盐酸多奈哌齐对拟VaD大鼠海马CA1区NR1及NR2B免疫组织化学表达的影响

目的探讨盐酸多奈哌齐对拟血管性痴呆大鼠海马神经元N-甲基-D-天门冬氨酸(NMDA)受体亚单位R1(NMDAR1,NR1)和R2B(NMDAR2B,NR2B)的免疫组织化学表达的影响。方法采用双侧颈总动脉反复夹闭、再通,并腹腔注射硝普钠法制备模型,用盐酸多奈哌齐溶液灌胃,Y-型迷宫试验观察其行为学改变,用免疫组织化学技术观测大鼠海马神经元NR1、NR2B的表达变化。结果盐酸多奈哌齐组大鼠海马CA1区NR1表达明显降低,与模型组比较有显著性差异(均P<0.01),与假手术组相比差异无显著性;NR2B表达较模型组明显增高(P<0.01),与假手术组比较无显著性差异。结论盐酸多奈哌齐有可能通过降低NR1的表达,提高海马NR2B的表达,从而改善拟血管性痴呆大鼠的学习、记忆成绩。     

大豆异黄酮对Alzheimer病大鼠认知功能及海马NR2B表达的影响

目的 研究大豆异黄酮对Alzheimer病（AD）大鼠模型认知功能及海马组织N-甲基-D-天（门）冬氨酸2B受体（NR2B）表达的影响。方法 60只大鼠随机分为模型组、低剂量大豆异黄酮组、高剂量大豆异黄酮组、雌激素组及对照组。采用p淀粉样蛋白25—35（Aβ25-35）双侧海马注射制作AD大鼠模型，对照组注射生理盐水。制模后相应地给予不同剂量大豆异黄酮及雌激素治疗18d，通过Morris水迷宫实验观察各组大鼠认知功能的变化，免疫组化法检测各组大鼠海马NR2B表达。结果 与对照组相比，模型组大鼠学习、记忆功能明显下降，海马NR2B表达明显降低（均P〈0.05）；大豆异黄酮及雌激素治疗后大鼠学习及记忆能力较模型组显著升高（均P〈0．05），高剂量组疗效优于低剂量组（均P〈0．05），且与雌激素组相比差异无显著性。与模型组相比，各治疗组大鼠海马NR2B的表达明显增加（均P〈0．05），各治疗组问差异无显著性。结论 大豆异黄酮具有雌激素样作用，通过上调海马NR2B的表达，改善大鼠的学习记忆功能，并具有剂量依赖性。     

戊四氮点燃癫癎大鼠空间学习记忆改变及海马NR2B表达

目的观察戊四氮点燃癫癎大鼠空间学习记忆功能变化及海马NMDA2型受体(NR2)B亚单位(NR2B)表达,探讨二者的关系及PTZ致癎大鼠认知障碍发生的分子机制。方法采用戊四氮(PTZ)慢性癫癎(CE)模型,Y-迷宫对两组大鼠进行行为学检测,免疫组织化学方法观察两组大鼠海马CA3区NR2B表达的变化,反转录多聚酶链反应(RT-PCR)方法检测大鼠海马NR2B mRNA的表达。结果癫癎组大鼠空间学习记忆能力受损;其海马CA3区NR2B阳性细胞较对照组明显减少(P<0.01),同时伴有海马NR2B mRNA表达下降(P<0.01)。结论戊四氮点燃癫癎大鼠空间学习记忆受损可能与海马神经元NR2B的表达减少有关。     

丁基苯酞对慢性脑缺血老龄大鼠海马中NMDA受体亚单位NR2B及突触素表达的影响

目的 观察丁基苯酞对慢性脑缺血老龄大鼠海马中N-甲基-D-天门冬氨酸受体2B亚单位(NR2B)及突触素表达的影响.方法 采用免疫组化方法观察丁基苯酞对慢性脑缺血老龄大鼠海马中NR2B及突触素表达的影响.结果 B组与A组比较,海马CA1区、CA3区及齿状回NR2B及突触素的表达明显减少(P＜0.05),C、D组大鼠海马各区NR2B及突触素的表达与单纯缺血组比较均不同程度增加(P＜0.05);D组与C组比较,NR2B及突触素的表达增加更明显(P＜0.05).结论 慢性缺血3个月后,大鼠海马CA1区、CA3区及齿状回中NR2B 及突触素的表达明显减少,而丁基苯酞能改善这种缺血改变,增加NR2B 及突触素的表达.     

