脑淋巴引流阻滞对缺血大鼠脑组织谷氨酸、Ca~(2+)含量和NMDAR1表达的影响

目的:探讨脑梗塞后给予大鼠颈淋巴管阻塞对缺血侧大脑皮质脑含水量、Ca2+和谷氨酸含量、脑梗塞体积以及N-甲基-D-天冬氨酸受体1(NMDAR1)表达水平等的影响。方法:用线栓法复制大鼠大脑中动脉阻塞(MCAO)模型,以及行大鼠大脑中动脉阻塞15min后摘除双侧颌下腺的颈浅和颈深淋巴结,制成脑梗塞后颈淋巴管阻塞(MCAO+CLB)模型,检测缺血侧大脑皮质脑含水量、Ca2+和谷氨酸含量、脑梗塞体积以及NMDAR1mRNA表达水平和免疫活性的变化。结果:在不同的时间点,MCAO+CLB组大鼠上述各指标要比MCAO组明显升高(P0.05)。结论:颈淋巴管阻塞通过提高脑含水量、Ca2+和谷氨酸含量、脑梗塞体积以及上调NMDAR1表达水平而加重脑梗塞。     

Intravenously delivered neural stem cells migrate into ischemic brain,differentiate and improve functional recovery after transient ischemic stroke in adult rats

Stem cell transplantation may provide an alternative therapy to promote functional recovery after various neurological disorders including cerebral infarct. Due to the minimal immunogenicity and neuronal differentiation potential of neural stem cells (NSCs), we tested whether intravenous administration of mice-derived C17.2 NSCs could improve neurological function deficit and cerebral infarction volume after ischemic stroke in rats. Additionally, we evaluated the survival, migration, proliferation, and differentiation capacity of transplanted NSCs in the rat brain. Intravenous infusion of NSCs after middle cerebral artery occlusion (MCAO) showed better performance in neurobiological severity scores after MCAO compared to control. However, the volume of cerebral infarction was not different at 7 days after MCAO compared with control. Transplanted NSCs were detected in the ischemic region but not in the contralateral hemisphere. NSCs differentiated into neurons or astrocytes after MCAO. These data suggest that intravenously transplanted NSCs can migrate, proliferate, and differentiate into neurons and astrocytes in the rat brain with focal ischemia and improve functional recovery.     

二氢杨梅素下调大鼠缺血性脑卒中脑组织炎症小体Nod样受体蛋白3的表达

目的 研究二氢杨梅素(DHM)在大鼠缺血性脑卒中治疗方面的作用,并探讨其对炎症小体Nod样受体蛋白3(NLRP3)表达的影响.方法 取70只SD大鼠,利用线栓法构建大鼠大脑中动脉栓塞(MCAO)模型,采用Longa评分、TTC染色、Nissl染色、免疫组织化学染色及Western blotting等方法,探讨DHM对M...     

Anti‐Inflammatory and Neuroprotective Effects of Triptolide via the NF‐κB Signaling Pathway in a Rat MCAO Model

Stroke is the leading cause of neurological disability in humans. Middle cerebral artery occlusion (MCAO) followed by reperfusion is widely accepted to mimic stroke in basic medical research. Triptolide is one of the major active components of the traditional Chinese herb Tripterygium wilfordii Hook F, and has been reported to have potent anti‐inflammatory and immunosuppressive properties. Since its preclinical effects on stroke were still unclear, we decided to study the effects of Triptolide on focal cerebral ischemia/reperfusion injury in this study. The results showed that Triptolide treatment significantly attenuates brain infarction volume, water content, neurological deficits, and neuronal cell death rate, which were increased in the MCAO model rats. Immunohistochemistry was used to analyze the expression of glial fibrillary acidic protein (GFAP), Cyclooxygenase‐2 (COX‐2), inducible nitric oxide (iNOS), and NF‐κB in the ischemic brains. The administration of Triptolide showed down‐regulation of the iNOS, COX‐2, GFAP, and NF‐κB expression in MCAO rats. It also increased the expression of bcl‐2, and suppressed levels of bax and caspase‐3 compared with the MCAO group. Our findings revealed that Triptolide exerts its neuroprotective effects against inflammation with the involvement of inhibition of NF‐κB activation. Anat Rec, 299:256–266, 2016. © 2015 Wiley Periodicals, Inc.     

