The inhibitory effects of cholalic acid and hyodeoxycholalic acid on the expression of TNFα and IL-1β after cerebral ischemia in rats

Previous studies have shown that Qing Kai Ling, a traditional Chinese medicine, was able to effectively prevent the inflammation from cerebral ischemia (Chen et al., 2002). The cholalic acid and hyodeoxycholalic acid (cholalic acid mixture) was major active components in Qing Kai Ling. To study the effects of cholalic acid mixture on the damage cascade of cerebral ischemia, rat model of focal cerebral ischemia was established by permanent occlusion of left middle cerebral artery. We found that the administration of cholalic acid mixture could reduce the ischemic infarct size after 24 h of ischemia, and cholalic acid mixture could be detected in cerebrospinal fluid after 2h of administration. We also found that the concentrations of tumor necrosis factor-alpha and interlukin-1beta in rat brain were significantly lower when compared to the untreated animals after 12 h and 24 h of ischemia. The concentrations of von Willebrand factor and neuron specific enolase in the plasma were remarkably decreased in cholalic acid mixture treated animals than in the untreated ones after 12h of ischemia. Our results suggested that cholalic acid mixture is able to decrease the expression of inflammation factors including tumor necrosis factor-alpha and interlukin-1beta after focal cerebral ischemia. These two authors contribute equally to the paper.     

后适应对大鼠脑缺血神经细胞凋亡和内皮型一氧化氮合酶与诱导型一氧化氮合酶的影响

目的：研究缺血耐受（后适应和预适应）对脑缺血再灌注神经细胞凋亡及内皮型一氧化氮合酶（eNOS）和诱导型一氧化氮合酶（iNOS）蛋白表达的影响。方法：50只雄性SD大鼠随机分为假手术组（sham）、脑缺血再灌注模型组（MCAO）、预适应组（MCAO＋preconditioning）、后适应组（MCAO＋postconditioning）和尼莫地平组（MCAO＋nimodipine），每组10只大鼠。预适应组大鼠在MCAO前24h，双侧颈总动脉夹闭2min，再灌注20min，循环两次。后适应组大鼠在脑缺血再灌注开始时，再灌注20s，栓塞20s，循环3次。大鼠大脑中动脉阻断1．5h，再灌注24h。用TUNEL法和免疫组化染色法分别检测缺血半暗带凋亡细胞和iNOS、eNOS蛋白表达。结果：与MCAO组比较，后适应组大鼠脑缺血半暗带的凋亡细胞显著减少，eNOS蛋白表达显著增加，iNOS蛋白表达显著减少，差异有统计学意义（P〈0．05）。结论：缺血后适应能诱导脑缺血耐受，对脑缺血／再灌注损伤产生保护作用，其保护作用与促进eNOS蛋白的表达，抑制iNOS蛋白的表达有关。     

脑心通抑制脑缺血诱导的内质网凋亡通路

目的观察脑心通对大鼠缺血脑组织内质网凋亡通路caspase-12表达的影响,探讨其对大鼠局灶性脑缺血损伤的保护机制。方法采用线栓法制备大鼠局灶性脑缺血模型。大鼠随机分为假手术组、缺血组以及缺血后脑心通治疗组（n=30）,应用组织学观察、免疫组织化学方法及半定量RT-PCR检测缺血不同时段caspase-12表达变化。结果脑缺血6 h caspase-12转录表达增加,12 h达高峰,24h下降。脑心通治疗组与缺血组同时间在相同脑区比较caspase-12转录表达明显减少。假手术组caspase-12无表达。结论脑心通可抑制脑缺血所致的caspase-12凋亡通路,减轻脑缺血造成的损害。     

芪参胶囊对大鼠局灶性脑缺血再灌注损伤的保护作用

目的研究芪参胶囊对大鼠局灶性脑缺血再灌注损伤的保护作用。方法用线栓法建立大鼠局灶性脑缺血模型,大鼠于缺血1h再灌注2h断头取脑,检测大脑组织Ca2 -ATPase,Na ,K -ATPase,NOS活性和NO,水的含量及大脑皮层神经元内游离钙离子浓度,行为学评价及梗死面积,常规石蜡切片,HE染色,作病理学检查。结果芪参胶囊显著降低缺血再灌注后大脑皮层神经元内游离钙离子浓度及大脑组织NOS活性,NO的含量和水肿程度及梗死面积;显著增强Ca2 -ATPase,Na ,K -ATPase的活性;病理学检查显示芪参胶囊能明显减轻脑水肿及神经元坏死程度。结论芪参胶囊对大鼠局灶性脑缺血再灌注损伤有明显保护作用。     

