• Title/Summary/Keyword: delayed neuronal death

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Changes of Polyamine Metabolism and Delayed Neuronal Degeneration of Hippocampus after Transient Cerebral Ischemia in Mongolian Gerbils (뇌허혈 손상에 있어서 Polyamine 대사의 변동이 해마신경세포의 지연성괴사에 미치는 효과에 관한 연구)

  • Shin, Kyung-Ho;Shin, Hwa-Jung;Lee, Young-Jae;Kim, Hyung-Gun;Choi, Sang-Hyun;Chun, Yeon-Sook;Chun, Boe-Gwun
    • The Korean Journal of Pharmacology
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    • v.32 no.3
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    • pp.323-334
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    • 1996
  • Male Mongolian gerbils $(60{\sim}80g)$ were given DL-difluoromethylornithine (DFMO; 250mg/kg, ip) and methylglyoxal bis(guanylhydrazone) (MGBG; 50 mg/k, ip), respectively, 1 h prior to transient (7 min) occlusion of bilateral common carotid arteries (OBC7) and a daily dose of one of them for 6 days after recirculation, and the polyamine contents, activities of ornithine and S-adenosylmethionine decarboxylases (ODC and SAM-DC), and light microscopic findings of the hippocampus were evaluated. The hippocampal putrescine (PT) levels of the control gerbils treated with saline (STGr), markedly increased after OBC7, showing a peak level at 24 h after recirculation. The peak PT level was reduced in DFMO treated gerbils (DTCr) and in MGBG treated gerbils (MTGr). And 7 days after recirculation, the PT level of DTGr was decreased to about 75% of the PT level in the sham operated group (nonTGr) and to about 55% of the STGr level, respectively. The hippocampal spermidine (SD) level of STGr tended to decline, showing the lowest value at 8 h after recirculation. But the spermidine (SD) level of DTGr was somewhat higher at 8 h after OBC7 than those of STGr and MTGr The hippocampal spermine (SM) levels of all the experimental groups were little changed for 7 days after OBC. OBC7 markedly increased the hippocampal ODC activity. reaching a maximum (about 3 times higher than preischemic level) at 8 h and rapidly recovered to the control value by 24 h in STGr gerbils, and the OBC7-induced increase of ODC activity was significantly attenuated by DFMO or MGBG treatment. Whereas OBC7 induced a rapid decrease of the hippocampal SAMDC activity follwed by gradual recovery to the preischemic level, and the decrease of the SAMDC activity was slightly attenuated by DFMO or MGBG treatment. 7 Days after OBC7 the histological finding of the hippocampal complex stained with cresyl violet showed an extensive delayed neuronal damage in the CA1 region and to a lesser extent, in the dentate gyrus, sparing the CA3 region. And the neuronal death was aggevated by DFMO but significantly attenuated by MGBG. The immunochemical reactivity of hippocampus to anti-GFAP antibody was significantly increased in the CA1 region and to a lesser extent, in the dentate gyrus 7 days after OBC7, but was little changed in the CA3. And the increase of the anti-GFAP immunoreactivity was moderately enhanced by DFMO and significantly suppressed by MGBG. These results suggest that the polyamine metabolism may play a modulatory role in the ischemic brain damage.

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Neuroprotective effect of lithium after pilocarpine-induced status epilepticus in mice

  • Hong, Namgue;Choi, Yun-Sik;Kim, Seong Yun;Kim, Hee Jung
    • The Korean Journal of Physiology and Pharmacology
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    • v.21 no.1
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    • pp.125-131
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    • 2017
  • Status epilepticus is the most common serious neurological condition triggered by abnormal electrical activity, leading to severe and widespread cell loss in the brain. Lithium has been one of the main drugs used for the treatment of bipolar disorder for decades, and its anticonvulsant and neuroprotective properties have been described in several neurological disease models. However, the therapeutic mechanisms underlying lithium's actions remain poorly understood. The muscarinic receptor agonist pilocarpine is used to induce status epilepticus, which is followed by hippocampal damage. The present study was designed to investigate the effects of lithium post-treatment on seizure susceptibility and hippocampal neuropathological changes following pilocarpine-induced status epilepticus. Status epilepticus was induced by administration of pilocarpine hydrochloride (320 mg/kg, i.p.) in C57BL/6 mice at 8 weeks of age. Lithium (80 mg/kg, i.p.) was administered 15 minutes after the pilocarpine injection. After the lithium injection, status epilepticus onset time and mortality were recorded. Lithium significantly delayed the onset time of status epilepticus and reduced mortality compared to the vehicle-treated group. Moreover, lithium effectively blocked pilocarpine-induced neuronal death in the hippocampus as estimated by cresyl violet and Fluoro-Jade B staining. However, lithium did not reduce glial activation following pilocarpine-induced status epilepticus. These results suggest that lithium has a neuroprotective effect and would be useful in the treatment of neurological disorders, in particular status epilepticus.