骨髓单个核细胞移植脑梗塞大鼠的行为学评价及对乙酰胆碱水平的影响

目的观察人骨髓单个核细胞（BMMC）移植对脑梗塞大鼠的影响。方法制备大鼠大脑中动脉闭塞（MCAO）模型,将骨髓单个核细胞静脉注射脑梗塞大鼠体内进行治疗。用平横木行走实验评价大鼠运动功能;用TTC染色法观察脑梗塞区坏死比例;采用化学显色反应法测定各组大鼠脑组织和血浆中乙酰胆碱（Ach）浓度和乙酰胆碱酯酶（TChE）活性。结果与模型组比较,给予骨髓单个核细胞组大鼠行为学评分明显变高（P〈0.05）,大脑坏死面积明显减少（P〈0.01）,脑组织和血浆中的Ach水平和TChE活性显著增高和增强（P〈0.05）。结论静脉注射骨髓单个核细胞可促进脑梗塞大鼠中枢神经系统功能恢复及胆碱能系统恢复。     

胡黄连苷Ⅱ对大鼠脑缺血再灌注损伤的干预作用

目的研究胡黄连苷Ⅱ对大鼠脑缺血再灌注损伤的神经保护作用。方法应用线栓法建立大鼠大脑中动脉闭塞再灌注(MCAO/R)模型,经尾静脉注射胡黄连苷Ⅱ(10mg/kg)和丹参素钠(10mg/kg)干预治疗,Bederson法评价动物的神经行为功能,氯化三苯基四氮唑(TTC)染色观察脑梗死体积,组织病理学观察神经细胞结构,原位缺口末端标记法(TUNEL)检测细胞凋亡。结果脑缺血再灌注损伤后,大鼠均表现神经行为功能障碍,缺血侧出现脑梗塞病灶,神经细胞凋亡数量均高于假手术组。胡黄连苷Ⅱ和丹参素钠治疗后,神经细胞凋亡数量明显减少、脑梗塞体积显著缩小,动物神经行为功能明显改善,与模型对照组比较均有显著性差异(P0.05)。胡黄连苷Ⅱ组脑梗塞体积显著小于丹参素钠组(P0.05)。结论胡黄连苷Ⅱ可能通过抑制细胞凋亡,缩小梗死体积而改善大鼠的神经行为功能。     

局灶性脑梗死模型大鼠相对体质量、Bederson评分与梗死类型的鉴别

背景：采用MCAO法制作大鼠脑缺血模型时,通过分析Bederson评分结果并不能完全可靠的诊断皮质下梗死。 目的：对SD大鼠皮质梗死和皮质下基底核区梗死在不同时间点的体质量与Bederson评分结果进行比较。 方法：参照Zea Longa的线栓造模方法制作大脑中动脉闭塞模型SD大鼠,栓塞100 min后拔出线栓。术后将大鼠进行磁共振成像扫描,根据有无梗死灶及梗死部位的不同将大鼠分为：皮质下基底核区梗死组(n=13)、皮质梗死组(n=25)、未出现梗死组(n=10)。对3组大鼠大脑中动脉闭塞后7周内的体质量与Bederson评分结果进行监测。 结果与结论:皮质下梗死组与无梗死组在各时间点大鼠相对体质量相比无显著性意义(P > 0.05)。皮质梗死组大鼠的相对体质量在大脑中动脉闭塞后2周内明显小于皮质下梗死组,在大脑中动脉闭塞后3周内明显小于无梗死组(P< 0.05)。皮质下梗死组大鼠造模后第1天Bederson评分结果与皮质梗死组相比差异无显著性意义,但都明显高于无梗死组(P < 0.05)。提示可结合大鼠大脑中动脉闭塞后第1天的相对体质量与Bederson评分结果对大鼠的梗死类型进行鉴别。     

针刺对MCAO大鼠血SOD、MDA、GSH-PX的影响

研究针刺对大脑中动脉阻断(MCAO)所致局限性脑缺血大鼠血液超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH—PX)的影响。采用穿线法阻断大脑中动脉复制大鼠脑缺血模型，研究针刺人中、内关以及曲池、足三里等穴位对大鼠血SOD、MDA、GSH—PX的影响，并与针刺地机、经渠穴位和假手术组对照。结果表明，针刺曲池、足三里组血液MDA含量降低；各针刺组血液中SOD、GSH—PX水平无明显改变。针刺曲池、足三里穴位可降低MDA的含量。     