氧化苦参碱对大鼠局灶性脑缺血损伤的保护作用及其抑制凋亡的作用机制

目的探讨氧化苦参碱(oxymatrine,OMT)对大鼠局灶性脑缺血损伤的保护作用及其抑制凋亡的作用机制。方法采用大鼠永久性大脑中动脉阻塞(permanent middle cer-ebral artery occlusion,pMCAO)方法,建立脑缺血模型,大鼠pMCAO术后通过腹腔给予OMT(30、60、120 mg.kg-1),以脑梗死体积、脑含水量和行为学症状等指标评价OMT对脑缺血的神经保护作用。通过HE染色方法观察OMT对缺血皮层神经细胞的形态变化以及数目的影响;应用Westernblot法检测OMT对缺血皮层Caspase-3、Bcl-2、Bax蛋白水平的表达。结果在大鼠局灶性脑缺血体内模型中,OMT(30、60、120 mg.kg-1)可明显减小脑梗死体积、脑含水量和改善行为学体征(P<0.01)。HE染色结果提示:OMT可明显增加神经细胞的存活率改善神经细胞的形态。Western blot结果显示:与假手术组相比,大鼠pMCAO后3、6、12、24 h,缺血皮层Caspase-3、Bax蛋白的表达水平在3 h开始上升,24 h达到峰值;而Bcl-2的表达水平在3h开始下降,24 h降到最低。给予OMT后可下调pMCAO大鼠缺血皮层中Caspase-3、Bax蛋白,上调Bcl-2蛋白。结论氧化苦参碱对脑缺血损伤有直接的神经保护作用,其机制可能通过上调Bcl-2及下调Bax、Caspase-3蛋白水平抑制凋亡发生。     

黄体酮对大鼠局灶性脑缺血后血脑屏障的保护

目的研究黄体酮对局灶性脑缺血后血脑屏障的保护作用。方法将48只老年大鼠随机分为假手术组（Sham）、脑缺血组（Ischemia）、安慰剂组（Vehicle）、黄体酮组（PROG）,每组12只,其中6只用来进行梗死体积测定,6只用来测定血脑屏障连接粘附分子-A（junctional adhesion molecule-A,JAM-A）。利用大脑中动脉栓线阻断法（middle cerebral artery occlusion,MCAO）造成大鼠局灶性脑缺血损伤模型,通过氯化四唑（tetrazolium chloride,TTC）染色测定梗死体积,应用Western blot技术检测JAM-A蛋白水平的表达。结果黄体酮能有效减少脑梗死体积和血脑屏障的破坏;黄体酮能在蛋白水平阻断JAM-A的下调。结论黄体酮能通过阻断JAM-A的下调减少脑缺血后血脑屏障的破坏,减小脑梗死体积。     

乐尔脉胶囊对大鼠缺血再灌注后期大脑皮层细胞凋亡的干预作用

目的:研究乐尔脉胶囊(LEM)对大鼠局灶性脑缺血2h再灌注30d后所致大脑皮层神经细胞凋亡的干预作用。方法:以线栓阻断(MCAO)法制备大鼠右侧大脑中动脉缺血再灌注模型,分为假手术、模型、盐酸氟桂利嗪及LEM高、低剂量组;应用免疫组化、凋亡细胞原位末端标记法(TUNEL)与逆转录聚合酶链反应(RT-PCR)技术检测大鼠大脑细胞凋亡和细胞凋亡相关基因产物(Fas)、凋亡促进基因(Bax)mRNA的表达,并进行图像分析。结果:模型组凋亡细胞主要位于缺血侧大脑皮层缺血边缘区(半暗带区);缺血侧大脑皮层Fas、Bax mRNA的表达在缺血再灌注30d后仍有升高;LEM组Fas、Bax mRNA的表达显著低于模型组(P<0.01),凋亡细胞数也显著低于模型组(P<0.01)。LEM组可明显降低损伤侧脑组织Fas、Bax mRNA的表达,抑制细胞凋亡,减轻缺血再灌注对大鼠大脑皮层神经细胞的损伤。结论:LEM对大鼠脑缺血再灌注30d后的细胞凋亡有一定的干预作用。     

卡托普利对大鼠局灶性脑缺血再灌注损伤后炎症反应的影响

目的观察血管紧张素转化酶抑制药卡托普利对大鼠局灶性脑缺血再灌注损伤后炎症反应的影响。方法采用血管内栓线阻断法制备大鼠局灶性脑缺血再灌注损伤模型,于脑缺血1 h、再灌注24 h后测定脑组织中髓过氧化物酶(MPO)活性,免疫组织化学方法测定细胞间黏附分子(ICAM-1)表达。结果卡托普利可明显抑制MPO活性及ICAM-1的表达。结论卡托普利可抑制脑缺血再灌注损伤后炎症反应。     