Effects of Woohwangcheongsim-won on Gene Expression in a Hypoxic Model of Cultured Rat Cortical Cells (배양한 흰쥐 대뇌세포의 저산소증 모델에서 우황청심원이 유전자 표현에 미치는 영향)

  • Park Dong-Wan;Kim Wan-Sik;Bae Cheol-hwan;Jeong Sung-Hyun;Shin Gil-Cho;Lee Won-Chul
    • The Journal of Korean Medicine
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    • v.25 no.3
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    • pp.123-136
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    • 2004
  • Objectives : The purpose of this investigation is to evaluate the effects of Woohwangcheongsim-won (WC) on the in vitro neuronal development and alteration in gene expression in a hypoxia model using cultured rat cortical cells. Methods : E/sub 18/ rat cortical cells were grown in a neurobasal medium containing B27 supplement and various concentration of WC. Initial development of growth cone was investigated by phase-contrast microscopy, while dendritic spine formation and synaptogenesis were investigated by immunocytochemistry with SynGAPα(a postsynaptic marker) and synaptophysin (presynaptic marker) antibodies. Alteration in gene expression was analyses by microarray using rat 5K-TwinChips. Results : WC suppressed the development of growth cones and WC increased the number of dendritic spines at 20 and 50㎍/mL concentration but there was no statistical significance. Instead, it significantly decreased the number at 100㎍/mL. The expression of anti-apoptosis gene Bcl2-like 1 (Bcl211) increased (Global M=0.46), while Akt1 decreased. Proapoptosis genes Bad and PDCD2 increased. The expression of hemoglobin alpha 1 (probably neuroglobin) increased (Global M=0.93). The expression of antioxidants such as catalase, heme oxygenase (HO), and PRKAG2 gene increased. The expression PKC gene increased. The expression of retinoic acid receptor alpha (RARα) increased significantly (Global M=1.0). Conclusions : These data suggest that WC trends to suppress cellular activity slightly in normoxia and increases the expression of apoptosis-, antioxidation-, oxygen capture-related genes in hypoxia, but increases Bcl111 that anti-apoptosis gene, on the other hand increases Bad, PDCD2 that pro-apoptosis genes, too..

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Histological changes on pyramidal layer of hippocampus following transient cerebral ischemia in gerbils (일시적 대뇌허혈에 의한 gerbil 해마의 피라밋층에 조직학적 변화)

