 72 healthy Sprague-Dawley rats weighing from 200 gm to 250 gm were used as experimental animals. Under urethane(1.15 g/kg, IP, 2 times) anesthesia, lower abdominal incision was done and the left common iliac artery was occluded by using vascular clamp for 4 hours. The left rectus femoris muscles were obtained at 1 and 3 days after the removal of vascular clamp. The SOD (15,000 unit/kg) or DMTU (500 mg/kg) were administered intraperitoneally at 1 hour before induction of ischemia. The ischemic preconditioned group underwent three episodes of 5 minutes occlusion and 5 minutes reperfusion followed by 4 hours of ischemia and 1 day and 3 days of reperfusion. The specimens were sliced into $1mm^3$ and prepared by routine methods for electron microscopic observation. All specimens were stained with uranyl acetate and lead citrate and then observed with Hitachi-600 transmission electron microscope. The results were as follows: 1. SOD or DMTU alone did not affect the ultrastructure of muscle fibers in the rectus femoris muscles. The electron density of mitochondrial matrix was decreased by ischemic preconditioning. 2. Dilated cisternae of sarcoplasmic reticulum, triad, mitochondria and the loss of myofilament in the sarcomere were observed in the 4 hours ischemia and 1 day reperfused rectus femoris muscles. Markedly changed sarcoplasmic reticulum, triad, disordered or loss of myofilament, indistinct A-band and I-band, and irregular electron lucent M -line and Z-line are seen in the 4 hours ischemia and 3 days reperfused rectus femoris muscles. 3. SOD reduced the changes of organelles in the muscle fibers of the 4 hours ischemia and 1 day reperfused rectus femoris muscles of the rats, but SOD did not affect the changes of muscle fibers in the 4 hours ischemia and 3 days reperfused muscles. On the other hand, DMTU markedly attenuated considerably the ultrastructural change of the 4 hours ischemia and 1 day or 3 days reperfused rectus femoris muscles. 4. By the ischemic preconditioning, the change was attenuated remarkably in the 4 hours ischemia and 1 day reperfused rectus femoris muscles. As the ischemic reperfused changes of muscle fibers were regenerated or recovered by ischemic preconditioning, the ultrastructures of them were similar to those of normal control in the 4 hours ischemia and 3 days reperfused rectus formoris muscles. Consequently, it is suggested that DMTU is stronger inhibitor to ischemic reperfused change than SOD. The ischemia and reperfusion-induced muscular damage is remarkably inhibited by ischemic preconditioning.

Expression and Activity of the Na-K ATPase in Ischemic Injury of Primary Cultured Astrocytes

김미정,허진영,함인혜,양혜진,김영훈,박승준,조영욱 대한약리학회 2013 The Korean Journal of Physiology & Pharmacology Vol.17 No.4

Astrocytes are reported to have critical functions in ischemic brain injury including protective effects against ischemia-induced neuronal dysfunction. Na-K ATPase maintains ionic gradients in astrocytes and is suggested as an indicator of ischemic injury in glial cells. Here, we examined the role of the Na-K ATPase in the pathologic process of ischemic injury of primary cultured astrocytes. Chemical ischemia was induced by sodium azide and glucose deprivation. Lactate dehydrogenase assays showed that the cytotoxic effect of chemical ischemia on astrocytes began to appear at 2 h of ischemia. The expression of Na-K ATPase α1 subunit protein was increased at 2 h of chemical ischemia and was decreased at 6 h of ischemia, whereas the expression of α1 subunit mRNA was not changed by chemical ischemia. Na-K ATPase activity was time-dependently decreased at 1, 3, and 6 h of chemical ischemia, whereas the enzyme activity was temporarily recovered to the control value at 2 h of chemical ischemia. Cytotoxicity at 2 h of chemical ischemia was significantly blocked by reoxygenation for 24h following ischemia. Reoxygenation following chemical ischemia for 1 h significantly increased the activity of the Na-K ATPase, while reoxygenation following ischemia for 2 h slightly decreased the enzyme activity. These results suggest that the critical time for ischemia-induced cytotoxicity of astrocytes might be 2 h after the initiation of ischemic insult and that the increase in the expression and activity of the Na-K ATPase might play a protective role during ischemic injury of astrocytes.