大鼠脑缺血再灌注后血脑屏障超微结构的改变

目的：研究大鼠脑缺血再灌注后电镜超微结构血脑屏障的特异改变。方法：采用线栓法制成大鼠大脑中动脉闭塞（MCAO）局灶性缺血2h再灌注24h模型。利用电镜技术研究脑缺血再灌注后电镜超微结构血脑屏障的特异改变。结果：在脑微血管内皮细胞核固缩，内皮细胞连接间隙和通透性增加，有的可见连接内皮细胞的基质和基膜的完整性缺失，微血管周围胶质细胞的伪足肿胀、进行性退变，微血管腔狭窄。白毛细血管内皮细胞向管腔内伸出许多突起。结论：局灶性脑缺血再灌注后24h血脑屏障的超微结构改变，可能对血液和神经元之间的营养传递有益。这可能是代偿修复和血管再生的机制之一。     

醒脑静乳剂对脑缺血缺氧损伤的保护作用

目的观察醒脑静乳剂对脑缺血缺氧损伤的保护作用。方法采用小鼠断头法、吸入氮气法和大鼠大脑中动脉阻断（MCAO）法制造脑缺血缺氧模型。实验动物随机分成生理盐水（NS）对照组及醒脑静乳剂大、中、小3个剂量组及阳性药对照（醒脑静注射液）组,共5组,每组10只。分别观察醒脑静乳剂对小鼠断头张口喘气持续时间、氮气模型小鼠存活时间的影响和对MCAO模型大鼠神经行为学、脑梗塞百分率和脑组织乳酸脱氢酶（LDH）活性,丙二醛（MDA）含量的影响。结果醒脑静乳剂可明显延长小鼠断头后张口喘气动作的持续时间和氮气模型鼠的存活时间,降低或改善MCAO大鼠行为障碍、脑梗塞率,抑制脑组织LDH活性的下降和MDA含量的升高,并呈一定的剂量依赖性。结论醒脑静乳剂对缺血缺氧性脑损伤具有保护作用。     

Pranlukast reduces neutrophil but not macrophage/microglial accumulation in brain after focal cerebral ischemia in mice

AIM: To determine whether pranlukast, a cysteinyl leukotriene receptor-1 antagonist, exerts an anti-inflammatory effect on focal cerebral ischemia in mice. METHODS: Focal cerebral ischemia in mice was induced by permanent middle cerebral artery occlusion (MCAO). In addition to neurological deficits, infarct volume, degenerated neurons and endogenous IgG exudation, we detected accumulation of neutrophils and macrophage/microglia in the ischemic brain tissue 72 h after MCAO. Pranlukast was ip injected 30 min before and after MCAO. RESULTS: Pranlukast significantly attenuated neurological deficits, infarct volume, neuron degeneration and IgG exudation. Importantly, pranlukast (0.01 and 0.1 mg/kg) inhibited myeloperoxidase-positive neutrophil, but not CD11b-positive macrophage/microglial accumulation in the ischemic cortical tissue. CONCLUSION: Pranlukast exerts an anti-inflammatory effect on focal cerebral ischemia in the subacute phase that is limited to neutrophil recruitment through the disrupted blood-brain barrier.     

补阳还五注射液对大鼠实验性脑缺血的影响

目的观察补阳还五注射液对大鼠不完全性脑缺血及局灶性脑缺血的影响。方法结扎双侧颈总动脉,建立大鼠急性不完全性脑缺血模型,观察补阳还五注射液静脉注射给药(10、5、2.5 g.kg-1)对大鼠脑含水量、脑指数及脑内伊文思兰渗出量的影响;结扎大鼠大脑中动脉建立局灶性脑缺血模型,连续腹腔给补阳还五注射液(10、5、2.5 g.kg-1)45 d,采用跳台实验观察大鼠出现学习记忆障碍的程度,并比较大脑的病理组织学变化。结果补阳还五注射液能显著抑制由结扎大鼠颈总动脉引起的脑含水量的增加,使脑指数趋于平衡,减轻脑水肿;可减少脑内伊文思兰的渗出量,降低缺血引起的脑毛细血管通透性的增加;能够改善由结扎大鼠大脑中动脉引起的学习记忆障碍和大脑细胞的损害。结论补阳还五注射液具有较好的对抗大鼠实验性脑缺血的作用。     

