血管性痴呆小鼠海马胆碱乙酰转移酶mRNA表达特征研究

目的探讨血管性痴呆小鼠海马神经元胆碱乙酰转移酶原位杂交变化特征及其在血管性痴呆发病中的作用。方法双侧颈总动脉线结反复缺血-再灌注法制备模型,利用跳台试验和水迷宫试验观测其行为学改变,采用原位杂交技术观测小鼠海马神经元胆碱乙酰转移酶mRNA的表达变化。结果模型组小鼠学习、记忆成绩较假手术明显降低(P<0.01),其海马胆碱乙酰转移酶mRNA表达也明显下降(P<0.01)。结论血管性痴呆小鼠学习、记忆成绩下降可能与其海马胆碱乙酰转移酶mRNA低水平表达有关。     

血管性痴呆小鼠海马胆碱乙酰转移酶mRNA表达特征及石杉碱甲的影响

目的观测石杉碱甲对血管性痴呆小鼠海马神经元胆碱乙酰转移酶(ChAT)原位杂交的影响,进一步研究其在血管性痴呆发病中的作用及石杉碱甲对其影响的机制。方法双侧颈总动脉线结,反复缺血-再灌注法制备模型,药物组用石杉碱甲溶液灌胃,跳台试验和水迷宫试验观测其行为学改变,采用原位杂交技术观测小鼠海马神经元ChAT mRNA的表达变化。结果石杉碱甲组小鼠学习、记忆成绩优于模型组(P<0.01),其海马ChATmRNA表达也明显增高(P<0.01)。结论石杉碱甲改善血管性痴呆小鼠学习、记忆成绩与其恢复海马低水平的ChAT mRNA有关。     

β—淀粉样蛋白对大鼠学习记忆功能及脑胆碱乙酰转移酶和生长抑素表达的影响

目的：探讨Meynert核注射β-淀粉样肽（Aβ）大鼠学习记忆功能ChAT,SOM神经元的影响。方法：将1μLAβ1-40（10μg/μL）在立体定位仪下注入大鼠右侧Meynert核，分别于1周，4周时测定其学习记忆能力和脑组织中ChAT及SOM免疫反应阳性神经元的表达。结果：Aβ注射1周后，实验组出现学习记忆障碍，呈渐进性加重，4周时更为显著，在无名质区Meynert核及其边周，海马区和额，顶部皮质区，正常对照组和假手术组均有广泛的ChAT及SOM免疫反应阳性神经元分布，而实验组则减少，在4周时，实验组ChAT及SOM免疫反应阳性神经元表达显著减少，以Meynert核及其边周最显著。结论：Meynert核注射Aβ可使大鼠发生较持久的学习记忆功能障碍，Aβ致Meynert核、海马和皮质区的ChAT及SOM能神经元的减少，可能是学习记忆功能障碍和痴呆形成的重要因素之一。     

血管性痴呆小鼠海马胆碱乙酰转移酶mRNA变化特征及喜得镇的影响

目的:观测喜得镇对血管性痴呆小鼠海马神经元胆碱乙酰转移酶mRNA变化的影响,以探讨胆碱乙酰转移酶mRNA变化在血管性痴呆发病中的作用及喜得镇对此变化的机制。方法:双侧颈总动脉线结.反复缺血-再灌注法制备模型,药物组用喜得镇溶液灌胃,利用跳台试验和水迷宫试验观测其行为学改变,采用原位杂交技术观测小鼠海马神经元胆碱乙酰转移酶mRNA的表达变化。结果:喜得镇组小鼠学习、记忆成绩优于模型组(P<0.01),其海马胆碱乙酰转移酶mRNA表达也明显增高(P<0.01)。结论:喜得镇改善血管性痴呆小鼠学习、记忆成绩与其恢复海马低水平的胆碱乙酰转移酶mRNA有关。     

