蛋白激酶B信号通路的干预在慢性脑低灌注大鼠中的作用及对海马细胞凋亡的影响

目的探讨蛋白激酶B/糖原合成酶激酶3β(Akt/GSK3β)信号通路是否参与慢性脑低灌注(CCH)大鼠海马细胞凋亡过程。方法选择SD大鼠60只,随机分为假手术组、CCH组、LY294002组、胰岛素样生长因子1(IGF-1)组,每组15只,后3组制作大鼠CCH模型,LY294002组和IGF-1组分别以抑制剂LY294002及激动剂IGF-1进行干预。采用TUNEL检测海马细胞凋亡;Western blot法检测Akt、GSK3β、磷酸化Akt(P-Akt)和磷酸化GSK3β(P-GSK3β)表达。结果与假手术组比较,CCH组、LY294002组及IGF-1组细胞凋亡水平均升高(P<0.05);与CCH组比较,LY294002组细胞凋亡数明显增高(20.33±1.52 vs 15.00±1.00,P<0.05),而IGF-1组细胞凋亡数降低(12.00±1.73 vs 15.00±1.00,P<0.05)。与假手术比较,CCH组和IGF-1组P-Akt,P-GSK3β均明显增高(P<0.05),而LY294002组无明显变化(P>0.05);与CCH组比较,IGF-1组P-Akt,P-GSK3β表达量均升高(P<0.05);LY294002组均降低(P<0.05)。结论 Akt/GSK3β信号通路参与CCH大鼠海马细胞凋亡过程,上调该通路Akt与GSK3β这2种蛋白的磷酸化表达水平,可能是拮抗这种细胞凋亡方式之一。     

米诺环素对慢性脑低灌注大鼠海马神经元β位点剪切酶1和β淀粉样蛋白表达的影响

目的观察不同剂量米诺环素对慢性脑低灌注大鼠海马神经元β位点剪切酶1(BACE1)和β淀粉样蛋白(Aβ)表达的影响。方法选择SD大鼠144只,随机分为假手术组、对照组、慢性脑低灌注组(模型组)、米诺环素低剂量组、中剂量组、高剂量组,每组24只。采用双侧颈总动脉永久结扎建立大鼠慢性脑低灌注模型,低、中、高剂量组在慢性脑低灌注模型的基础上分别给予5mg/(kg·d)、50mg/(kg·d)、500mg/(kg·d)的米诺环素连续灌胃。观察时间点分别为造模后1、2、3个月,采用免疫组织化学法检测海马CA1区神经元BACE1和Aβ表达。结果模型组1、2、3个月BACE1和Aβ表达较假手术组、对照组、低剂量组、中剂量组、高剂量组明显增加(P<0.05)。高剂量组2、3个月BACE1表达较低剂量组明显降低[(1.40±1.77)个/视野vs(10.50±4.83)个/视野,(1.25±1.24)个/视野vs(12.35±2.57)个/视野,P<0.05],3个月BACE1表达较中剂量组明显降低[(1.25±1.24)个/视野vs(12.00±1.02)个/视野,P<0.05]。结论米诺环素能抑制慢性脑低灌注大鼠海马神经元BACE-1和Aβ表达,高剂量米诺环素对BACE-1抑制作用明显。     

LncRNA H19通过PI3K/Akt通路对海人酸致癫痫大鼠海马神经细胞自噬的影响

目的:探讨长链非编码RNA(LncRNA)H19通过磷脂酰肌醇3-激酶/丝氨酸/苏氨酸蛋白激酶B(PI3K/Akt)通路对海人酸致癫痫大鼠海马神经细胞自噬的影响。方法:将50只SD大鼠随机分为对照组、模型组、NC组(空载体)、LncRNA H19-shRNA组、LncRNA H19-shRNA+LY294002组(10μL、1μg/μL PI3K特异性抑制剂LY294002),每组10只。颈内皮下注射海人酸构建癫痫大鼠模型,造模成功后,对各组大鼠海马CA1区注射相应剂量LncRNA H19-shRNA、空载体、LY294002,观察大鼠行为学变化并检测大鼠脑电图;实时荧光定量聚合酶链式反应(qRT-PCR)检测大鼠海马组织中LncRNA H19表达水平;苏木精-伊红(HE)及Nissl染色观察大鼠海马神经元损伤情况;透射电镜观察海马神经元自噬情况;免疫组化法及蛋白免疫印迹法(Western Blot)检测大鼠海马组织Beclin-1、LC3蛋白表达情况。结果:对照组大鼠脑电图波形正常、无癫痫发作;与对照组比较,模型组大鼠脑电图出现高幅高频波形,癫痫发作,LncRNA H19表达水平、神...     