脑脉泰对慢性脑缺血大鼠认知功能的保护作用及其机制研究

目的研究脑脉泰影响脑组织神经生长因子(NGF)、胶质纤维酸性蛋白(GFAP)的表达,进而改善慢性脑缺血大鼠的认知功能。方法采用大鼠双侧颈总动脉永久结扎法(2-VO)制备慢性脑缺血模型。术后分别给予脑脉泰不同剂量灌胃治疗6 w。应用Morris水迷宫测定大鼠的学习记忆能力、HE染色观察海马CA1区神经元形态、免疫组化方法检测大鼠脑组织NGF及GFAP的表达。结果与假手术组相比,模型组大鼠的学习能力和记忆能力降低,脑组织中NGF表达减少(P<0.01),GFAP表达增多(P<0.01);脑脉泰给药能够改善大鼠的记忆和学习能力,增加脑组织中NGF表达(与模型组相比,低剂量组P<0.05,高剂量组P<0.01),降低GFAP表达(与模型组相比,低、高剂量均为P<0.01)。结论脑脉泰可能通过提高脑组织NGF和降低GFAP表达来改善慢性脑缺血大鼠的认知功能。     

PKC、CaMK Ⅱ在慢性脑缺血大鼠认知功能损害中的作用

目的 观察慢性脑缺血大鼠海马组织蛋白激酶C(protein kinase C,PKC)、钙调素依赖蛋白激酶Ⅱ(calmodulin-depend-ent protein kinase Ⅱ,CaMK Ⅱ)水平变化,探讨其在慢性脑缺血认知功能损害中的作用.方法 采用双侧颈总动脉永久性结扎(per-manent occlusion of bilateral common carotid arteries,2-VO)制作慢性脑缺血模型,40只大鼠随机分为假手术组,缺血3周组,缺血8周组,缺血12周组(n=10),Morris水迷宫检测大鼠空间学习记忆能力,Western blot法检测大鼠海马神经元PKC、CaMKⅡ、谷氨酸受体NMDAR1、NMDAR2B的表达水平,并观察其动态变化过程.结果缺血3周组大鼠的空间学习记忆能力较假手术组显著下降(P<0.05),缺血8周和12周组下降更加明显(P<0.01).缺血3周组海马区PKC、CaMKⅡ与谷氨酸受体NMDAR 1、NMDAR 2B表达水平较假手术组增高(P<0.01),缺血8周和12周组表达均降低(P<0.01).结论 PKC、CaMKⅡ与谷氨酸受体NMDAR 1、NMDAR2B变化规律相同,在缺血后期PKC、CaMKⅡ表达减低可能与学习记忆损害有关.     

骨髓间充质干细胞移植对慢性脑缺血大鼠认知功能及海马CA1区EphB2的影响

目的 观察骨髓间充质干细胞移植(mesenchymal stem cells,MSCs)对慢性脑缺血大鼠认知功能及海马CA1区EphB2的影响.方法 将SD大鼠随机分为假手术组、模型组、实验组(2VO模型+MSCs干预),选8、10、12w 3个时间点,采用双侧颈总动脉永久性阻断法(2VO)建立慢性脑缺血模型,通过Morris水迷宫检测各组大鼠的认知功能,同时用免疫组织化学的方法和Western blot检测大鼠海马CA1区EphB2的表达.结果 模型组和实验组大鼠与假手术组相比逃避潜伏期明显延长,在同一时间点实验组逃避潜伏期较模型组明显缩短(P＜0.05),实验组海马CA1区EphB2的表达较模型组增多(P＜0.05).结论 骨髓间充质干细胞移植能明显改善大鼠慢性脑缺血所致的认知功能障碍,其机制可能是通过升高EphB2的表达而改善学习记忆能力.     

血管性痴呆大鼠N-甲基-D-天冬氨酸-2B受体变化机制的研究

目的 研究血管性痴呆（VD）大鼠形成过程中N-甲基D-天冬氨酸-2B受体（NR2B）的变化规律及作用机制.方法 永久性结扎双侧颈总动脉制备VD大鼠模型,用Morris水迷宫衡量大鼠的学习记忆水平,用免疫组化法检测大鼠海马NR2B的表达.结果 随缺血时间延长,VD大鼠的学习记忆能力下降,缺血4周后与对照有显著差异（P＜0.01）;NR2B的表达随缺血时间变化,呈先升后降改变,缺血2周时表达最多,与对照有显著差异（P＜0.01）,此后逐渐减少,并明显低于对照组（P＜0.01）,缺血16周时表达最少.结论 VD大鼠学习记忆的改变与海马NR2B的变化相关,缺血早期NR2B过表达产生神经毒引起该能力下降;而在慢性缺血期,这种损害则是因NR2B含量不足难以完成生理功能所致.     

