稳定的大鼠大脑中动脉栓塞脑梗死模型的建立

目的探讨使用激光多普勒血流监测技术制作稳定的大鼠大脑中动脉栓塞脑梗死模型(middle cerebral artery occlusion,MCAO)的可行性。方法 16只SD雄性大鼠随机分成2组:实验组和对照组各8只。实验组将模型制作过程中脑血流下降至基础值的30%判定为模型制作成功;对照组不监测脑血流,将尼龙栓线插入深度为1.8 cm判定为模型制作成功。模型前和模型后24 h分别行神经损伤严重程度评分(modified neurological severity scores,m NSS);模型后24 h处死大鼠取脑,行2,3,5-三苯氯化四氮唑(TTC)染色并计算脑梗死体积。结果实验组8只大鼠模型后24 h均出现典型偏瘫症状,m NSS评分稳定在10分~13分,梗死体积稳定性和均一性好,为(37.5±3.9)%。对照组8只大鼠m NSS评分稳定性较差,其中5只大鼠的m NSS评分为10分~13分,5只大鼠的脑梗死灶和实验组相似,但有3只大鼠的脑梗死体积明显小于实验组(P0.05)。实验组的模型成功率为100%,对照组的模型成功率为62.5%(P0.05)。结论激光多普勒血流监测技术可以显著提高大鼠MCAO模型的成功率、稳定性和均一性。     

缺血预适应对小鼠脑缺血再灌注损伤模型血脑屏障的保护作用及机制

目的:通过研究缺血预适应对小鼠脑缺血再灌注损伤血脑屏障通透性的影响,探讨缺血预适应的脑保护作用及相关分子机制。方法:取清洁健康成年小鼠72只,随机分为脑缺血预适应组(brain ischemic precondition,BIP),脑缺血再灌注组(middle cerebral artery occlusion and reperfusion,MCAO/R)和假手术组(sham group),每组均24只,采用zealonga线栓法栓塞小鼠大脑中动脉建立BIP模型和MCAO/R模型,通过氯化三苯基四氮唑(triphenyl tetrazolium chloride,TTC)染色计算脑梗死面积,改良神经功能缺损评分(modified neurological severity scores,m NSS)对脑缺血再灌注神经损伤程度进行评估,测干-湿重法以及伊文氏蓝(Evans blue,EB)示踪结合脑组织EB定量法评价血脑屏障(blood brain barrier,BBB)的损伤程度,采用免疫组化法检测各组脑组织低氧诱导因子-1α(HIF-1α)和血管内皮生长因子(VEGF)的表达。结果:与MCAO组相比,BIP组显著降低缺血再灌注后m NSS评分,缩小了梗死面积并减轻脑水肿,有效的保护BBB功能,BIP组再灌注24 h时脑梗死灶周围皮质区HIF-1α及VEGF的表达均明显上调,差异有统计学意义(P0.05)。结论:BIP对小鼠脑缺血再灌注损伤模型BBB有一定的保护作用,其机制可能与其诱导HIF-1α及VEGF的表达上调有关。     