Rodent brain imaging with SPECT/CT

We evaluated methods of imaging rat models of stroke in vivo using a single photon emission computed tomography (SPECT) system dedicated to small animal imaging (X-SPECT, Gamma Medica-Ideas, Northridge, CA). An animal model of ischemic stroke was developed for in vivo SPECT/CT imaging using the middle cerebral artery occlusion (MCAO) technique. The presence of cerebral ischemia was verified in ex vivo studies using triphenyltetrazolium chloride (TTC) staining. In vivo radionuclide imaging of cerebral blood flow was performed in rats following MCAO using dynamic planar imaging of 99mTc-exametazime with parallel hole collimation. This was followed immediately by in vivo radionuclide imaging of cerebral blood flow with 99mTc-exametazime in the same animals using 1-mm pinhole SPECT. Correlated computed tomography imaging was performed to localize radiopharmaceutical uptake. The animals were allowed to recover and ex vivo autoradiography was performed with separate administration of 99mTc-exametazime. Time activity curve of 99mTc-exametazime showed that the radiopharmaceutical uptake could be maintained for over 9 min. The activity would be expected to be relatively stable for a much longer period, although the data were only obtained for 9 min. TTC staining revealed sizable infarcts by visual observation of inexistence of TTC stain in infracted tissues of MCAO rat brains. In vivo SPECT imaging showed cerebral blood flow deficit in the MCAO model, and the in vivo imaging result was confirmed with ex vivo autoradiography. We have demonstrated a capability of imaging regions of cerebral blood flow deficit in MCAO rat brains in vivo using a pinhole SPECT dedicated to small animal imaging.     

五味子醇甲通过调控自噬流减轻大鼠脑缺血再灌注损伤

目的:探究五味子醇甲(Sch A)减轻大鼠脑缺血再灌注损伤的作用及其潜在机制.方法:成年雄性SD大鼠随机分为假手术组(sham组)、模型组[大脑中动脉闭塞(MCAO)组]及Sch A低、中、高剂量治疗组,每组6只.制备大鼠左侧MCAO模型,90 min后再灌注,治疗组Sch A的剂量分别为40、80和160μg·kg?...     

Electrophysiological transcortical diaschisis after middle cerebral artery occlusion (MCAO) in rats

Remote changes in brain function following stroke are called diaschisis. These remote effects may contribute to the neurological deficit following brain infarction; in addition they may lead to post-stroke epilepsy and affect functional recovery. In the present study we addressed the question of whether an increase in excitability can be observed contralateral to middle cerebral artery (MCA) infarction. Permanent occlusion of the middle cerebral artery (MCAO) was induced experimentally in rats with an intraluminal silicon-coated filament. Seven days later, brain excitability was tested with extracellulare recording techniques in neocortical coronal brain slices using a paired-pulse stimulus protocol. In rats with MCAO, excitability was increased in the neocortex contralateral to the infarction compared with the control group. These alterations extended through wide parts of the contralateral neocortex. The study demonstrates that MCAO causes transcallosal electrophysiological diaschisis. Together with results obtained previously with photothrombotic cortical lesions, it can be concluded that these remote effects are not due to characteristics of the individual lesion model, but are common consequences of brain lesions.     

Anti-oxidative effects of d-allose, a rare sugar, on ischemia-reperfusion damage following focal cerebral ischemia in rat

The present study investigates the anti-oxidative effects of D-allose on ischemic damage. Rats were subjected to transient middle cerebral artery occlusion (MCAO) for 1 h under pentobarbital anesthesia. D-allose was intravenously infused during occlusion and a further 1 h after reperfusion (400 mg/kg). The effects of D-allose on focal cerebral ischemia were examined by measuring brain damage (infarction and atrophy volume) and behavioral deficits 7 days after MCAO. In another set of rats, apurnic/apyrimidic abasic sites (AP-sites) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), oxidative stress markers, were investigated 24 h after MCAO to examine the anti-oxidative effects of D-allose. Brain damage and behavioral deficits were significantly decreased by D-allose administration compared to vehicle. The number of AP-sites and 8-OHdG levels were also reduced by D-allose. Thus, the present study suggests that D-allose has anti-oxidative effects and induces neuroprotection in focal cerebral ischemia.     