  • Yang, Je-hoon;Koh, Phil-ok;Kwak, Soo-dong
    • Korean Journal of Veterinary Research
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    • v.41 no.4
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    • pp.467-475
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    • 2001
  • Cardiac arrest, hypoxia, shock or seizure has been known to induce cerebral ischemia. This study was designed to investigate the effect of ischemia on hippocampal pyramidal layer induced by transient bilateral occlusion of the common carotid arteries. Mature Mongolian gerbils were sacrificed at days 2, 4, and 7 after carotid occlusion for 10 minutes. Sham-operated gerbils of control group were subjected to the same protocol except for carotid occlusion. During operation for ischemia, body temperature was maintained $37{\pm}0.5^{\circ}C$ in all gerbils. Paraffin-embedded brain tissue blocks were cut into coronal slices and stained with H-E stain or immunostain by TUNEL method. Neurons with the oval and prominent nucleus and without the eosinophilic cytoplasm in the subfield of hippocamapal pyramidal layer were calculated as to be viable neurons. Their chromatins were condensed or clumped. Their nuclei appeared multiangular or irregularly shrinked. The width of the pyramidal layer was reduced due to the loss of nuclei. At day 2 after reperfusion, some neurons in the CA1 subfield were slightly eosinophilic. But most neurons in the CA2 subfield were strongly eosinophilic. At day 4 day, most neurons in the CA1 subfield were severely damaged and at day 7 day, only a few survived neurons were observed. Survived neurons per longitudinal 1mm sector in the CA1, CA2, CA3, and CA4 subfields of pyramidal layer were investigated. At day 2, the mean numbers of pyramidal neurons in CA1, CA2, CA3, and CA4 subfiedls were 104.5/mm (54.3%), 51.0/mm (33.8%), 105.5/mm (85.6%), and 124.3/mm (93.5%) compared to the nonischemic control group, respectively. At day 4, the mean numbers of pyramidal neurons in CA1, CA2, CA3, and CA4 subfields were 3.2/mm (1.7%), 51.5/mm(34.2%), 95.3/mm (77.4%), and 112.5/mm (84.6%), respectively. At day 7, the mean numbers of pyramidal neurons in CA1, CA2, CA3, and CA4 subfiedls were 0.8/mm (0.4%), 5.7/mm(3.8%), 9.8/mm (8.0%), and 5.0/mm (3.7%), respectively. The mean numbers of apoptotic positive neurons in the CA1 subfield at day 2, 4, and 7 after reperfusion were 67.8/mm, 153.2/mm and 123.7/mm, respectively. These results suggest that the transient cerebral ischemia cause severe damages in most neurons at day 7 and that the prosminent apoptotic positive neurons in hippocampal pyramidal layer are the delayed neuronal death induced by ischemia.

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The Effects of Superior Cervical Sympathetic Ganglion Block on the Acute Phase Injury and Long Term Protection against Focal Cerebral Ischemia/Reperfusion Injury in Rats (백서의 국소 뇌허혈/재관류로 인한 신경손상에서 상경부 교감 신경절 블록의 급성기 및 장기 보호효과)

  • Jeon, Hae Young;Joung, Kyoung Woon;Choi, Jae Moon;Kim, Yoo Kyung;Shin, Jin Woo;Leem, Jeong Gill;Han, Sung Min
    • The Korean Journal of Pain
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    • v.21 no.2
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    • pp.119-125
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    • 2008
  • Background: Cerebral blood vessels are innervated by sympathetic nerves from the superior cervical ganglia (SCG), and these nerves may influence the cerebral blood flow. The purpose of the present study was to evaluate the neuroprotective effect of superior cervical sympathetic ganglion block in rats that were subjected to focal cerebral ischemia/reperfusion injury. Methods: Eighty male Sprague-Dawley rats (270-320 g) were randomly assigned to one of two groups (the ropivacaine group and a control group). In all the animals, brain injury was induced by middle cerebral artery (MCA) reperfusion that followed MCA occlusion for 2 hours. The animals of the ropivacaine group received $30{\mu}l$ of 0.75% ropivacaine, and their SCG. Neurologic score was assessed at 1, 3, 7 and 14 days after brain injury. Brain tissue samples were then collected. The infarct ratio was measured by 2.3.5-triphenyltetrazolium chloride staining. The terminal deoxynucleotidyl transferase mediated dUTP-biotin nick-end labeled (TUNEL) reactive cells and the cells showing caspase-3 activity were counted as markers of apoptosis at the caudoputamen and frontoparietal cortex. Results: The death rate, the neurologic score and the infarction ratio were significantly less in the ropivacaine group 24 hr after ischemia/reperfusion injury. The number of TUNEL positive cells in the ropivacaine group was significantly lower than those values of the control group in the frontoparietal cortex at 3 days after injury, but the caspase-3 activity was higher in the ropivacaine group than that in the control group at 1 day after injury. Conclusions: The study data indicated that a superior cervical sympathetic ganglion block may reduce the neuronal injury caused by focal cerebral ischemia/reperfusion, but it may not prevent the delayed damage.