Homer1a基因敲除对小鼠局灶性脑缺血再灌注损伤的作用

目的:通过研究homer1a基因敲除小鼠脑缺血再灌注损伤及海马区星形胶质细胞活化、数目形态变化,探讨homer1a基因在脑缺血损伤中的作用及机制。方法:取雄性homer1a基因敲除(Knock Out,KO)小鼠及同窝野生型(Wild Type,WT)小鼠各15只,分为基因敲除假手术组(Sham Knock Out,SKO,n=3)、基因敲除型缺血2 h再灌注24 h组(Model Knock Out,MKO,n=12)、野生型假手术组(Sham Wild Type,SWT,n=3)及野生型缺血2 h再灌24h组(Model Wild Type,MWT,n=12)。线栓法闭塞小鼠大脑中动脉制作脑缺血再灌注损伤模型(middle cerebral artery occlusion and reperfusion,MCAO/R),在缺血再灌注损伤前(0 h)及缺血再灌注后3 h、6 h、12 h、24 h后进行改良版神经损伤严重性评分(modified Neurological severity scores,m NSS)、2,3,5—氯化三苯基四氮唑(2,3,5triphenyltetrazolium chloride,TTC)染色、苏木素—伊红染色(Hematoxylin-eosin staining,HE)、原位末端转移酶标记技术(terminal deoxynucleotidyl transferase(Td T)-mediated deoxyuridine triphosphate(d UTP)nick end labeling,TUNEL)检测及免疫荧光染色观察海马区星形胶质细胞神经纤维酸性蛋白(Glial Fibrillary Acidic Protein,GFAP)改变。结果:SKO组、SWT组行为学m NSS评分均为0分,TTC染色未见梗死灶。TUNLE及GFAP染色阳性细胞数很少且未见统计学差异(P0.05)。脑缺血再灌注24 h后,MKO组m NSS评分较MWT组高;TTC染色MKO组较MWT组梗死百分比高;MKO组较MWT组TUNEL凋亡率高;GFAP免疫荧光染色阳性数MKO组少于MWT组,且均有统计学差异(P0.05)。结论:homer1a基因敲除加重了小鼠脑缺血再灌注损伤,星形胶质细胞可能参与并发挥复杂作用。     

线栓法制备不同体重KM小鼠局灶性脑缺血/再灌注模型的建立及评价

目的线栓法制备小鼠脑缺血/再灌注模型,并探讨影响该模型稳定性的因素。方法 KM小鼠100只,雌雄各半,体重20～39 g,分别将雌雄KM小鼠随机分为假手术组(n=20)和不同体重实验组(n=80)。其中实验组按小鼠体重分为以下8组:A组(♂,20～24 g)、B组(♂,25～29 g)、C组(♂,30～34 g)、D组(♂,35～39g),E组(♀,20～24 g)、F组(♀,25～29 g)、G组(♀,30～34 g)、H组(♀,35～39 g),每组10只。线栓栓塞法制备局灶性脑缺血/再灌注模型,选用单丝尼龙线(直径0.128～0.180 mm),液体石蜡处理浸泡后,从右侧颈总动脉进线,阻塞大脑中动脉血流,再灌注时拔出线栓,并对模型进行评价,采用的主要观察指标是神经功能损伤评分和2,3,5-三苯基氯化四氮唑(TTC)染色。结果同假手术相比,不同体重实验组小鼠脑缺血再灌注后,出现神经行为功能异常,TTC染色脑组织显示出明显的梗塞灶。与C、D组相比,A、B两组行为学评分以及梗死灶体积显著性增加(P<0.01);与G、H组相比,E、F两组的行为学评分以及梗死灶体积也显著性增加(P<0.01,P<0.05)。雄性KM小鼠与雌性相比,成模率较高且死亡率相对较低。此外,A组与E组相比,其行为学评分显著增加(P<0.01);B组与F组相比,小鼠行为学评分以及脑梗塞体积显著增加(P<0.01)。结论体重在25 g左右的雄性KM小鼠制备模型成功率较高,死亡率较低,适合建立小鼠局灶性脑缺血/再灌注模型。     