经鼻给神经生长因子对大鼠脑外伤后β-淀粉样蛋白表达的影响

目的 探讨经鼻给神经生长因子(NGF)对实验性创伤性脑损伤(TBI)大鼠中枢神经系统中β-淀粉样蛋白(Aβ)表达的影响.方法 将80只大鼠采用完全随机分组法分为假手术组(n=26)、对照组(n=27)和治疗组(n=27),参照Feeney自由落体法制作TBI大鼠模型,治疗组经鼻给予NGF治疗.采用平衡木和Morris水迷宫方法评估3组大鼠的神经功能恢复情况.取伤侧海马,通过ELISA方法定量各组大鼠海马部位Aβ的表达;行免疫组织化学染色检测各组大鼠脑组织中淀粉样蛋白前体(APP)的生成情况.结果 治疗组TBI大鼠与对照组相比,平衡木运动协调功能(s)恢复较快(19.00±6.99与27.33±7.39,F2,b=12.87,P=0.028),Morris水迷宫实验显示治疗组潜伏期明显短于对照组;治疗组在原平台象限所占时间百分比(45.82％±11.15％)及穿越平台次数(8.60±2.73)较对照组(33.99％±3.46％、3.60±2.06)均明显增多(F2,15=6.814,P=0.037;F2,15=5.346,P=0.04).ELISA检测显示治疗组Aβ浓度的增高幅度较对照组下降显著.免疫组织化学观察发现APP的阳性细胞数目在3组之间差异有统计学意义(F2,15=8.672,P=O.O03),但对照组和治疗组相比差异无统计学意义.结论 经鼻给NGF可降低TBI大鼠中枢神经系统中Aβ的表达,促进损伤后神经功能的恢复.     

NMDA受体亚单元NR2A和NR2B mRNA在缺血大鼠海马的表达及其与细胞凋亡的关系

目的 探讨短暂性前脑缺血后大鼠海马NR2A和NR2B mRNA的表达变化及其与海马缺血性细胞凋亡的关系。方法 四动脉阻断法建立脑缺血再灌注动物模型、原位杂交、TUNEL染色和图像分析与统计处理。结果 ①缺血后，NR2A和NR2B mRNA在海马各区呈现出一种相对一致的表达规律。在CA1区，NR2A和NR2B mRNA的表达分别在缺血再灌6h和12h降至低谷，然后回升，在缺血再灌48h都升至高峰，之后表达再次下降，直至缺血后7d；在CA3区，该变化规律依然存在，不同的是表达变化的幅度明显减小；而在齿状回，缺血再灌0．5～72h，二者的表达未见显著性变化；72h后，表达下降，直至缺血后7d。②缺血后24h，凋亡细胞出现，主要位于海马CA1区，进行性增多，48h增加更为明显，缺血后72h达高峰；然后凋亡细胞有所减少，但至缺血后7d，依然存在。结论 短暂性前脑缺血后，大鼠海马各区NR2A和NR2B mRNA的表达变化及细胞凋亡均存在着显著性差异；这种差异提示，缺血后，NR2A和NR2B mRNA的表达变化与海马的选择性易损现象和缺血性细胞凋亡之间可能存在着某种密切的关系。     

Angelica injection reduces cognitive impairment during chronic cerebral hypoperfusion through brain-derived neurotrophic factor and nerve growth factor

The current study investigated whether chronic cerebral hypoperfusion produced by permanent bilateral common carotid artery occlusion (2-vessel occlusion (2-VO)) induced cognitive impairment and whether angelica injections alleviated the impairment. Furthermore, the study examined whether 2-VO altered the expression patterns of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in the hippocampus of rats and whether angelica injections attenuated the alteration. Rats were divided into four groups to receive either 2-VO surgery or sham surgery followed by either angelica injections or saline injections for eight weeks. Spatial learning in Morris water maze and the expression patterns of BDNF and NGF in the hippocampus of all rats were examined. The results showed that 2-VO significantly impaired spatial learning and memory, and angelica injections significantly reversed the learning and memory impairment. Furthermore, 2-VO resulted in significantly decreased BDNF protein, NGF protein, and NGF mRNA expression in the hippocampus. Angelica injections significantly attenuated the decreased expression. Moreover, spatial learning in Morris water maze was positively correlated to the expression of BDNF and NGF in the hippocampus. Thus, angelica injections might alleviate cognitive impairment during chronic cerebral hypoperfusion through BDNF and NGF.     