促红细胞生成素对血管性痴呆大鼠认知功能及存活素和血管内皮生长因子表达的影响

目的观察促红细胞生成素(EPO)对血管性痴呆(VaD)大鼠认知功能及海马CA1区锥体细胞存活素、血管内皮细胞生长因子(VEGF)表达的影响。方法选择雄性Wistar大鼠144只,随机分为假手术组、VaD组和EPO组,每组48只。改良Pulsinelli四血管阻断法制备VaD大鼠模型。分别于术后1、2、4、8周4个时间点采用HE染色观察海马CA1区锥体细胞形态变化,免疫组织化学法及蛋白免疫印迹法检测海马CA1区存活素、VEGF的表达,Morris水迷宫对各组大鼠进行学习记忆功能的检测。结果与假手术组比较,VaD组和EPO组海马CA1区神经元结构受损,神经元密度明显减少[(18.56±3.15)102 mm2,(22.28±2.91)102 mm2 vs(28.89±4.08)102 mm2,P<0.05];VaD组和EPO组海马CA1区各个时间点存活素、VEGF蛋白表达均增加,于4周达峰值后逐渐下降,以EPO组更显著(P<0.05);VaD组和EPO组大鼠术后1、2、4、8周逃避潜伏期明显延长、跨越目标象限时间明显缩短(P<0.05)。结论腹腔注射EPO可促进海马CA1区锥体细胞存活素、VEGF的表达,从而一定程度上改善大鼠的认知功能。     

IGF-1和LY294002在大鼠脑缺血再灌注损伤中的相互作用机制

目的 探究胰岛素样生长因子(IGF)-1和LY294002在大鼠脑缺血再灌注损伤中对磷脂酰肌醇-3激酶(PI3K)和β-连环蛋白(catenin)的影响。方法 采用两血管阻断加硝普钠降压法制作大鼠血管性痴呆模型，将48只健康雄性SD大鼠随机分为4组：假手术组(S组)、脑缺血再灌注组(I/R组)、脑缺血再灌注+抑制剂LY294002后处理组(LY组)、脑缺血再灌注+IGF-1后处理组(IGF-1组)。应用HE染色检测大脑皮质和海马组织形态变化，穿梭箱测试各组大鼠的认知功能。应用免疫组织化学染色法分别检测各组大鼠皮质和海马PI3K和β-catenin表达情况。结果 相较于S组，I/R组脑组织损伤严重，组织学变化明显，PI3K和β-catenin表达明显增高(P<0.05);LY组PI3K和β-catenin的表达较I/R组表达明显减少(P<0.05)。IGF-1组组织学变化减轻，PI3K和β-catenin的表达量明显较I/R组和LY组增加(P<0.05)。结论 在脑缺血再灌注损伤中，IGF-1促进缺血皮质和海马神经元的存活，可以激活缺血性脑损伤中的PI3K/β-cate...     

下调PTEN对血管性痴呆大鼠海马神经元CREB的调节作用

目的探讨PTEN基因对血管性痴呆大鼠海马神经元CREB表达的影响机制。方法 30只大鼠随机分为正常组、AdR-siPTEN干预组、AdRFP阴性对照组,海马CA1区局部注射AdR-siPTEN腺病毒后2 d,采用双侧颈总动脉永久性结扎(2-VO)法建立血管性痴呆模型,4 w后应用HE染色检测神经元的损伤,RT-PCR和免疫组织化学检测CA1区Akt、CREB mRNA的表达。结果海马部位有PTEN基因红色荧光蛋白表达,并有PTEN基因的mRNA表达量明显下降(P0.01);HE染色显示,AdR-siPTEN组海马神经元损伤和变性程度明显轻于AdRFP阴性对照组大鼠;RT-PCR和免疫组化染色结果显示,与AdRFP组相比,AdR-siPTEN治疗组CA1区Akt、CREB的mRNA和蛋白表达水平显著升高(P0.05)。结论下调PTEN基因可通过Akt增加CREB的表达,从而改善血管性痴呆大鼠神经元突触可塑性,达到减轻神经元损伤、提高学习记忆和神经保护的目的 。     