15-HETE参与的脑缺血再灌注损伤中p-ERK1/2表达变化的研究

目的:通过应用15-脂氧化酶(15-Lipoxygenase,15-LOX)抑制剂去甲二氢愈创木酸(nordihydroguaiaretic acid,NDGA)抑制15-羟基-二十碳四烯酸(15-hydroxyeicosatetraenoic acid,15-HETE)的生成,观察缺血再灌注损伤中大鼠脑组织磷酸化细胞外信号调节酶(phosphor-extracellular signal-regulated kinase,p-ERK1/2)表达的变化,探讨p-ERK1/2在15-HETE参与的脑缺血再灌注损伤中的作用及其表达变化。方法:应用大脑中动脉线栓栓塞法(MCAO)制作大鼠脑梗死2小时再灌注模型。将大鼠随机分为三组:假手术组(sham组)、DMSO对照组、NDGA处理组。后两组再根据不同的灌注时间分为三个亚组:再灌注1小时组、再灌注6小时组、再灌注24小时组。采用TTC染色法检测再灌注24小时大鼠脑梗死体积;免疫印迹(Western blot)法测定梗死后再灌注不同时间点梗死核心区和梗死周围区的p-ERK1/2的表达。结果:假手术组仅有少量p-ERK1/2的表达。DMSO对照组梗死核心区p-ERK1/2的表达从梗死再灌注后1小时即开始逐渐升高(1.43±0.06),6小时达高峰(2.02±0.14),24小时有所下降(1.16±0.21),与假手术组(0.62±0.08)比较P值均0.01;梗死周围区p-ERK1/2表现出相同的变化趋势。与DMSO对照组比较,NDGA处理组大鼠脑梗死体积显著减小(20.10±0.12%vs 17.24±0.16%,P=0.009,P0.05),各时间点p-ERK1/2的表达均下降。与梗死核心区相比较,梗死周围区24小时仍可检测到较高含量的p-ERK1/2(1.16±0.21 vs 1.86±0.14),但梗死核心区表达相对较少。结论:脑缺血再灌注损伤中,p-ERK1/2的表达增加,说明p-ERK1/2参与其中;应用NDGA后,p-ERK1/2的表达降低,脑梗死体积减小,证实p-ERK1/2参与了15-HETE介导的脑缺血再灌注损伤,并在此过程中可能参与了细胞的凋亡。     

UCF-101对大鼠局灶性脑缺血再灌注后JNK和ERK活性的影响

目的:探讨UCF-101对局灶性脑缺血再灌注大鼠脑内c-Jun氨基末端激酶(JNK)和胞外信号调节酶(ERK)活性的影响,进一步探讨UCF-101对局灶性脑缺血再灌注损伤脑保护作用的机制。方法:采用大脑中动脉线栓法(MCAO)建立大鼠局灶性脑缺血再灌注模型,随机分为假手术组,缺血再灌注组,UCF组,应用TTC检测大鼠脑梗死体积,TUNEL法检测神经元凋亡,Western blot检测ERK和JNK的活性。结果:UCF-101可下调脑缺血再灌注大鼠脑组织JNK蛋白的活性,上调ERK蛋白的活性,并降低梗死体积、坏死和凋亡细胞数。结论:UCF-101对大鼠局灶性脑缺血再灌注损伤有保护作用,抑制JNK凋亡通路、促进ERK生存通路,从而减轻细胞凋亡是其脑保护机制之一。     

亚低温联合镁剂对脑缺血再灌注大鼠保护作用的研究

目的:rt-PA溶栓为缺血性卒中最有效的治疗方法,脑血流再通后挽救濒临死亡的神经细胞同时,也可能发生更为严重而持久的脑缺血再灌注损伤。本研究探讨联合应用局部亚低温(32-35℃)及硫酸镁对局灶性脑缺血再灌注大鼠的保护作用及其可能机制。方法:通过线栓法建立大鼠大脑中动脉阻塞(MCAO)及再通模型,将50只雄性Wistar大鼠随机分为假手术组、常温组、亚低温组、硫酸镁组、亚低温+硫酸镁组,每组10例,采用Longa神经功能评分、TTC染色、干湿重法、TUNEL技术,检测和比较各组脑缺血再灌注后大鼠的神经功能、脑梗死体积、脑组织含水量及凋亡细胞数。结果:与常温组相比,亚低温组与亚低温+硫酸镁组的梗死体积、神经功能评分、脑组织含水量、凋亡细胞数均明显降低,差异有显著意义(P0.05);而与亚低温组相比,亚低温+硫酸镁组局灶脑缺血大鼠的脑梗死体积、神经功能评分、脑组织含水量、凋亡细胞数均显著减少,差异有显著意义(P0.05)。结论:与单独应用亚低温相比,局部亚低温与硫酸镁联合应用,对局灶性脑缺血再灌注大鼠可发挥更有效的脑保护作用。其机制可能与抑制脑缺血再灌注后凋亡及减轻脑水肿有关。二者联用可能为缺血性卒中患者提供一种减轻溶栓后再灌注损伤的有效脑保护方法。     