无名质区破坏的Wistar大鼠脑内胆碱乙酰转移酶和生长抑素…

本研究选用Ｗｉｓｔａｒ系雄性大鼠，通过向鼠脑的无名质区注射Ｉｂｏｔｅｎｉｃａｃｉｄ，造成中枢胆碱能系统破坏的动物模型，采用放免方法，测定了无名质区破坏后大鼠不同脑区ＣｈＡＴ活性和ＳＳ含量的变化，结果发现：大鼠一侧无名质区破坏后，同侧大脑皮质额叶，顶叶的ＣｈＡＴ活性显著下降，同时同侧额叶，顶叶及海马的ＳＳ含蛳也明显降低。结果显示，中枢胆碱能系统和生长抑素系统有极密切的关系，无名质区破坏后脑内ＳＳ含量     

天智颗粒对血管性痴呆大鼠行为学及脑内AchE、ChAT活性的影响

目的观察天智颗粒对血管性痴呆大鼠行为学习记忆能力和乙酰胆碱代谢酶活性的影响,从而探讨天智颗粒改善记忆的机制.方法采用双侧颈总动脉结扎法建立血管性痴呆模型,治疗组用天智颗粒(5 g/kg)灌胃,模型组和假手术组用同体积的蒸馏水代替灌胃,1次/天,对照组未做任何处理.30 d后,采用三等分Y型电迷宫和比色法分别测定皮质、海马区乙酰胆碱脂酶(AchE)活性和基底前脑区胆碱乙酰转移酶(ChaT)活性.观察、比较各组大鼠行为学和乙酰胆碱代谢酶的变化规律和差异.结果治疗30d后,治疗组与模型组相比,学习记忆能力和基底前脑ChaT活性明显提高(P＜0.05),但皮质和海马区AchE活性变化无统计学意义.结论天智颗粒能明显促进血管性痴呆大鼠学习记忆能力和基底前脑区ChaT活性,其药理机制可能和改变乙酰胆碱代谢酶活性有关.     

无名质区破坏的Wistar大鼠脑内胆碱乙酰转移酶和生长抑素活性的变化及相互关系

本研究选用Ｗｉｓｔａｒ系雄性大鼠，通过向鼠脑的无名质区注射Ｉｂｏｔｅｎｉｃａｃｉｄ，造成中枢胆碱能系统破坏的动物模型。采用放免方法，测定了无名质区破坏后大鼠不同脑区ＣｈＡＴ活性和ＳＳ含量的变化。结果发现：大鼠一侧无名质区破坏后，同侧大脑皮质额叶，顶叶的ＣｈＡＴ活性显著下降，同时同侧额叶、顶叶及海马的ＳＳ含量也明显降低。结果提示：中枢胆碱能系统和生长抑素系统有极密切的关系，无名质区破坏后脑内ＳＳ含量的下降，可能是伴随着胆碱能系统损伤的继发性改变。推测ＳＳ系统可能接受胆碱能系统的传入，参与对学习、记忆的调节。     

雌激素对血管性痴呆大鼠认知功能及海马CA1区胰岛素样生长因子-1、胆碱乙酰转移酶表达的影响

目的 探讨雌激素对血管性痴呆(VD)大鼠认知功能及海马CA1区胰岛素样生长因子-1(IGF-1)、胆碱乙酰转移酶(ChAT)表达的影响.方法 30只雄性SD大鼠随机分为假手术组、VD组和雌激素组,每组10只.采用双侧颈总动脉结扎(2VO)法制备VD大鼠模型;雌激素组大鼠腹腔注射17-β雌二醇(花生油溶解)1 mg/kg,假手术组和VD组大鼠腹腔注射等量的花生油,均为隔日1次,共30次.60 d后,用Morris水迷宫检测各组大鼠逃避潜伏期和跨越平台次数;HE染色观察大脑海马CA1区神经细胞形态学变化,免疫组化染色检测海马CA1区IGF-1、ChAT阳性细胞数.结果 假手术组海马CA1区未见明显的病理变化;VD组神经细胞数量和层次明显减少;雌激素组偶见小的软化灶,细胞数和形态接近假手术组.与假手术组相比,VD组及雌激素组逃避潜伏期明显延长,跨越平台次数明显减少,海马CA1区IGF-1表达明显增加,ChAT表达明显减少(均P<0.05);与VD组比较,雌激素组逃避潜伏期明显缩短,跨越平台次数明显增加,海马CA1区IGF-1及ChAT表达明显增加(均P<0.05).结论 雌激素可以通过上调内源性IGF-1而减轻海马神经元损伤,增加ChAT的表达,改善VD大鼠认知功能.     

