Effects of Hypothermia on Subventricular Neural Stem Cells Following Focal Cerebral Ischemia in Adult Rats

低温对成年大鼠局灶性脑缺血后室下神经干细胞的影响

• 批准号: 15591641
• 负责人: YANO Toshiyuki
• 金额: $ 2.24万
• 依托单位: Kumamoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15591641/
• 关键词: hypothermia; neural stem cells; subventricular zone; focal cerebral ischemia; immunohistochemistry; DiI; rat; ependymal cell; cerebral ischemia; stem cell

Background : Recently, neural stem cells have been identified in the subventricular zone(SVZ) and the hippocampal dentate gyrus of adult rodents. Hypothermia is well known to provide neuroprotection following various brain insults, In this study, we examined if hypothermia activated neural stem cell of the SVZ exposed to focal cerebral ischemia.Materials and Methods : Adult male Wistar rats were anesthetized, intubated and ventilated with isoflurane and N_2O/O_2. DiI(0.2%,10 μL) was injected into the left lateral ventricle. After preparation the animals were assigned to the following groups : group 1(hypothermia 32.5±0.5℃), group 2(ischemia/hypothermia 32.5±0.5℃), and group 3(ischemia/normothermia 37.5±0.5℃. Ischemia(120 min) was induced by right middle cerebral occlusion with a 4-0 nylon suture and confirmed by the decreased regional cerebral blood flow using laser Doppler flowmetry. Hypothermia for 6 hours was applied immediately after the initiation of ischemia. Seven days after hyp … More othermia or ischemia, bromodeoxyuridine(BrdU) was administered intraperitoneally 10 and 2 hours before sacrifice and the brains were removed, fixed with 4% paraformadlehyde in PBS, cryoprotected with graded sucrose solutions, frozen and cut for DiI fluolescence detection and fluolescent immunohistochemistry. Separately, the brains were stained with triphenyltetrazolium chloride for assessment of infarct area.Results : In the group 3,DiI-positive cells migrated from the SVZ toward the striatum on days 7 and 14. Infarct area on day 7 was much larger in the group 3 than in the group 2. Hypothermia did not facilitate the migration of DiI positive cells from the SVZ. BrdU and doublecortin were expressed in the SVZ and the rostral migratory stream in all groups and into the infarct region in the groups 2 and 3. Nestih that is expressed in neural precursors was developed in the whole ischemic hemisphere but not in the contralateral hemisphere. Migrating DiI-positive cells occasionally expressed NeuN or GFAP. Howerver, hypothermia did not influence the expression of BrdU, doublecortin, nestin, NeuN, and GFAP.Conclusion : Hypothermia did not activate the subventricular neural stem cells to prolirerate, migrate, and difierentiate into neurons or glia in the injured striatum following focal cerebral ischemia. Less

背景：最近，在成年啮齿动物的脑室下区（SVZ）和海马齿状回已鉴定出神经干细胞。众所周知，在各种大脑感染后提供神经保护性，在这项研究中，我们检查了暴露于暴露于局灶性脑缺血的SVZ的神经溶质细胞。材料和方法：成年雄性Wistar大鼠在肠内插入，插管，插管，插管，并用isoflurane and isoflurane and n _2o和n_2O.22。将DII（0.2％，10μL）注入左侧通气中。制备后，将动物分配到以下组：第1组（低温32.5±0.5℃），第2组（缺血/低温32.5±0.5℃）和第3组（缺血/Normchemia/Normothermia 37.5±0.5℃）。缺血（120分钟）是由右脑中闭塞诱导的，并用4-0尼龙缝合线诱导，并通过使用激光多普勒流动仪进行改善的区​​域脑血流证实。局部缺血后立即应用低温6小时。催眠后的7天……更多的其他贫血或缺血，溴脱氧尿苷（BRDU）被腹膜内进行10和2小时，然后在牺牲前2小时，并去除大脑，并用PBS中的4％的甲甲基固定在PBS中，用冷冻溶液和diiiii氟含糖的液体溶液和含量的免疫原子固定在PBS中，并固定。另外，将大脑用三苯基四唑量染色，以评估梗塞区域。回归：在第3组中，DII阳性细胞在第7和14天从SVZ迁移到纹状体。第7天的梗塞区域在第3组中的第3组中的第3组大得多。 BRDU和DoubleCortin在所有组中的SVZ中表达，并在第2组和第3组中的延髓迁移，进入了在神经前体中表达的NestiH，在整个缺血性半球中开发出来，但在对侧半球中却没有。迁移的DII阳性细胞偶尔表达Neun或GFAP。 Howerver，低温不影响BRDU，Doublecortin，Nestin，Neun和GFAP的表达。结论：低温没有激活脑室下神经元干细胞在局灶性灌注斑点斑点局部的受伤性纹状体中促进，迁移并分裂为神经元或神经元。较少的