抑郁症患者经颅多普勒检测的对照分析

目的:分析并探讨抑郁症患者经颅多普勒(TCD)检测指标,为临床治疗提供借鉴.方法:选取我院2011年10月-2012年10月收治抑郁症患者120例,设为观察组,以同期健康正常人120例设为对照组,均行经颅多普勒检测,比较两组双侧大脑中动脉(MCA)、大脑前动脉(ACA)、大脑后动脉(PCA)、椎-基底动脉(VA-BA)等血流速度及搏动指数(pI)、阻力指数(RI).结果:观察组患者双侧大脑中动脉(MCA)、大脑前动脉(ACA)及大脑后动脉(P口CA)血流速度均明显高于对照组,而椎、基底动脉(VA-BA)血流速度明显低于对照组,组间比较差异显著(P＜0.05);对照组和观察组患者双侧大脑中动脉(MCA)、大脑前动脉(ACA)、大脑后动脉(PCA)、椎-基底动脉(VA-BA)搏动指数(PI)、阻力指数(RI)均处于正常范围内(0.6-1.0);另外,根据HAMD量表观察组抑郁程度,随着抑郁程度增强,双侧大脑中动脉(MCA)、前动脉(ACA)及后动脉(PCA)的血流速度逐渐增大,上述各值差异具有统计学意义(P＜0.05).结论:经颅多普勒检测出抑郁症患者的脑血流较正常人脑血流显著加快,且与抑郁的严重程度相关联,经颅多普勒监测抑郁症患者的脑血流变化,可以作为抑郁症患者的常规检查,为临床的治疗及诊断提供线索.     

小鼠脑缺血再灌注模型的构建及条件优化

目的:构建小鼠的脑缺血再灌注模型,并对其进行优化。方法:通过对线栓法缺血再灌注脑损伤模型的各个因素的对比实验,在线拴位置、线径、进线深度、小鼠种类等方面对该方法进行了优化改进。结果:造模后的脑片经TTC染色,梗死区域清晰;神经功能评分的体征明显。现有条件下构建的小鼠MCAO模型,成功率可以达到80%以上,成活率可以达到90%以上。与对照组相比,小鼠MCAO模型组血清SOD活性及MDA水平有显著变化(P0.01)。结论:经改进和优化,小鼠脑缺血再灌注模型的成功率和成活率大大提高且症状明显,对缺血缺氧性神经损伤研究具有一定的参考价值。     

促红细胞生成素对大鼠局灶性脑缺血再灌注神经元的保护作用及P53蛋白的表达

目的:探讨促红细胞生成素(Epo)对大鼠局灶性脑缺血再灌注神经细胞的保护作用.方法:60只SD大鼠随机分为缺血再灌注Epo治疗组(又分为高剂量A组、低剂量B组)、缺血再灌注组(C组)及假手术组(D组),采用大脑中动脉线栓法制备大鼠局灶性脑缺血再灌注模型.参考Longa的5分制法在大鼠麻醉清醒后进行评分,TTC染色法观察线栓侧的梗死体积,并检测脑组织含水量的变化,HE染色法观察脑缺血再灌注后脑组织的病理变化,TUNEL法观察神经细胞凋亡情况,western blot法观察p53蛋白的表达变化.结果:对照组比较,大鼠脑缺血再灌注后出现不同程度的脑梗死,24h后缺血中心区及周围区均可见到p53蛋白表达.缺血再灌注6h内给予Epo可显著改善大鼠神经功能评分,减少梗死体积及脑组织含水量,减轻病理学变化及神经细胞凋亡.结论:Epo通过调控神经细胞凋亡、改善缺血再灌注损伤而发挥脑保护作用,P53蛋白参与缺血再灌注后神经细胞凋亡机制.     