苯甲酸雌二醇对慢性脑缺血大鼠海马胆碱乙酰转移酶变化及雌激素的影响

目的观察苯甲酸雌二醇对慢性脑缺血大鼠海马神经元胆碱乙酰转移酶的影响,以探讨胆碱乙酰转移酶的变化在慢性脑缺血发病中的作用及雌二醇对此变化的影响。方法采用双侧颈总动脉永久性结扎制备慢性脑缺血模型,30只大鼠随机分为假手术组、缺血组和雌二醇治疗组。各组于造模60d后,应用Y迷宫观察其行为学改变,采用免疫组化观测大鼠海马神经元胆碱乙酰转移酶的变化。结果治疗组较缺血组认知障碍明显改善（P〈0.01）,其海马胆碱乙酰转移酶的表达也明显增高（P〈0.01）。结论苯甲酸雌二醇能改善慢性脑缺血大鼠的认知功能可能与其提高海马区胆碱乙酰转移酶水平有关。     

β-淀粉样蛋白对大鼠学习记忆功能及脑胆碱乙酰转移酶和生长抑素表达的影响

目的:探讨Meynert核注射β-淀粉样肽(Aβ)对大鼠学习记忆功能和ChAT,SOM神经元的影响.方法:将1μLAβ1～40(10μg/μL)在立体定位仪下注入大鼠右侧Meynert核,分别于1周、4周时测定其学习记忆能力和脑组织中ChAT及SOM免疫反应阳性神经元的表达.结果:Aβ注射1周后,实验组出现学习记忆障碍,呈渐进性加重,4周时更为显著.在无名质区Meynert核及其边周、海马区和额、顶部皮质区,正常对照组和假手术组均有广泛的ChAT及SOM免疫反应阳性神经元分布,而实验组则减少.在4周时,实验组ChAT及SOM免疫反应阳性神经元表达显著减少,以Meynert核及其边周最显著.结论:Meynert核注射Aβ可使大鼠发生较持久的学习记忆功能障碍,Aβ致Meynert核、海马和皮质区的ChAT及SOM能神经元的减少,可能是学习记忆功能障碍和痴呆形成的重要因素之一.     

Ameliorating Effects of SDZ ENA 713 on Age-Associated Decreases in Learning Performance and Brain Choline Acetyltransferase Activity in Rats

In the present study, we have investigated the effects of SDZ ENA 713 on spatial learning deficits in aged rats. Using the same animals, the effect of SDZ ENA 713 on choline acetyltransferase was simultaneously studied to obtain a basis for the behavioral study. In the aged rats, the spatial learning and choline acetyltransferase activity in the frontal cortex were significantly deteriorated compared with young adult rats. SDZ ENA 713 (0.2 mg/kg) significantly shortened the time to reach a hidden platform without affecting swim rates in the water maze task. SDZ ENA 713 (0.1 and 0.2 mg/kg) inhibited aging-induced decreases in choline acetyltransferase activity in the frontal cortex. These results suggest that SDZ ENA 713 ameliorates aging-induced learning deficits and cholinergic dysfunction in rats.     

Nerve Growth Factor Receptor-immunoreactive Fibres Innervate the Reticular Thalamic Nucleus: Modulation by Nerve Growth Factor Treatment in Neonate,Adult and Aged Rats

Terminal arborizations expressing nerve growth factor receptor (NGF-R) have been detected with immunohistochemistry in the reticular thalamic nucleus of neonate, adult and aged rats. Intracerebroventricular administration of nerve growth factor (NGF) resulted in a dramatic increase in NGF-R immunoreactivity throughout the lifespan. This effect was paralleled by a concomitant increase in NGF-R immunopositivity in the neurons of the basal forebrain, which was here demonstrated also in aged animals, thus indicating that the NGF-R immunoreactivity within the reticular thalamic nucleus derives in all likelihood from cholinergic neuronal cell bodies of the basal forebrain. Our results demonstrate a prominent ability of NGF to up-regulate its receptors within fibres innervating the reticular thalamic nucleus, and show that this up-regulation of NGF-R is maintained throughout the lifetime. Altogether this indicates that the reticular thalamic nucleus may represent a new, important site of action of endogenous NGF or NGF-like molecules within the brain. In view of the crucial role played by the reticular thalamic nucleus in gating thalamocortical information, the autoregulation of NGF-R in this structure may have important concomitants in both physiological and pathological conditions.     

