海马注射β-淀粉样蛋白建立阿尔茨海默病大鼠模型的实验研究

目的：海马注射β-淀粉样蛋白（Aβ）建立阿尔茨海默病（AD）大鼠模型，并进行初步评价。方法：应用凝聚态Aβ1-40进行大鼠右侧海马齿状回（DG）背侧细胞带微量注射，2周后从学州记忆、海马组织病理和异常磷酸化tau蛋白表达的变化3个方面评价大鼠模型。结果：Aβ1-40注射后大鼠Morris水迷宫学习记忆能力明显受损（P〈0．01）；注射区内DG背侧细胞带神经元丢失（P〈0．01）；注射侧海乌内Aβ沉积；海马神经元内异常磷酸化tau蛋白的表达显著增加（P〈0．01）。结论：凝聚态Aβ1-40海马注射具有明确的在体神经毒性作用，可导致大鼠认知功能下降以及海马内Aβ沉积、神经元丢失和神经元内异常磷酸化tau蛋白的表达，可成功建立AD大鼠模型。     

脑缺血对阿尔茨海默病大鼠认知功能的影响及炎性机制探讨

目的：探讨脑缺血对阿尔茨海默病（AD）大鼠认知功能的影响及可能机制。方法：大鼠海马注射Aβ1-40成功建立AD大鼠模型后，于AD大鼠右侧纹状体注射内皮素-1建立脑缺血模型，Morris水迷宫检测脑缺血后AD大鼠认知功能的变化，免疫组化、原位杂交和RT-PCR检测海马内星形胶质细胞和IL-1、TNF—α的变化。结果；脑缺血后AD大鼠认知功能明显下降（P〈0．01），海马内星形胶质细胞和炎性细胞因子IL-1、TNF—α的表达都较单纯AD显著增加（P〈0．01）。结论：脑缺血加重了AD大鼠的认知功能障碍，炎性机制参与了脑缺血促进AD进展的过程。     

褪黑素对Alzheimer病模型大鼠认知功能和海马tau蛋白过度磷酸化的影响

目的 研究褪黑素(MT)对Alzheimer病(AD)模型大鼠认知功能和海马tau蛋白过度磷酸化的影响.方法 给大鼠海马内注射凝聚态β-淀粉样蛋白(Aβ)25-35制作AD模型;MT组大鼠从制模前7 d至制模后19 d每日腹腔注射MT,AD组大鼠制模后腹腔注射生理盐水;用Morris水迷宫试验检测大鼠的认知功能,银染法观察海马神经元形态,免疫组化法观察过度磷酸化tau蛋白的表达,并与正常对照组比较.结果 MT组大鼠Morris水迷宫试验结果明显好于AD组(均P＜0.001);海马CA1区磷酸化tau蛋白阳性细胞数(60.0±2.3)明显少于AD组(98.4±3.0)(P＜0.001),与正常对照组比较差异无统计学意义;海马CA1区神经元纤维形态较AD组规则.结论 MT可明显改善AD大鼠的认知功能,并且抑制海马tau蛋白的过度磷酸化.     

炎性细胞因子在早期母子分离对成年后 大鼠认知功能影响中的作用

目的 研究早期母子分离对成年雄性大鼠认知功能的影响,以及海马区炎性细胞因子在 其中的作用,以探讨生命早期应激对神经发育影响的机制。方法 新生SD大鼠随机分成母子分离组（MS 组）和空白对照组（NMS 组）,MS 组幼鼠在出生后第3～22 天,每天与母鼠分离3 h。NMS 组不做处理。 10 周龄时,对两组成年大鼠进行Morris水迷宫行为学测试,NeuN免疫荧光染色观察两组大鼠海马齿状 回（DG 区）正常及变性神经元,GFAP/Iba-1 免疫荧光染色观察星形胶质细胞和小胶质细胞,Ki67/DCX 免 疫荧光染色观察神经元增殖、分化情况,蛋白电泳法检测两组大鼠大脑海马区IL-1β、IL-6、TNF-α含 量。结果 相对于NMS 组,行为学测试提示MS 组大鼠学习、记忆能力下降,表现为MS 组大鼠有更长的 逃逸潜伏期,更少的目标象限停留时间和穿越平台次数（P＜ 0.05）;海马DG 区正常及变性神经元的数目 无明显变化（P ＞ 0.05）,但星形胶质细胞及小胶质细胞的数目增加（P ＜ 0.01）,且神经元增殖减少、分化 减缓（P＜ 0.01）;海马区IL-1β、TNF-α表达增高（P＜ 0.01）,IL-6 表达无明显变化（P＞ 0.05）。结论 生 命早期重复母子分离能够引起大鼠海马区神经炎性反应,增加星形胶质细胞和小胶质细胞数目,增高 海马区炎性细胞因子的表达,导致成年后大鼠认知功能的改变。     