脑淋巴引流障碍加重大脑中动脉阻塞大鼠缺血性脑水肿

目的：探讨脑淋巴引流阻滞对脑缺血性的影响。方法：将76只Wistar大鼠随机分为大脑中动脉阻塞(MCAO)组和。MCAO加脑淋巴引流阻断组(MCAO CLO)组，在术后24、48、72h分别检测缺血区脑组织水、电解质含量。结果在手术后各时间点，MCAO大鼠缺血区脑组织的含水率、Na^ 含量、Ca^2 含量均显著增加，而K^ 显著下降。MCAO CLO组大鼠的上述指标变化更为显著。结论：脑淋巴引流障碍能明显加重MCAO后缺血性脑水肿。     

A comparison of the early development of ischemic brain damage in normoglycemic and hyperglycemic rats using magnetic resonance imaging

The early evolution of ischemic brain injury under normoglycemic and streptozotocin-induced hyperglycemic plasma conditions was studied using magnetic resonance imaging (MRI). Male Sprague-Dawley rats were subjected to either permanent middle cerebral artery occlusion (MCAO), or 1-h MCAO followed by reperfusion using the intraluminal suture insertion method. The animals were divided into four groups each with eight rats: normoglycemia with permanent MCAO, normoglycemia with 1-h MCAO, hyperglycemia with permanent MCAO, and hyperglycemia with 1-h MCAO. Diffusion-weighted images (DWIs) and T2-weighted images (T2WIs) were aquired every l h from 20 min until 6 h after MCAO, at which time cerebral plasma volume images (PVIs) were acquired. Tissue infarction was determined by triphenyltetrazolium chloride staining at 7 h after MCAO. The ischemic damage, measured as the area of DWI and T2WI hyperintensity and tissue infarction, increased significantly in hyperglycemic rats in both permanent and transient MCAO models. In the permanent MCAO model, the maximal apparent water diffusion coefficient (ADC) decline under either normoor hyperglycemia was about 40%, but the speed of ADC drop was faster in hyperlgycemic rats than in normoglycemic rats. Reperfusion after l h of MCAO in normoglycemic rats partly reversed the decline in ADC, whereas the low ADC area continued to expand after reperfusion in the hyperlgycemic group. Between the two hyperglycemic groups with either permanent MCAO or reperfusion, no significant difference was found in the infarct volume measured at 7 h after MCAO. However, reperfusion dramatically increased the extent and accelerated the development rate of vasogenic edema. ADC in the hyperglycemic reperfusion group also dropped to a lower level. A large no-reflow zone was found in the ischemic hemisphere in the hyperglycemic reperfusion group. This study provides strong evidence to support that preischemic hyperglycemia exacerbates ischemic damage in both transient and permanent MCAO models and demonstrates, using MRI, that reperfusion under preischemic hyperglycemia accelerates the evolution of early ischemic injury.     

白介素10对大鼠缺血梗死灶周围脑组织Bcl-2和Bax表达的作用研究

目的 探讨白介素10对大鼠脑缺血梗死灶周围Bcl-2和Bax表达的作用.方法 18只SD大鼠随机分为假手术组(Sham组)、脑缺血组(MCAO组)、脑缺血 溶剂对照组(Vehicle组)和脑缺血 IL-10干预组(IL-10组),免疫组化和RT-PCR法观察术后24h梗死灶周围脑组织Bcl-2和Bax表达水平的变化.结果与Sham相比,MCAO组梗死灶周围脑组织Bcl-2和Bax的表达显著上调,Bcl-2/Bax比值显著下降;与Vehicle组比,IL-10组Bcl-2的表达显著上调,Bax表达显著下调,Bcl-2/Bax比值显著增加.结论 IL-10与脑缺血梗死灶周围Bcl-2表达上调,Bax表达下调,Bcl-2/Bax比值增加有关,提示IL-10可能与抑制梗死灶周围脑组织神经细胞凋亡有关.     