阿尔茨海默病大鼠海马额叶Bcl-2蛋白表达的改变

目的研究珂尔茨海默病(AD)大鼠学习记忆及Bcl-2蛋白表达的改变。方法β淀粉样蛋白(βAP)注入大鼠迈内特基底核(NBM)建立AD型．Y迷宫测定学习记忆能力,流式细胞仪检测Bcl-2蛋白含量。治疗组腹腔注射尼莫的平2周。结果模型组大鼠学习记忆能力下降,海马和额叶Bcl-2蛋白含量增高;治疗组Bcl-2水平下调,学习记忆有所改善,但与对照组比仍有差异。结论βAP注入NBM引起大鼠学习记忆损害,Bcl-2蛋白的表达增加。     

一种帕金森病大鼠模型的建立及评价

目的探讨应用6-羟基多巴胺（6-OHDA）毁损大鼠黑质致密部制作偏侧帕金森病（PD）模型的方法和应用价值。方法采用立体定向微量注射6-OHDA于大鼠黑质致密部,观察经阿朴吗啡诱导后大鼠的行为及黑质多巴胺能神经元形态学变化。结果部分大鼠注射后即出现行动迟缓、少动、竖毛、躬身、尾部强直、肢体震颤、嗅探和易激惹等异常行为。术后4周时,共33只大鼠经阿朴吗啡诱导后在30min（P〈0．01）的平均旋转圈数〉7r／min,达到成功模型的标准,模型成功率为82．5％（33／40）。免疫组化观察发现模型组大鼠注射侧黑质区多巴胺能神经元较对侧和对照组注射侧区明显减少（P〈0．01）。结论利用6-OHDA毁损大鼠黑质致密部可以较快建立稳定的PD大鼠模型,方法简便实用,动物死亡率低,模型成功率高。     

Morphological Changes of Microvessels in the Brain with Alzheimer's Disease

Abstract: The pathological changes of microvessels in the cerebral cortex in Alzheimer's disease were examined at the ultrastructural level.
With transmission electron microscopy (TEM), the endothelial cells of many capillaries their pericytes exhibited atrophy swelling with a narrowed lumen. The capillary basal laminas were thickened tortuous. After isolation of the microvessels by ultrasonic treatment collagenase digestion, the vascular wall structure was viewed by scanning electron microscopy (SEM). Most of the terminal arterioles had smooth muscle cells with an irregular shape arrangement often showed a series of focal constrictions. In some areas, the capillaries were arrayed in a bundle terminated with tapered ends. Associated with the microvessels were fine filaments which may represent amyloid fibrils.
The findings indicate that diffuse atrophy the deletion of nerve cells in the cerebral cortex might be caused, at least partly, by a circulatory disturbance through the patho-morphologically changed microvessels.     

Neurodegeneration and cognitive impairment in apoE-deficient mice is ameliorated by infusion of recombinant apoE

Recent studies suggest that apolipoprotein E (apoE) might play a neurotrophic function in the central nervous system and that altered functioning of this molecule could result in neurodegeneration. The main objective of this study was to determine if neurodegenerative and cognitive alterations in apoE-deficient mice are reversible by infusion of recombinant apoE into the lateral ventricles. ApoE-deficient mice treated with either apoE3 or apoE4 showed a significant improvement in their learning capacity in the Morris water maze compared to saline-infused apoE-deficient mice. While this improved performance was associated with restoration of neuronal structure, the poor learning ability of apoE-deficient mice treated with saline correlated with the disrupted synapto-dendritic structure. This study supports the contention that apoE might play a neurotrophic effect in vivo and suggests that apoE might have a potential therapeutic role. © 1997 Elsevier Science B.V. All rights reserved.     