局灶性脑缺血/再灌注大鼠白细胞介素-1β蛋白和mRNA的表达

目的 :观察脑缺血对白细胞介素 - 1β(IL- 1β)表达的影响 ,及脑缺血后 IL- 1β的细胞来源。方法 :采用线栓法制备大鼠局灶性大脑中动脉栓塞 (MCAO)模型 ,应用原位杂交观察脑缺血再灌注对 IL- 1β m RNA表达的影响 ;应用荧光双标检测 IL- 1β的表达细胞。结果 :(1)正常和假手术大鼠大脑皮层 IL- 1β m RNA阳性细胞表达较少 ,缺血再灌注后缺血侧皮层 IL- 1β m RNA阳性细胞表达明显增加 ,再灌注后 2 h IL- 1β m RNA表达显著增加 ,再灌注后 2 4h逐渐降至正常水平。 (2 )缺血后表达 IL- 1β m RNA的主要细胞为神经元、星形胶质细胞和小胶质细胞。缺血再灌注后12 h IL- 1β蛋白主要表达于星形胶质细胞和小胶质细胞 ,神经元未见 IL- 1β的表达。结论 :脑缺血后 IL- 1β m RNA表达增加 ,IL- 1β可能在缺血性脑损伤中起重要作用。缺血再灌注后 IL- 1β主要来源于星形胶质细胞和小胶质细胞     

海马注射β-淀粉样蛋白对白介素-1β和肿瘤坏死因子-α表达的影响及消炎痛的干预作用

目的　在体条件下观察 β-淀粉样蛋白 ( Aβ)对白细胞介素 -1 β( IL-1 β)和肿瘤坏死因子 -α( TNF-α)表达的影响 ,探讨它们在 Alzheimer病 ( AD)发病机制中的作用。方法　以不同浓度 Aβ溶液及生理盐水作海马立体定向注射后 ,采用免疫组织化学、HE染色及刚果红染色方法 ,显示胶质细胞反应及 IL-1β、TNF-α表达情况 ;消炎痛灌胃治疗模型大鼠并以蒸馏水作治疗对照。采用方差分析对量化指标行统计学处理。结果　胶质细胞反应程度及 IL-1 β、TNF-α的表达水平随 Aβ浓度增大而增加 ,4 μg/ μL Aβ溶液注射组 IL-1 β、TNF-α阳性细胞数 (个 /视野 )分别为 4 1 .75± 2 .6 1和 5 2 .1 7± 5 .2 3,显著多于生理盐水注射组 ( 2 1 .1 6± 2 .92和 31 .0 7± 3.5 8,P<0 .0 1 ) ;消炎痛显著降低 IL-1 β、TNF-α的表达水平。结论　在体条件下高浓度 Aβ能诱导胶质细胞 IL-1 β和 TNF-α的表达 ,并可被消炎痛抑制 ,结果提示炎症反应与 AD的发病机制可能有密切关系。     

Alzheimer病患者脑tau、β-tubulin的表达

目的 观察Alzheimer病（AD）患者脑tau、β-tubulin的表达、分布与神经元骨架改变的关系。方法 采用免疫组织化学方法观察tau、β-tubulin,在8例AD、5例非痴呆老人（ND）脑海马、嗅球、脑室周围皮质等部位的表达并进行半定量分析。结果 （1）AD组tau蛋白与ND组相比表达明显增加（P＜0．001）,主要在额叶、颞叶、海马、脑室周及嗅球的表达增高（P＜0．05）;顶叶、枕叶无明显差异。大脑新皮层、海马神经元树突、胞膜均有表达,细胞核膜部分着色,部分神经元呈典型NET样结构;星形胶质细胞也有表达。此外,神经毡细丝、老年斑亦有广泛表达。ND组tau散在表达,无NFT样神经元。（2）AD组的β-tubulin明显减少（P＜0．001）,额叶、颞叶、顶叶、海马及脑室周表达明显下降（P＜0．05）;而枕叶与嗅球无差异。β-tubulin在ND组,主要是海马及皮质神经元树突上广泛表达,白质区轴索结构也有阳性表达。结论 AD患者脑内tau表达增高且存在区域分布差异;而tau的过度产生与β-tubulin的表达减少和晚期AD脑内广泛的神经元丢失、结构破坏相一致,提示AD脑内神经原纤维缠结形成与二者改变的机制值得进一步探讨。     