卡配因I-细胞周期依赖性蛋白激酶5通路在血管性痴呆小鼠海马中的变化

目的 观察脑缺血-再灌注导致的血管性痴呆小鼠不同时间点海马组织卡配因I(Calpain I)-细胞周期依赖性蛋白激酶5(Cdk5)通路表达的变化.方法 雄性昆明小鼠160只,随机分为假手术组(n=65)和模型组(n=95).采用双侧颈总动脉反复缺血-再灌注的方法 制备血管性痴呆(VD)模型.术后第4周和第6周应用水迷宫实验进行行为学测试,免疫组化观察海马CA1区Calpain I的表达,RT-PCR观察Cdk5的mRNA表达,Western-blot 检测Cdk5的蛋白表达.结果 术后第4周和6周时模型组小鼠的学习、记忆成绩均明显劣于假手术组小鼠(P＜0.05).术后第4周模型组海马CA1区神经元Calpain I表达的平均光密度值(0.090 0±0.010 0)较假手术组(0.033 2±0.004 3)显著增高(P＜0.05),Cdk5 mRNA表达(0.91±0.07)较假手术组(0.35±0.02)显著增高(P＜0.05);术后第6周模型组海马Calpain I表达的平均光密度值(0.104 0±0.008 4)较假手术组(0.032 7±0.004 5)显著增高(P＜0.05),Cdk5 mRNA表达较假手术组显著增高(0.80±0.07 vs 0.53±0.05,P＜0.05).结论 Calpain I-Cdk5通路参与了脑缺血-再灌注后小鼠VD的发生.     

天麻乙酸乙酯提取物对血管性痴呆大鼠海马CA1区锥体细胞的影响

目的观察天麻乙酸乙酯提取物对血管性痴呆模型大鼠海马CA1区锥体细胞的影响。方法采用双侧颈总动脉永久性结扎法,造成慢性脑灌注不足所致SD大鼠血管性痴呆模型。造模6周后,40只大鼠随机分为5组,假手术组、模型组、尼莫地平组、天麻乙酸乙酯提取物高剂量组(高剂量组)和天麻乙酸乙酯提取物低剂量组(低剂量组),每组8只。给药3周后,HE染色检测海马锥体细胞的变化。结果与假手术组比较,模型组大鼠海马CA1区锥体细胞数目明显减少(P<0.01);与模型组比较,尼莫地平组和高剂量组大鼠海马CA1区锥体细胞数目明显增多(P<0.01),低剂量组大鼠海马CA1区锥体细胞数目无明显变化(P>0.05)。结论天麻乙酸乙酯提取物能改善血管性痴呆大鼠脑组织海马CA1区锥体细胞的病理改变。     

穴位埋线对血管性痴呆大鼠海马CA1区p53蛋白表达的影响

目的观察穴位埋线对血管性痴呆(VD)大鼠海马CA1区p53蛋白表达的影响。方法取SD大鼠随机分成假手术组、VD模型组、穴位埋线组、尼莫地平组,采用改良的Pulsinelli四血管闭塞法(4-VO)建立VD大鼠模型,两个治疗组分别施行穴位埋线和尼莫地平治疗,连续15 d。水迷宫行为学测试后,断头处死大鼠,采集海马CA1区,用免疫组织化学法检测其p53表达,并取大脑皮质做冠状位病理切片进行HE染色,观察并比较各组大鼠海马CA1区p53和大脑皮质神经元损伤程度。结果假手术组海马CA1区未见p53阳性细胞,穴位埋线组及尼莫地平组海马CA1区p53阳性细胞平均灰度值均明显高于VD模型组(P<0.05),大脑皮质神经元的损伤和变性减轻且数量增加。结论穴位埋线可明显降低海马CA1区p53蛋白的表达,抑制VD大鼠脑损伤引起的细胞凋亡,对脑组织起保护作用,这可能是其治疗VD的作用机制之一。     