慢性脑低灌注大鼠海马缝隙连接蛋白32和36的表达变化

目的：观察慢性脑低灌注大鼠海马组织中缝隙连接蛋白（Cx）32和Cx36的变化,探讨其在慢性脑低灌注认知功能损害中的作用。方法：双侧颈总动脉永久性结扎（2VO）制作慢性脑低灌注模型,Morris水迷宫检测2VO大鼠空间学习记忆能力变化,免疫组化检测2VO大鼠海马各区Cx32和Cx36的表达水平。结果：慢性脑低灌注大鼠的空间学习记忆能力较假手术对照组显著下降,海马Cx32和Cx36的表达也有降低。结论：Cx32和Cx36可能参与了慢性脑低灌注导致的认知功能损害。     

PKA-CREB信号转导通路在大鼠慢性脑缺血所致认知功能障碍中的作用

目的:观察PKA-CREB信号转导通路在慢性脑缺血所致大鼠认知功能损害中的作用。方法:结扎大鼠双侧颈总动脉,制成慢性脑缺血模型,分缺血8周组和假手术对照组,术后第8周时用Morris水迷宫测定大鼠学习记忆能力。用Westernbloting检测大鼠海马胞核内PKAca及pCREB的表达。结果:缺血组与假手术组相比学习记忆能力明显下降(P<0.05),缺血组大鼠海马中PKAca及pCREB的表达与假手术组相比也下降(P<0.05),且两者之间的下降存在正相关关系。结论:PKA-CREB信号转导通路可能参与了慢性脑缺血所致大鼠认知功能的损害。     

慢性脑缺血老龄大鼠海马区突触素及NMDAR2B表达的研究

目的 本实验旨在观察慢性脑缺血老龄大鼠海马区突触素及NR2B表达的变化.方法 健康Wistar大鼠100只,随机分为5组,A组(对照组)、B组(缺血4周组)、C组(缺血8周组)、D组(缺血12周组)、E组(缺血16周组),每组20只.造模方法采用手术结扎大鼠双侧颈总动脉.分别于手术后4周、8周、12周、16周,采用免疫...     

Long-term effects of seizures in neonatal rats on spatial learning ability and N-methyl-D-aspartate receptor expression in the brain

For the purpose of investigating the long-term effects of seizures in neonatal rats on spatial learning ability and N-methyl-D-aspartate (NMDA) receptor expression in adult rat brain, a seizure was induced by inhalant flurothyl daily in neonatal Wistar rats from postnatal day 6 (P6). The authors assigned six rats each averagely into the single-seizure group, the recurrent-seizure group (seizures induced in six consecutive days), and the control group. During P60 to P65, the rats were tested for spatial learning ability with the Morris water maze task. On P75, the authors examined protein expression of the NMDA receptor (NR) subunits, NR1, 2A, 2B, 2C, and 2D, in the cerebral cortex and hippocampus by Western blotting analysis. On P65, the escape latencies from the water maze of the rats in the recurrent-seizure group were significantly longer than those of the control rats, but there was no difference between the single-seizure group and the control group. NR subunit expression in the cerebral cortex and hippocampus of the rats with single seizure was similar to those in the control rats. Compared with the control rats, the protein expressions of NR1, NR2A and NR2B in the cerebral cortex and NR2A in the hippocampus of the recurrent-seizure group was significantly decreased, but NR2C protein expression in the cerebral cortex and hippocampus significantly increased. Recurrent seizures induced in neonatal rats might cause long-term spatial learning ability deficit and modify NR expression in the cerebral cortex and hippocampus of adult rats. The results suggest that abnormal NR expression might play an important role in long-term spatial learning ability deficit induced by recurrent seizures in early life.     