Montelukast, a cysteinyl leukotriene receptor-1 antagonist, dose- and time-dependently protects against focal cerebral ischemia in mice

Our previous studies showed that cysteinyl leukotriene receptor-1 (CysLT1) antagonist pranlukast has a neuroprotective effect on cerebral ischemia in rats and mice. However, whether the neuroprotective effect of pranlukast is its special action or a common action of CysLT1 receptor antagonists remains to be clarified. This study was performed to determine whether montelukast, another CysLT1 receptor antagonist, has the neuroprotective effect on focal cerebral ischemia in mice, and to observe its dose- and time-dependent properties. Permanent focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO). Montelukast was injected intraperitoneally either as multiple doses (once a day for 3 days and 30 min before MCAO) or as a single dose (at 30 min before, 30 min after, or 1 h after MCAO), respectively, and pranlukast and edaravone were used as controls. The neurological deficits, infarct volumes, brain edema, neuron density, and Evans blue extravasation in the brain were determined 24 h after MCAO. Pretreatments with multiple doses or a single dose of montelukast (0.1 and 1.0 mg/kg) before MCAO significantly attenuated all the ischemic insults. Post-treatment with a single dose of montelukast (0.1 and 1.0 mg/kg) at 30 min after MCAO also significantly decreased brain edema and infarct volume, but not neurological deficits. However, post-treatment with a single dose of montelukast at 1 h after MCAO had no significant effect. Pranlukast showed the same effects as montelukast, but edaravone attenuated the ischemic insults only with multiple doses before MCAO. Thus, montelukast has a dose- and time-dependent neuroprotective effect on permanent focal cerebral ischemia in mice, with an effective dose range of 0.1-1.0 mg/kg and a therapeutic window of 30 min. These findings further support the therapeutic potential of CysLT1 receptor antagonists in the treatment of cerebral ischemia at earlier phases.     

生姜对局灶性脑缺血模型大鼠的影响

目的研究生姜对局灶性脑缺血模型大鼠的影响。方法SD雄性大鼠随机分为假手术组、模型对照组、川芎嗪组、生姜汁高剂量组、中剂量组和低剂量组，开颅直接阻断大鼠一侧大脑中动脉造成局灶性脑缺血模型（MCAO），灌胃给药5d，积分法测定MCAO大鼠神经病学症状等级，避暗法测定被动性条件反射潜伏期和错误次数，氯化三苯基四氮唑（TFC）染色法测定大脑梗死面积。结果与假手术组比较，MCAO模型组大鼠出现明显的神经功能障碍，学习记忆能力降低，被动性条件反射潜伏期明显缩短，错误次数显著增多，脑组织出现明显的梗死灶；生姜汁能明显改善MCAO大鼠神经病学症状，延长被动性条件反射潜伏期及减少错误次数，提高记忆能力，显著缩小脑梗死面积，与模型对照组比较差异有统计学意义（P〈0．05）。结论生姜对大鼠局灶性脑缺血损伤具有显著的保护作用。     

大蒜素对大鼠局灶性脑缺血后热休克蛋白的影响

目的探讨大蒜素对大鼠局灶性脑缺血后热休克蛋白的影响。方法用线拴法建立大鼠大脑中动脉栓塞(MCAO)模型。50只大鼠随     

复方白花前胡液对大脑中动脉缺血再灌注大鼠 Caspase-3蛋白表达的影响

目的 :探索复方白花前胡液对大脑中动脉缺血再灌注大鼠Caspase 3蛋白表达的影响。方法 :线栓法制备大脑中动脉缺血再灌注大鼠模型 ,术后2 4、4 8、72h分别检测大鼠的神经功能缺损 ;并采用免疫组织化学法检测凋亡相关基因Caspase 3蛋白表达。结果 :MCAO R 2 4、4 8、72h后 ,所有动物都出现程度不同的运动障碍 ,且大鼠脑组织中Caspase 3蛋白表达显著升高 ,复方白花前胡液可明显改善大脑中动脉缺血再灌注大鼠的神经功能缺损症状 ,抑制大鼠Caspase 3蛋白表达水平。结论 :复方白花前胡液能有效抑制凋亡相关基因Caspase 3蛋白的表达 ,减轻或消除缺血级联反应中迟发性神经元死亡 ,复方白花前胡液是其治疗缺血性中风病的机理之一。     

苯海索对局灶性脑缺血-再灌注大鼠大脑皮质Ca2+含量、海马c-fos、c-sis基因表达的影响

目的观察苯海索对大鼠局灶脑缺血-再灌注损伤后大脑皮质Ca2 含量、海马c-fos、c-sis基因表达的影响.方法选用高血压大鼠制成大脑中动脉闭塞再灌注模型,大鼠于缺血1 h再灌注2 h断头取脑,用原位杂交技术观察海马c-fos、c-sis基因表达及荧光法测量大脑皮质钙离子的变化.结果苯海索可显著降低模型大鼠大脑皮质Ca2 含量,海马c-fos、c-sis基因表达.结论苯海索对大鼠局灶性脑缺血再灌注损伤有明显保护作用.     