LSCI检测不同缺血期对大鼠缺血再灌注过程脑血流的影响

目的　考察不同缺血期对大鼠缺血再灌注过程脑血流的影响。 方法　通过激光散斑成像技术（LSCI）检测大鼠大脑中动脉不同栓塞时间后,对再灌注过程中脑血流的影响,并对再灌注过程中的低灌注状态、无复流现象、血流流速及管径变化进行研究分析。 结果　2 h的栓塞后,大鼠脑部血流量趋向低灌注状态,约为栓塞前血流基值的(35±10)%;栓塞时间越长,无复流现象越多;在再灌注期间,缺血2 h组的血流比0.5 h组的低灌注水平低10%。 结论　长时间的脑缺血期再灌注过程可能是造成脑损伤程度加重的主要原因之一。LSCI可应用于脑部血流实时监测,操作简便,成像灵敏、稳定,结果可靠。     

构建大脑中动脉阻塞脑缺血模型大鼠的类型分析

背景：线栓法造成短暂性大脑中动脉阻塞是研究大鼠局灶性脑缺血普遍使用的模型制作方法。但制作大鼠脑缺血模型的类型存在一定差异,可能导致实验结果的偏差。 目的：分析大脑中动脉阻塞线栓法制作大鼠脑缺血模型的类型及其影响因素。 方法：雄性SD大鼠166只,参照Longa线栓法造模,术后24 h行MRI扫描,根据扫描结果将大鼠分成皮质梗死组、皮质下梗死组及无梗死组,分析造模时线栓插入的深度。 结果与结论：皮质梗死组、皮质下梗死组和无梗死组大鼠的线栓插入深度分别为(19.9±0.9),(19.0±1.1)和(17.7±1.3) mm,皮质梗死组大鼠的线栓插入最深,而无梗死组的线栓插入最浅(P < 0.01)。提示插入深度不同导致的大鼠脑梗死的类型也不同,线栓插入越深,皮质梗死的概率可能越大。     

跑步运动对脑卒中大鼠的海马可塑性的保护作用

目的 探索跑步运动对脑卒中大鼠的海马可塑性的保护作用及其生物学机制。 方法 成年雄性 大鼠大脑中动脉闭塞 (middle cerebral artery occlusion, MCAO) 90 min, 24 h 后随机分为运动组和非运动 组。 两周后, 对大鼠的神经功能缺损情况进行评分; 水迷宫法检测大鼠的学习和记忆功能; 2, 3, 5 三苯 四氮唑氯化物染色和 HE 染色评估大鼠大脑梗塞水平和组织学损伤; NeuN 染色观察神经元损伤水平; 蛋白 质免疫印迹法检测 COX-2、 IL-1β 和 TNF-α 的蛋白表达水平。 结果 MCAO 后, 运动组的神经功能缺损、 学习和记忆功能、 脑梗死体积指标均优于非运动组。 与这些结果一致, 运动组的大鼠脑组织中的神经元损 伤数目也显著减少, 脑内炎性反应得到了抑制。 结论 运动可以改善 MCAO 后神经功能评分、 减少梗死体 积, 其潜在机制与炎性反应的抑制对神经元的保护有关。     

早期运动训练对脑梗死后缺血半暗带GAP-43、Nogo-A及GFAP表达的影响*

目的： 探讨早期运动训练对脑梗死缺血半暗带区轴突生长相关蛋白43 （ GAP-43）、神经突起生长抑制因 子A（ Nogo-A）和神经胶质纤维酸性蛋白（ GFAP）表达的调控作用,及其对大鼠神经功能恢复的影响。方法 ： 健康成年雄性Wistar 大鼠,按随机数字表法分为假手术组、模型组、训练组。采用线栓法建立大脑中动脉闭塞 （ MCAO）大鼠模型,术后24 h 进行强度渐增的跑台运动训练14 d 和28 d。采用改良神经功能缺损评分（ mNSS） 评估神经功能;平衡木行走试验评估大鼠神经行为学改变;H-E 染色观察各组缺血半暗带区神经元病理形态学变 化;免疫印迹检测大鼠脑缺血半暗带GAP-43、Nogo-A 和GFAP蛋白表达变化;结果： 与假手术组相比,模型组 大鼠mNSS评分和平衡木试验评分均显著升高,脑缺血半暗带区GAP-43 和GFAP蛋白表达上调,而Nogo-A 的表 达下调。与模型组比较,跑台训练组大鼠mNSS评分与平衡木试验评分均显著降低,脑缺血半暗带区GAP-43 表 达上调,而Nogo-A 和GFAP表达下调。结论： 早期跑台训练可以促进轴突再生,抑制胶质瘢痕形成,最终改善 脑梗死大鼠神经功能障碍。