慢性脑低灌注对2型糖尿病模型大鼠空间学习记忆能力的影响及胆碱能神经元损伤的机制探讨

目的探讨2型糖尿病（DM）是否加重慢性脑低灌注（CCH）大鼠胆碱能神经元及空间学习记忆能力损伤。方法SD大鼠24只,随机分为4组（均n=6）：①对照组（正常饮食＋假手术）;②DM组[高脂饮食＋链脲佐菌素（STZ）];③CCH组[正常饮食＋双侧颈总动脉永久性结扎（2-VO）];④DM-CCH组（高脂饮食＋STZ＋2-VO）。采用Morris水迷宫测试各组大鼠学习记忆能力;免疫组化学法检测海马区乙酰胆碱转移酶（CHAT）阳性细胞表达和免疫印迹法检测海马ChAT相对表达量。结果DM＋CCH组逃避潜伏期与对照组比较明显延长,第2-4天（P〈0．001）、第5天（P〈0．01）;目标象限时『目】百分比明显低干对照组（P〈0．01）、DM组（P〈0．05）和CCH组（尸〈O．05）。DM＋CCH组海马区ChAT阳性细胞表达明显减少,ChAT相对表达量较对照组显著减少（P〈0．01）、DM组（P〈0．05）和CCH组（P〈0．05）显著减少。结论DM可加重CCH大鼠的空间学习记忆能力障碍,可能与海马区胆碱能神经元损伤有关。     

A lasting effect of postnatal sevoflurane anesthesia on the composition of NMDA receptor subunits in rat prefrontal cortex

Sevoflurane is widely used in pediatric anesthesia and studies have shown that it is capable of inducing neurodegeneration and subsequent cognitive disorders in the developing brain. However, the evidence that anesthetics are toxic to the human brain is insufficient. N-Methyl-d-aspartate (NMDA) receptors, critical for learning and memory, display expression changes with age and can be modulated by inhalation anesthetics. Generally, NMDA receptor (NR) type 1 is expressed at birth, peaks around the third postnatal week, and then declines slightly to adult levels. NR2Bs slowly decrease and NR2As gradually increase during postnatal development. These developmental switches of NMDA receptor subunits composition mark the transition from immature to adult neural processing and allow for the final maturation of associative learning abilities. In this study, we aimed to evaluate the effect of repeated sevoflurane anesthesia on NMDA receptor subunits composition in the developing rat brain and related behavioral disorders. Six-day-old male Sprague Dawley rats were randomly allocated into either a control group (group con) or a sevoflurane group (group sevo). Group sevo inhaled 2.1% sevoflurane carried by 70% oxygen for 2 h each day from postnatal day (PND) 6 to PND 8. The same procedure, without applying the sevoflurane, was executed in group con. The membrane protein expression of NR1, NR2A and NR2B in the prefrontal cortex (PFC) and hippocampus was assessed at the end of the three days of anesthesia and at PND 21. An open field test was carried out to assess spontaneous locomotion on PNDs 21, 28 and 35. Y maze performance was used to assess attention and working memory on PND 28. Sevoflurane induced upregulation of NR1 and NR2B in the PFC at the end of anesthesia. On PND 21, NR1 and NR2B receptors were significantly increased whereas NR2A receptors were significantly decreased in the PFC in group sevo. Sevoflurane-treated rats showed hyper-locomotion and impairment of working memory in the behavior tests. These results indicate that repeated sevoflurane anesthesia at early stage of life can induce a long lasting effect of interfering with NMDA receptor subunits composition in rat PFC. These changes may contribute to the effects of sevoflurane on neuronal development and subsequent neurobehavioral disorders.     

慢性脑低灌注大鼠海马Arc低表达与其认知功能障碍的相关性研究

目的 探讨慢性脑低灌注大鼠海马活性调节的细胞骨架相关蛋白(activity-regulated cytoskeletal-associated protein,Arc)的低表达与其认知功能障碍的相关性。方法 大鼠慢性脑低灌注模型使用持久性双颈总动脉结扎术(2-vessel occlusion,2-VO); 大鼠随机分成假手术组和2-VO组,每组各6只。术后第8周行Morris水迷宫评价其认知功能; 实时定量聚合酶链式反应(Real time quantitative polymerase chain reaction,RT-qPCR)及蛋白免疫印迹法检测大鼠海马Arc mRNA及蛋白表达水平。结果(1)2-VO组大鼠第2～5 d的逃逸潜伏期比假手术组明显延长(P<0.01)及其在原平台区域游泳时间明显比假手术组短(P<0.01);(2)2-VO组大鼠海马Arc mRNA水平及免疫反应条带相对灰度值分别比假手术组明显降低(P均<0.01);(3)空间探索实验中2-VO大鼠在原平台区域游泳时间与海马Arc免疫反应条带相对灰度值呈正相关(r=0.7085,P<0.05)。结论 慢性脑低灌注大鼠的认知功能障碍可能与海马Arc的低表达相关。