丹酚酸A对大鼠脑缺血再灌注损伤后胞浆型磷脂酶A2表达的影响及机制研究

目的探讨丹酚酸A对大鼠脑缺血再灌注损伤后胞浆型磷脂酶A2(cytosolic phospholipase A2,cPLA2)表达的影响及其机制。方法将SD大鼠65只,随机分为对照组,模型组、丹酚酸A组和联合组(LY294002+丹酚酸A)。分别于再灌注后0、8、24、48h取梗死脑组织,用TUNEL检测脑细胞凋亡,免疫组织化学检测cPLA2表达,Western blot检测蛋白激酶B(Akt)、磷酸化Akt在脑组织表达水平。结果模型组和联合组0、8、24、48h海马CAl区TUNEL阳性细胞和cPLA2表达较对照组明显增高,脑组织磷酸化Akt表达较对照组明显降低(P0.05)。丹酚酸A组0、8、24、48h脑组织磷酸化Akt表达较模型组明显增高,TUNEL阳性细胞和cPLA2表达较模型组明显降低[(10.1±5.3)个/mm~2 vs(12.8±4.7)个/mm~2、(14.6±6.2)个/mm~2 vs(30.1±7.5)个/mm~2、(19.7±6.5)个/mm~2 vs(73.8±11.4)个/mm~2、(22.8±9.6)个/mm~2 vs(94.6±15.2)个/mm~2,(13.6±3.1)个/mm~2 vs(41.3±3.6)个/mm~2、(14.8±4.7)个/mm~2 vs(62.5±6.9)个/mm~2、(16.6±7.1)个/mm~2 vs(72.3±9.6)个/mm~2、(17.0±5.3)个/mm~2 vs(83.2±11.7)个/mm~2,P0.05]。结论丹酚酸A通过Akt信号通路,降低脑缺血再灌注后脑组织中cPLA2表达,减少脑细胞凋亡,发挥细胞保护作用。     

2011年ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS颅外颈动脉和椎动脉疾病患者处理指南

导言医疗专业人员在对与疾病检测、处理或预防中使用的药物、装置和操作相关的证据的严格评价中扮演的核心角色是十分必要的。对涉及这些疗法和操作的绝对和相对益处和风险的现有资料进行适当和严格的专业分析,可通过将资源集中于最有效的治疗策略,从而改善治疗效果、优化患者转归和合理控制成本。这些资料的一种重要应用是制定临床实践指南,后者进而能为其他各种应用,如绩效评价、合理应用标准、临床决策支持工具和质量改进工具提供依据。     

Development of a monoclonal antibody capable of differentiating platelet PLA1/PLA1, PLA1/PLA2 and PLA2/PLA2 genotypes

A monoclonal antibody, LK-4, has been developed which distinguishes platelet PLA1/PLA1, PLA1/PLA2 and PLA2/PLA2 genotypes on platelet glycoprotein GPIIIa of Triton-solubilized platelet extracts. An ELISA assay has been developed which traps GPIIIa with Concanavalin A, enriching the platelet extract for the PLA antigens. A second monoclonal antibody, DEK-10, which reacts equally with GPIIIa of PLA1/PLA1 and PLA2/PLA2 platelet extracts is employed as an internal standard to correct for individual differences in GPIIIa content, GPIIIa extracted by Triton X-100 and GPIIIa trapped with Concanavalin A. This ELISA assay clearly differentiated 11 different PLA1/PLA1 subjects from eight PLA2/PLA2 women with a history of neonatal alloimmune thrombocytopenia as well as six unrelated obligate heterozygotes and should be useful in evaluating the PLA genotype of pregnant women and their families.     