ELISA methods to measure cholinergic markers and nerve growth factor receptors in cortex, hippocampus, prefrontal cortex, and basal forebrain from rat brain

The central cholinergic system has a fundamental role in normal cognitive function, and in diseases that exhibit cognitive dysfunction. The purpose of this study was to design ELISA methods to measure proteins that have essential functions in the central cholinergic system. We were particularly interested in quantifying proteins that respond directly or indirectly to nerve growth factor (NGF). ELISAs offer advantages over Western blot analyses and other methods, such as increased sensitivity, decreased assay variability, increased efficiency, and decreased cost. We developed indirect ELISA methods for: choline acetyltransferase (ChAT); the vesicular acetylcholine transporter (VAChT); the high affinity choline transporter (HACT/CHT); TrkA, the high affinity NGF receptor; the p75 neurotrophin receptor (p75^NTR). A sandwich ELISA was developed to measure tyrosine-phosphorylated TrkA in brain lysates. We used these ELISAs to compare levels of the above proteins in important memory-related brain regions – basal forebrain, hippocampus, cortex, and prefrontal cortex – from old and young rats. We identified age-related differences in the levels of the aforementioned proteins (e.g., VAChT and HACT/CHT in hippocampus). Thus, these ELISA methods should be particularly useful for comparing the effects of age, disease, drugs, and toxicants on brain levels of key cholinergic and growth factor-related proteins.     

小檗碱对阿尔茨海默病大鼠模型胰岛素降解酶表达的影响

目的 研究小檗碱对AD大鼠模型胰岛素降解酶(IDE)表达的影响.方法 18只SD大鼠采用完全随机数字表法分为正常组、模型组和小檗碱组,每组6只.正常组不做任何处理,模型组及小檗碱组大鼠通过双侧海马立体定向注射凝聚态Aβ1-40(5 μg)建立AD模型.小檗碱组造模后灌胃给予盐酸小檗碱50mg/kg,1次/d,共14d.采用实时荧光定量PCR法和Western blotting法观察小檗碱对IDE表达的影响.结果 小檗碱组大鼠IDE mRNA的相对拷贝数(45.70±12.80)较正常组(23.40±11.30)及模型组(34.20±6.70)明显增加,小檗碱组大鼠海马IDE蛋白相对表达量(0.61±0.05)较正常组(0.23±0.03)及模型组(0.46±0.07)明显增加,差异均有统计学意义(P＜0.05).结论 大鼠海马立体定向注射凝聚态Aβ1-40可以导致海马部位IDE表达增加,小檗碱可以通过促进IDE的表达而促进Aβ的清除.     

Longitudinal CSF isoprostane and MRI atrophy in the progression to AD

Very little data exist to evaluate the value of longitudinal CSF biological markers for Alzheimer's disease (AD).Most studies indicate that tau and amyloid beta markers do not reflect disease progression. We now report on a longitudinal, three-time point, CSF Isoprostane (IsoP) and quantitative MRI study that examined 11 normal elderly (NL) volunteers and 6 Mild Cognitive Impairment (MCI) patients. After 4 years, all 6 MCI patients declined to AD and 2 of the NL subjects declined to MCI. At baseline and longitudinally, the MCI patients showed reduced delayed memory, increased IsoP levels, and reduced medial temporal lobe gray matter concentrations as compared to NL. A group comprised of all decliners to AD or to MCI (n = 8) was distinguished at baseline from the stable NL controls (n = 9) by IsoP with 100% accuracy.Moreover, both at baseline and longitudinally, the IsoP measures significantly improved the diagnostic and predictive outcomes of conventional memory testing and quantitative MRI measurements. These data indicate that IsoP is potentially useful for both the early detection of AD-related pathology and for monitoring the course of AD.     

Regional Distribution of Choline Acetyltransferase and Acetylcholinesterase Activity in Baboon Brain

(1) The activities of choline acetyltrans-ferase (ChAc) (EC 2.3.1.6) and acetyl-cholinesterase (AChE) (EC 3.1.1.7) were determined in about one hundred regions and subregions of baboon brain. The activities and distributions of these enzymes were in comparable to those found previously in the brains of other species. (2) ChAc activity was highest in the in-terpeduncular nucleus, where it was about twice that in the putamen, the region previously thought to be the richest in this enzyme. The caudate nucleus, the substantia perforata, the nucleus basalis, the central part of the amygdala and the oculomotor nucleus also had high activities. The activities in the cerebral and cerebellar cortex were less than one twentieth of that in the inter-peduncular nucleus. (3) The distribution of AChE activity was not entirely in parallel with that of ChAc.