红茶菌在脑缺血再灌注损伤大鼠模型中的作用研究

摘要 目的：探讨红茶菌在脑缺血再灌注损伤大鼠模型中是否有改善效果。方法：将48只清洁级SD大鼠根据随机数字表法分为假手术组、模型组、红茶菌组、依达拉奉组。红茶菌组术前给予红茶菌液灌胃7天以及再灌注麻醉清醒后追加灌胃1次,依达拉奉组大鼠在再灌注前15 min经腹腔注射依达拉奉,模型组和假手术组给予生理盐水。遵循Zea Longa线栓法阻断大鼠大脑中动脉血流2 h后恢复再灌注24 h 建立MCAO模型,假手术组大鼠仅分离劲总动脉。再灌注24 h后,神经行为学评分评估脑损伤程度;TTC染色观察红茶菌对大鼠脑梗死面积比的影响并用Image J软件测定梗死面积;HE染色后观察大鼠脑组织皮层神经元病理形态学;透射电镜观察大鼠皮层神经元超微结构及线粒体形态。结果：脑缺血再灌注24 h后,对大鼠进行神经行为学评分,红茶菌组神经神经行为学评分为（2.21±0.60）,依达拉奉组神经行为学评分为（2.01±0.66）,均显著低于模型组（2.52±0.52）（P＜0.05）;TTC染色后观察到模型组大鼠大脑梗死灶明显,红茶菌组与依达拉奉组较模型组大鼠梗死面积明显减小;HE结果显示模型组大脑皮层神经元损伤明显,红茶菌组与依达拉奉组较模型组大脑皮层神经元坏死减轻,梗死面积缩小;透射电镜下观察到模型组大鼠染色质溶解,线粒体肿胀,红茶菌组与依达拉奉组较模型组溶解减少,线粒体结构较完整。结论：红茶菌可减轻脑缺血再灌注损伤大鼠模型的神经元损伤,有望成为改善脑缺血再灌注损伤的疗法或辅助疗法。     

Mouse Model of Intraluminal MCAO: Cerebral Infarct Evaluation by Cresyl Violet Staining

Stroke is the third cause of mortality and the leading cause of disability in the World. Ischemic stroke accounts for approximately 80% of all strokes. However, the thrombolytic tissue plasminogen activator (tPA) is the only treatment of acute ischemic stroke that exists. This led researchers to develop several ischemic stroke models in a variety of species. Two major types of rodent models have been developed: models of global cerebral ischemia or focal cerebral ischemia. To mimic ischemic stroke in patients, in whom approximately 80% thrombotic or embolic strokes occur in the territory of the middle cerebral artery (MCA), the intraluminal middle cerebral artery occlusion (MCAO) model is quite relevant for stroke studies. This model was first developed in rats by Koizumi et al. in 1986 ¹. Because of the ease of genetic manipulation in mice, these models have also been developed in this species ^2-3.Herein, we present the transient MCA occlusion procedure in C57/Bl6 mice. Previous studies have reported that physical properties of the occluder such as tip diameter, length, shape, and flexibility are critical for the reproducibility of the infarct volume ⁴. Herein, a commercial silicon coated monofilaments (Doccol Corporation) have been used. Another great advantage is that this monofilament reduces the risk to induce subarachnoid hemorrhages. Using the Zeiss stereo-microscope Stemi 2000, the silicon coated monofilament was introduced into the internal carotid artery (ICA) via a cut in the external carotid artery (ECA) until the monofilament occludes the base of the MCA. Blood flow was restored 1 hour later by removal of the monofilament to mimic the restoration of blood flow after lysis of a thromboembolic clot in humans. The extent of cerebral infarct may be evaluated first by a neurologic score and by the measurement of the infarct volume. Ischemic mice were thus analyzed for their neurologic score at different post-reperfusion times. To evaluate the infarct volume, staining with 2,3,5-triphenyltetrazolium chloride (TTC) was usually performed. Herein, we used cresyl violet staining since it offers the opportunity to test many critical markers by immunohistochemistry. In this video, we report the MCAO procedure; neurological scores and the evaluation of the infarct volume by cresyl violet staining.     