The Response of W/Wv and Sl/Sld Anaemic Mice to Haemopoietic Stimuli

Summary: The percentage of haem-containing nucleated RBC precursor cells in marrows and spleens of W/W^v and Sl/Sl^d anaemic mice increased in response to hypoxia produced by reduced pressure, red-cell loss, or red-cell destruction by phenylhydrazine. The response in the spleens of W/W^v mice occurred several days later than the marrow response, in contrast to normal or Sl/Sl^d mice in which the marrow and spleen responses occurred simultaneously. These responses were also simultaneous in W/W^v mice whose anaemia had been cured by an injection of normal stem cells. After RBC destruction by phenylhydrazine the duration and degree of tissue hypoxia necessary to stimulate the Sl/Sl^d response varied widely among individual Sl/Sl^d mice. In Sl/Sl^d mice with anaemias alleviated by implants of intact normal spleens, most erythropoiesis was contained within these normal spleen grafts.
Polycythaemic W/W^v and Sl/Sl^d anaemic mice gave defective responses to erythropoietin; the defect was not caused by delayed erythroid maturation. Serum samples from anaemic mice responding to RBC destruction by phenylhydrazine contained high concentrations of erythropoietin in quantities inversely proportional to the donor's PCV (packed cell volume), but did not contain any factors, other than erythropoietin, to stimulate erythropoiesis in polycythaemic Sl/Sl^d anaemic mice.     

Immunochemical characterization of the new platelet alloantigen system Bra/Brb

We report the immunochemical characterization of the new platelet-specific alloantigens Bra and Brb. Bra antibodies were from mothers of children with neonatal alloimmune thrombocytopenia (NAIT), and anti-Brb was found in the serum of a polytransfused patient. By radioimmunoprecipitation, anti-Bra and anti-Brb precipitated two proteins with apparent relative molecular masses in sodium dodecyl sulphate-polyacrylamide gel electrophoresis of 155,000 and 130,000 under non-reduced conditions, and of 165,000 and 148,000 under reduced conditions. In two-dimensional polyacrylamide gel electrophoresis, the two bands moved with isoelectric points ranging from 5.2 to 5.4 and from 4.5 to 4.7, respectively. These features fulfil previously defined criteria for platelet membrane glycoproteins (GP) Ia and IIa. The results were supported by data obtained by an assay employing monoclonal antibody (mab)-specific immobilization of platelet antigens (MAIPA). By this technique, Bra and Brb antigens could be immobilized by mabs specific for the GP Ia/IIa complex (mab Gi 14) or a mab specific for the very late antigen-2 (mab 12 F1), but not by a mab specific for GP IIb/IIIa complex (mab Gi3). Furthermore, platelets from a thrombasthenic patient with complete absence of GP IIb/IIIa expressed the Brb antigen normally as shown in MAIPA; this antigen could be immunoprecipitated with anti-Brb and was identical to that of normal platelets. This confirms that the antigens of the Br system are not associated with the GP IIb/IIIa complex. By direct binding studies using mabs Gi3 and Gi14, we calculated that 51,500 +/- 3900 molecules of anti-GP IIb/IIIa and 6,470 +/- 500 molecules of anti-GP Ia/IIa were bound per platelet at saturation. Our results provide evidence for the first platelet-specific alloantigen system residing on the GP Ia. The difficulty in detecting anti-Bra and anti-Brb by direct binding assays may be related to the small number of GP Ia/IIa complexes on platelets.     

Effects of recombinant human erythropoietin on anaemic W/Wv and SI/SId mice

The effects of recombinant human erythropoietin (rHuEPO) on anaemic W/Wv and Sl/Sld mice were investigated. rHuEPO was injected every day for a week in doses up to 86,000 iu/kg. Wv/+ and Sld+ mice, which have genetically a weak anaemia, received 17 or 86 iu/kg of rHuEPO and showed dose-dependent increases in haemoglobin, PCV, RBC and reticulocytes to the same extent as that in normal mice. W/Wv mice also showed increases in the haematological parameters in response to 8600 iu/kg of rHuEPO but the dose was much higher than that for normal mice. A reticulocyte increase in W/Wv mice appeared later than in normal mice and was not sustained for 2 weeks even though the rHuEPO treatment was continued. Sl/Sld mice, however, did not show any significant haematological effect from doses up to 86,000 iu/kg. In both W/Wv and Sl/Sld mice receiving 8600 and 86,000 iu/kg of rHuEPO, respectively, an increase in splenic or bone marrow CFU-E was observed regardless of the defect in their haemopoietic systems. The plasma erythropoietin (EPO) level in W/Wv and Sl/Sld mice was inversely correlated with the haemoglobin, indicating that EPO production was not influenced by the haemopoietic defect and was regulated by the hypoxic properties of the anaemia. These results indicate that a large dose of exogenous rHuEPO is effective for the anaemia in W/Wv mice caused by a stem cell defect but not for the anaemia in Sl/Sld mice caused by a defective microenvironment.