해인탕이 뇌허혈 유발 모래쥐의 단기기억력 감퇴와 치상회 세포사멸에 미치는 효과

박정철 ( Jung Chul Park ),송윤경 ( Yun Kyung Song ),임형호 ( Hyung Ho Lim ) 한방재활의학과학회 2011 한방재활의학과학회지 Vol.21 No.2

Objectives: We investigated the effect of Haein-tang(Hairen-tang) on short-term memory and apoptosis in dentate gyrus of the gerbils with transient global ischemia. Methods: For the induction of cerebral ischemia model in mice, common carotid arteries of gerbils were occluded with aneurysm clips for 5 min. One day after operation, Haein-tang(Hairen-tang) was administrated orally injected once a day for 15 consecutive days. Gerbils were randomly divided into four groups(n=10 in each group): sham-operation group, ischemia-induction group, ischemia-induction and 50 mg/kg Haein-tang(Hairen-tang)-treated group, ischemia-induction and 100 mg/kg Haein-tang(Hairen-tang)-treated group, and ischemia-induction and 200 mg/kg Haein-tang(Hairen-tang)-treated group. The effect of Haein-tang(Hairen-tang) on memory function was investigated by using step-down avoidance task. Apoptosis was confirmed by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling(TUNEL) staining and immunohistochemistry for caspase-3. Western blot analysis for the expressions of Bax and Bcl-2 protein was also conducted. Results: 1. Haein-tang extract significantly enhanced short-term memory in step-down avoidance task and 100 mg/kg, 200 mg/kg Haein-tang-treated group. 2. Haein-tang extract significantly suppressed TUNEL-positive cells after transient global ischemia and 50 mg/kg, 100 mg/kg, 200 mg/kg Haein-tang-treated group. 3. Haein-tang extract significantly increased caspase-3 positive cells in the hippocampal dentate gyrus after transient global ischemia and 50 mg/kg, 100 mg/kg, 200 mg/kg Haein-tang-treated group. 4. Haein-tang extract significantly decreased Bax protein expressions in the hippocampus after transient global ischemia and 100 mg/kg, 200 mg/kg Haein-tang-treated group. Haein-tang extract significantly increased Bcl-2 protein expressions in the hippocampal dentate gyrus after transient global ischemia and 50 mg/kg, 100 mg/kg, 200 mg/kg Haein-tang-treated group. Haein-tang extract significantly decreased Ratio of Bax protein to Bcl-2 protein in the hippocampus after transient global ischemia and 100 mg/kg, 200 mg/kg Haein-tang-treated group. Conclusions: While Haein-tang(Hairen-tang) treatment improved short-term memory by suppressing on ischemia-induction apoptosis. In the present study, Haein-tang (Hairen-tang) shows protective effect on transient global ischemia.

Ischemic preconditioning protects neurons from damage and maintains the immunoreactivity of kynurenic acid in the gerbil hippocampal CA1 region following transient cerebral ischemia

LEE, JAE-CHUL,TAE, HYUN-JIN,CHO, GEUM-SIL,KIM, IN HYE,AHN, JI HYEON,PARK, JOON HA,CHEN, BAI HUI,CHO, JEONG-HWI,SHIN, BICH NA,CHO, JUN HWI,BAE, EUN JOO,PARK, JINSEU,KIM, YOUNG-MYEONG,CHOI, SOO YOUNG,WO D.A. Spandidos 2015 INTERNATIONAL JOURNAL OF MOLECULAR MEDICINE Vol.35 No.6

<P>Pyramidal neurons in region I of hippocampus proper (CA1) are particularly vulnerable to excitotoxic processes following transient forebrain ischemia. Kynurenic acid (KYNA) is a small molecule derived from tryptophan when this amino acid is metabolized through the kynurenine pathway. In the present study, we examined the effects of ischemic preconditioning (IPC) on the immunoreactivity and protein levels of KYNA following 5 min of transient forebrain ischemia in gerbils. The animals were randomly assigned to 4 groups (sham-operated group, ischemia-operated group, IPC + sham-operated group and IPC + ischemia-operated group). IPC was induced by subjecting the gerbils to 2 min of ischemia followed by 1 day of recovery. In the ischemia-operated group, we observed a significant loss of pyramidal neurons in the CA1 stratum pyramidale (SP) at 5 days post-ischemia; however, in the IPC + ischemia-operated group, the pyramidal neurons were well protected. KYNA immunoreactivity in the SP of the ischemia-operated group was significantly altered following ischemia-reperfusion and was very low 5 days following ischemia-reperfusion. In the IPC + ischemia-operated group, however, KYNA immunoreactivity was constitutively detected in the SP of the CA1 region after the ischemic insult. We also found that the alteration pattern of the KYNA protein level in the CA1 region following ischemia was generally similar to the immunohistochemical changes observed. In brief, our findings demonstrated that IPC maintained and even increased KYNA immunoreactivity in the SP of the CA1 region following ischemia-reperfusion. The data from the present study thus indicate that the enhancement of KYNA expression by IPC may be necessary for neuronal survival following transient ischemic injury.</P>