Characterization of a new double-filament model of focal cerebral ischemia in heme oxygenase-2-deficient mice

Variations in vascular anatomy in knockout mouse strains can influence infarct volume after middle cerebral artery (MCA) occlusion (MCAO). In wild-type (WT) and heme oxygenase-2 gene-deleted (HO2-/-) mice, infarcts were not reproducibly achieved with the standard intraluminal filament technique. The present study characterizes a double-filament model of MCAO, which was developed to produce consistent infarcts in both WT and HO2-/- mice. Diameters of most cerebral arteries were similar in WT and HO2-/- mice, although the posterior communicating artery size was variable. In halothane-anesthetized mice, two 6-0 monofilaments with blunted tips were inserted into the left internal carotid artery 6.0 and 4.5 mm past the pterygopalatine artery junction to reside distal and proximal to the origin of the MCA. The tissue "volume at risk" determined by brief dye perfusion in WT (59 +/- 2% of hemisphere; +/-SE) was similar to HO2-/- (62 +/- 4%). The volume of tissue with cerebral blood flow <50 ml.min(-1).100 g(-1) was similar in WT (35 +/- 9%) and HO2-/- (36 +/- 11%) during MCAO and at 3 h of reperfusion (<2%). After 1 h MCAO, infarct volume was greater in HO2-/- (44 +/- 6%) than WT (25 +/- 3%). After increasing MCAO duration to 2 h, the difference between HO2-/- (47 +/- 4%) and WT (36 +/- 3%) diminished, but infarct volume remained substantially less than the volume at risk. Infusion of tin protoporphyrin IX, an HO inhibitor, during reperfusion after 1 h MCAO increased infarct volume in WT but not significantly in HO2-/- mice, although infarct volume remained less than the volume at risk. Thus greater infarct volume in HO2-/- mice is not attributable to a greater volume at risk, lower intraischemic blood flow, or poor reflow, but rather to a neuroprotective effect of HO2 activity. The double-filament model may be of use as an alternative in other murine knockout strains in which the standard filament model does not yield consistent infarcts.     

Embolic Middle Cerebral Artery Occlusion (MCAO) for Ischemic Stroke with Homologous Blood Clots in Rats

Clinically, thrombolytic therapy with use of recombinant tissue plasminogen activator (tPA) remains the most effective treatment for acute ischemic stroke. However, the use of tPA is limited by its narrow therapeutic window and by increased risk of hemorrhagic transformation. There is an urgent need to develop suitable stroke models to study new thrombolytic agents and strategies for treatment of ischemic stroke. At present, two major types of ischemic stroke models have been developed in rats and mice: intraluminal suture MCAO and embolic MCAO. Although MCAO models via the intraluminal suture technique have been widely used in mechanism-driven stroke research, these suture models do not mimic the clinical situation and are not suitable for thrombolytic studies. Among these models, the embolic MCAO model closely mimics human ischemic stroke and is suitable for preclinical investigation of thrombolytic therapy. This embolic model was first developed in rats by Overgaard et al.¹ in 1992 and further characterized by Zhang et al. in 1997². Although embolic MCAO has gained increasing attention, there are technical problems faced by many laboratories. To meet increasing needs for thrombolytic research, we present a highly reproducible model of embolic MCAO in the rat, which can develop a predictable infarct volume within the MCA territory. In brief, a modified PE-50 tube is gently advanced from the external carotid artery (ECA) into the lumen of the internal carotid artery (ICA) until the tip of the catheter reaches the origin of the MCA. Through the catheter, a single homologous blood clot is placed at the origin of the MCA. To identify the success of MCA occlusion, regional cerebral blood flow was monitored, neurological deficits and infarct volumes were measured. The techniques presented in this paper should help investigators to overcome technical problems for establishing this model for stroke research.     