辛伐他汀对大鼠脑缺血再灌注后脑组织NOS表达的影响

目的观察辛伐他汀对大鼠脑缺血再灌注后脑组织eNOS、nNOS和iNOS表达的影响。方法24只Wistar大鼠随机分为假手术组(Sham)、缺血再灌注IR组(IR)、辛伐他汀预处理高、低剂量组,每组6只。高剂量组和低剂量分别以阿伐他汀6mg/kg和1.5mg/kg连续灌胃7天。用线栓法制备大脑中动脉缺血再灌注模型,缺血2h,再灌注22h,应用免疫组化法检测脑组织中eNOS、nNOS和iNOS的表达。结果与缺血再灌注组比较,辛伐他汀低剂量组eNOS表达差异无显著意义(P>0.05),高剂量组eNOS表达显著增加(P>0.05);高剂量和低剂量组nNOS和iNOS的表达显著降低(P<0.01,P<0.05)。结论辛伐他汀预处理能抑制大鼠脑缺血再灌注后脑组织iNOS、nNOS的表达、上调eNOS表达。     

Down regulation of cyclooxygenase-2 is involved in delayed neuroprotection by ischemic preconditioning in rats

Aim: To examine whether the prostaglandins (PGs) pathway is involved in triggering delayed neuroprotection by ischemic preconditioning (IPC) and evaluate the effects of IPC on cyclooxygenase-2 (COX-2) expression following focal cerebral ischemia and reperfusion in rats. Methods: IPC was induced by 10min of saline infusion into the left internal carotid artery with the right common carotid artery clamped at the same time. Middle cerebral artery occlusion (MCAO) and reperfusion model was prodt:ced using intraluminal filament method. Results: IPC 48h priorto MCAO significantly reduced infarct area as compared with MCAO alone. A nonselective inhibitor of COX indomethacin (3mg/kg ip) applied 1h prior to or 1h after IPC failed to affect its protective effects. IPC had no direct effect on the cortex COX-2 mRNA and protein expression 72h later, but decreased the expression of COX-2 mRNA and protein following ischemia and reperfusion insult. Conclusion: PGs pathways was not involved in triggering delayed neuroprotection by IPC, and IPC induced down-regulation of COX-2 following focal cerebral ischemia and reperfusion in rats in vivo.     

法舒地尔预处理对大鼠脑缺血再灌注损伤细胞色素C和caspase-3表达的影响

目的研究法舒地尔对大鼠局灶性脑缺血再灌注损伤细胞色素C(CytC)和caspase-3蛋白表达的影响,探讨其脑保护机制。方法线栓法制作大鼠中动脉缺血再灌注损伤模型。成年雄性SD大鼠120只随机分成3组:假手术组(Sham组)、脑缺血再灌注模型组(Mod组)、法舒地尔干预组(Fas组),再分为再灌注3h、12h、24h和48h,以及TTC染色组5个亚组,每组8只大鼠。缺血再灌注后进行神经功能缺损评分(NDS),免疫组织化学方法检测脑组织中CytC蛋白、cas-pase-3的表达,TTC染色测量鼠脑梗死体积并计算百分比。结果①Sham组大鼠无神经功能缺损,NDS评分为0,TTC染色亦未见脑组织梗死;Mod组和Fas组大鼠均有明显的神经功能缺损,TTC染色亦可见明显的脑组织梗死;但与Mod组相比,Fas组神经功能缺损少、NDS评分低(P<0.01),脑梗死体积减小(P<0.05)。②与Sham组相比,脑缺血再灌注后,Mod组和Fas组大鼠脑组织CytC和caspase-3的表达显著升高(P<0.01),其中CytC表达高峰出现在12h,caspase-3表达高峰出现在24h;Fas组和Mod组间比较显示Fas组CytC和caspase-3的表达又显著低于Mod组(P<0.01)。结论①法舒地尔能减轻大鼠脑局灶性缺血再灌注引起的神经功能缺损,减小脑梗死体积。②部分抑制脑缺血再灌注引起的CytC和caspase-3表达增加可能是法舒地尔的脑保护机制之一。