拟阿尔茨海默病模型大鼠海马CA1区HSP27及IL-1表达

目的 探讨Aβ(β-淀粉样肽)诱AD大鼠模型中海马HSP27和IL-1的表达, 研究信号转导及炎性机制在AD中的作用.方法 采用立体定向下双侧海马注射Aβ1-42建立AD动物模型,通过免疫组化染色及Western blot等方法, 观测大鼠学习记忆能力、海马组织结构的病理改变及HSP27和IL-1 的表达情况.结果 HE染色显示,模型组大鼠海马神经元变性、缺失,胶质细胞浸润;免疫组化结果显示模型组大鼠海马CA1区HSP27和IL-1 免疫阳性细胞表达多见(P＜0.05);Western blot显示模型组海马组织HSP条带增宽表达强度高于对照组(P＜0.05).结论 HSP27在AD的炎症反应机制中可能具有重要作用.     

CuSO_4对阿尔茨海默病模型行为学和病理学的影响

目的研究CuSO4对阿尔茨海默病模型大鼠行为学和病理学的影响。方法 SD大鼠经水迷宫淘汰后随机分为6组,正常组、PBS组、AD模型组、低剂量CuSO4组(1 mg/kg)、中剂量CuSO4组(3 mg/kg)、高剂量CuSO4组(5 mg/kg)。处理:PBS组海马CA1区注射无菌PBS溶液;AD模型组为右侧海马注射凝聚态Aβ1⁴2;低中高剂量CuSO4组分别在AD造模成功后取右侧侧脑室注射无菌CuSO4溶液。用Morris水迷宫检测大鼠的行为学变化,冰冻切片HE染色和尼氏染色观察神经元形态学变化情况。Western blot检测总tau蛋白和糖原合成酶激酶3β(GSK-3β)的表达变化。结果与正常组和PBS组相比较,AD模型组大鼠的学习记忆能力下降,神经元凋亡严重,GSK-3β和tau蛋白的表达增加;3组CuSO4处理组与AD组比较,大鼠认知功能下降明显,神经元凋亡严重,GSK-3β和tau表达增加。随着CuSO4注射剂量的增加,大鼠认知功能下降越严重,细胞凋亡越明显,GSK-3β和tau的表达增加。结论 CuSO4侧脑室注射能够损害AD模型大鼠的学习记忆功能,能够促进海马神经元凋亡,能够增加糖原合成酶激酶3β和tau蛋白的表达。     

海马内注射纤丝状Aβ42诱导tau异常磷酸化的研究

目的　观察海马内注射纤丝状Aβ42 后神经元Ser 2 0 2位点磷酸化的tau蛋白 (PS2 0 2 tau)的表达 ,探讨Aβ42 与tau蛋白超磷酸化的关系。方法　应用立体定向技术对老年大鼠进行海马内注射纤丝状Aβ42 ,采用免疫组织化学染色方法 ,显示PS2 0 2 tau的表达情况 ,并进行图像分析。结果　纤丝状Aβ42 注射组双侧海马PS2 0 2 tau的表达明显高于正常组和双蒸水注射组 ,两侧海马PS2 0 2 tau的表达没有明显差异。结论　纤丝状Aβ42 能使PS2 0 2 tau的表达增加 ,提示它具有诱导tau蛋白超磷酸化的效应。     