开放翼腭动脉改良制备大鼠自体血栓脑梗死模型比较

目的：利用大鼠自体血栓,在开放翼腭动脉（ pterygopalatine artery,PPA）的情况下堵塞其大脑中动脉,造成大脑中动脉远端供血区的脑梗死模型。方法开放PPA,结扎颈外动脉（ external carotid artery,ECA）,将栓子通过颈总动脉（common carotid artery,CCA）血流将栓子冲大脑中动脉（middle cerebral artery,MCA）远端,造成梗死模型,按Bederson评分对其神经功能进行评分,TTC染色确定梗死体积。结果两手术组模型比较,评分均升高,且出现白色梗死区,经统计检测分析无明显差异。结论开放PPA大鼠自体血栓制造脑梗死模型可缩短手术时间,降低死亡率。     

星形胶质细胞糖原动员改善大脑缺血再灌注损伤的研究

摘要 目的：探讨星形胶质细胞糖原动员是否对大脑缺血再灌注损伤有神经保护作用。方法：研究构建了星形胶质细胞特异性糖原分解代谢关键酶糖原磷酸化酶（Glycogen phosphorylase, GP）过表达转基因小鼠（GFAP-GP）,并通过免疫荧光染色对GP的含量进行验证。在小鼠大脑中动脉梗死/再通模型中,利用GFAP-GP小鼠促进再灌注后累积糖原的分解（糖原动员）,通过三苯基氯化四氮唑（Triphenyl tetrazolium chloride, TTC）染色分析再灌注后GFAP-GP小鼠的脑梗死面积,Corner test和Grid-walking test检测再灌注后GFAP-GP小鼠的神经行为学功能。结果：GFAP-GP小鼠中GP的含量发生了明显的增加,再灌注后GFAP-GP小鼠与野生型小鼠相比,脑糖原含量明显降低,梗死明显减少,肢体感觉与运动功能明显改善。结论：星形胶质细胞糖原动员可改善大脑缺血再灌注损伤。     

高压氧预处理对大鼠脑缺血再灌注损伤的保护作用及对其海马BDNF和GDNF基因表达的影响

目的:探讨高压氧预处理(Hyperbaric oxygen preconditioning, HBO-PC)对大鼠脑缺血再灌注损伤的保护作用及对其海马脑源性神经营养因子(brain-derived neurotrophic factor, BDNF)、胶质细胞源性神经营养因子(glialcellline-derivedneurotrophicfactor,GDNF)基因表达的影响。方法:将32只SD雄性大鼠随机分为对照组(Sham组)、高压氧对照组(HBO组)、模型组(MCAO组)、高压氧预处理+模型组(HBO+MCAO组),对HBO组和HBO+MCAO组连续给予高压氧预处理5天,随后对MCAO组和HBO+MCAO组进行右侧颈内动脉栓线术,建立大脑中动脉闭塞(middle cerebral artery occlusion, MCAO)模型,其他两组行假手术,于术后第7天对各组大鼠进行Morris水迷宫行为学检测和神经功能评分,检测结束后处死大鼠,进行神经功能缺损评分及氯化三苯基四氮唑(2,3,5-triphenyltetrazolium chloride, TTC)染色;通过蛋白免疫印迹法(Western Blot)检测大鼠海马组织BDNF和GDNF的基因表达情况。结果:(1)神经功能评分提示:Sham组和HBO组均未出现神经功能障碍,MCAO组大鼠出现明显的神经功能障碍,MCAO+HBO组神经功能评分明显高于MCAO组(P0.05)。(2)TTC检测提示:Sham组和HBO组脑组织损伤一侧均未出现梗死灶,MCAO组出现较大的梗死面积比(25.45±8.75)%,MCAO+HBO组的梗死面积比(18.84±10.55)显著小于MCAO组,差异具有统计学意义(P 0.05)。(3)Western Blot检测显示:MCAO组BDNF与GDNF基因表达水平显著低于Sham组和HBO组,差异具有统计学意义(P 0.05),而MCAO+HBO组可以逆转这一效应,差异具有统计学意义(P 0.05)。结论:高压氧预处理可以通过调节BDNF、GDNF基因表达,改善MCAO模型大鼠神经功能和认知水平,发挥神经保护作用。     