Denervation study of synapses of organ of corti of old world monkeys

Fine structural characteristics of synapses in the spiral organ of Corti were examined, with reference to differences between inner and outer haircell systems, and to location of neurons of origin of efferent axons. Surgical interruption of crossed olivocochlear bundle, of vestibular nerve, of facial nerve, and excision of superior cervical ganglia were used to determine the pathways of efferent axons. Interruption of the vestibular nerve near the brainstem results in degeneration of all efferent terminals on outer hair cells. Mid-line lesions at, and caudal to, the facial colliculus result in degeneration of about half of these efferent terminals. Efferent synaptic bulbs to the inner hair-cell system are small, of the order of one micron, and form type 2 junctions with afferent dendrites. They tend to have more large dense-core vesicles (about 80 nm) than the large efferent terminals of the outer hair-cell system, and appear to be the terminals of axons in the habenula perforata, which exhibit varicosities laden with large dense core vesicles. The varicosities are unaffected by excision of the superior cervical ganglia. So far as our material can reveal, it appears that the varicosities in the habenula perforata do not survive vestibular root interruption, nor do the efferent processes in the internal spiral bundle or at the base of inner hair cells. Most interestingly, the afferent processes of the inner hair-cell system, as identified for example by their relation to pre-synaptic bodies in the inner hair cells, are subject to a trans-synaptic reaction after severance of the vestibular root. They undergo a dramatic cytological transformation, characterized by increase of volume, engorgement with microtubules, microfilaments, microvesicles of various sizes, and clusters of lysosomes. Thus, both the efferent and afferent terminals of the inner hair-cell system show marked cytological differences from the corresponding terminals of the outer hair cell system.     

Mechanism of action of tubocurarine on nicotinic cholinoreceptors of neurons of the sympathetic ganglia of rats

Tubocurarine (Tc) effect on membrane currents elicited by acetylcholine (ACh) was studied in isolated superior cervical ganglion neurons of rat using patch-clamp method in the whole-cell recording mode. The "use-dependent" block of ACh current by Tc was revealed in the experiments with ACh applications, indicating that Tc blocked the channels opened by ACh. Mean lifetime of Tc-open channel complex, tau, was found to be 9.8 +/- 0.5 s (n = 7) at -50 mV and 20-24 degrees C. tau exponentially increased with membrane hyperpolarization (e-fold change in tau corresponded to the membrane potential shift by 61 mV). Inhibition of the ACh-induced current by Tc (3-30 microM/1) was completely abolished by membrane depolarization to the level of 80-100 mV. Inhibition of ACh-induced current was augmented at increased ACh doses. It is concluded that the open channel block produced by Tc is likely to be the only mechanism for Tc action on nicotinic acetylcholine receptors in superior cervical ganglion neurons of rat.     

The effect of age of onset of PD on risk of dementia

Background Dementia occurs in the majority of patients with Parkinson’s disease (PD). Late onset of PD has been reported to be associated with a higher risk for dementia. However, age at onset (AAO) and age at baseline assessment are often correlated. The aim of this study was to explore whether AAO of PD symptoms is a risk factor for dementia independent of the general effect of age. Methods Two community-based studies of PD in New York (n = 281) and Rogaland county, Norway (n = 227) and two population-based groups of healthy elderly from New York (n = 180) and Odense, Denmark (n = 2414) were followed prospectively for 3–4 years and assessed for dementia according to DSM-IIIR. All PD and control cases underwent neurological examination and were followed with neurological and neuropsychological assessments. We used Cox proportional hazards regression based on three different time scales to explore the effect of AAO of PD on risk of dementia, adjusting for age at baseline and other demographic and clinical variables. Findings In both PD groups and in the pooled analyses, there was a significant effect of age at baseline assessment on the time to develop dementia, but there was no effect of AAO independent of age itself. Consistent with these results, there was no increased relative effect of age on the time to develop dementia in PD cases compared with controls. Interpretation This study shows that it is the general effect of age, rather than AAO that is associated with incident dementia in subjects with PD. Received in revised form: 22 December 2005     

Limits of deinstitutionalization--perspectives of relatives of psychiatric patients

After a hopeful beginning, the social process of the reintegration of those with severe mental illness has come to a standstill. I am led to wonder whether "the community" really wants to live together with people suffering from severe mental illness, and if so, how closely? As long as the medical treatment of mental illness provided by the general practitioners is fundamentally deficient, as they are not able to prescribe the necessary interventions--such as out-patient psychiatric nursing, and service providers in the out-patient sector are content with offering increasingly intensive forms of care for the less seriously ill at the cost of the Social Welfare System--the reintegration of those with serious mental illness remains an illusion--which is mainly to the benefit of providers of residential care in homes and hostels.     

Summary of Legislation of 1933 of interest to the Department of Mental Hygiene

Psychiatric Quarterly -