毛蕊异黄酮通过抑制calpain-1的表达发挥抗脑缺血再灌注损伤的研究

目的:探讨毛蕊异黄酮抗脑缺血再灌注损伤的作用是否与抑制calpain-1的表达有关。方法:将SD大鼠随机分为假手术组、模型组以及药物组,采用线栓法建立大鼠大脑中动脉阻断(MCAO)模型,于缺血再灌注前30 min腹腔注射给予20 mg/kg毛蕊异黄酮或等体积的溶剂。再灌注24 h后,行神经功能学评分、脑梗死面积以及神经元凋亡检测;再灌注12 h、24 h时,采用免疫组化和蛋白印迹技术检测大鼠脑皮层calpain-1的表达。结果:与假手术组大鼠比较,MCAO模型组大鼠再灌注24 h后神经功能学评分、梗死面积、神经元凋亡率及calpain-1的表达均明显升高(P0.05),而毛蕊异黄酮能够降低模型组大鼠再灌注24 h后神经功能学评分、梗死面积、神经元凋亡率以及calpain-1的表达(P0.05)。结论:毛蕊异黄酮可能通过抑制calpain-1的表达发挥抗脑缺血再灌注损伤作用。     

颈总动脉周围交感神经网剥脱切除术治疗学龄前脑瘫患儿的疗效及对患儿认知状况的影响

目的:探讨颈总动脉周围交感神经网剥脱切除术治疗学龄前脑瘫患儿的临床效果及对患儿认知状况影响。方法:选取2014年12月~2016年12月我院收治的学龄前脑瘫患儿84例,根据治疗方式的不同分为观察组与对照组,每组42例。对照组给予常规非手术治疗,观察组给予颈总动脉周围交感神经网剥脱切除术治疗,两组患儿均进行为期24周的随访观察。观察和比较两组的综合功能改善情况,治疗前后发育商、智商以及C因子值水平的变化。结果:观察组综合功能改善总有效率为95.24%(40/42),显著高于对照组的78.57%(33/42)(P0.05)。治疗后24周,观察组患儿的发育商值为(84.5±11.3),显著高于对照组(62.2±12.4)(P0.05);观察组患儿的智商值为(80.7±11.4),显著高于对照组(67.3±12.1)(P0.05);观察组患儿的C因子值为(12.8±4.0),显著高于对照组(9.9±3.3)(P0.05)。结论:颈总动脉周围交感神经网剥脱切除术治疗学龄前脑瘫患儿的临床效果显著,可有效改善患儿的认知状况。     

Permanent Cerebral Vessel Occlusion via Double Ligature and Transection

Stroke is a leading cause of death, disability, and socioeconomic loss worldwide. The majority of all strokes result from an interruption in blood flow (ischemia) ¹. Middle cerebral artery (MCA) delivers a great majority of blood to the lateral surface of the cortex ², is the most common site of human stroke ³, and ischemia within its territory can result in extensive dysfunction or death ^1,4,5. Survivors of ischemic stroke often suffer loss or disruption of motor capabilities, sensory deficits, and infarct. In an effort to capture these key characteristics of stroke, and thereby develop effective treatment, a great deal of emphasis is placed upon animal models of ischemia in MCA.Here we present a method of permanently occluding a cortical surface blood vessel. We will present this method using an example of a relevant vessel occlusion that models the most common type, location, and outcome of human stroke, permanent middle cerebral artery occlusion (pMCAO). In this model, we surgically expose MCA in the adult rat and subsequently occlude via double ligature and transection of the vessel. This pMCAO blocks the proximal cortical branch of MCA, causing ischemia in all of MCA cortical territory, a large portion of the cortex. This method of occlusion can also be used to occlude more distal portions of cortical vessels in order to achieve more focal ischemia targeting a smaller region of cortex. The primary disadvantages of pMCAO are that the surgical procedure is somewhat invasive as a small craniotomy is required to access MCA, though this results in minimal tissue damage. The primary advantages of this model, however, are: the site of occlusion is well defined, the degree of blood flow reduction is consistent, functional and neurological impairment occurs rapidly, infarct size is consistent, and the high rate of survival allows for long-term chronic assessment.