慢性应激抑郁模型大鼠强迫游泳后海马中HsP70的表达

目的研究慢性应激对强迫游泳大鼠海马神经元热休克蛋白70(Hsp70)表达的影响。方法将50 只大鼠随机分为实验组和对照组各25只。实验组大鼠通过21天的应激刺激制作抑郁动物模型,此期间对照组大 鼠正常饲养。此后所有大鼠逐只进行急性强迫应激刺激。采用特异性抗体的免疫组织化学方法,观察2组大鼠在 强迫游泳后2 h、6 h、18 h、24 h和48 h各时点海马神经元Hsp70的表达情况。结果慢性应激抑郁大鼠模型接受 急性强迫游泳应激后,海马CA3区和齿状回(DG)内Hsp70蛋白的表达较对照组强迫游泳后显著降低(P<0．05)。 结论慢性应激使大鼠在急性强迫游泳应激后海马CA3区和DG内Hsp70的表达降低。     

慢性应激对大鼠学习记忆功能和海马神经细胞粘附分子表达的影响

目的观察慢性应激对大鼠学习记忆功能和海马神经细胞粘附分子（NCAM）表达的影响，探讨海马NCAM表达在慢性应激影响学习记忆机制的作用。方法20只SD大鼠随机被分为对照组（10只）和慢性应激组（10只），后者以束缚浸水应激方式连续应激21天，三周后行水迷宫实验，并用免疫组化法测定大鼠的脑海马区NCAM的表达。结果应激组在水迷宫测试中寻找水中隐藏平台的潜伏期为（7．1±8．9）秒，对照组为（12．3±4．2）秒，差异有统计学意义；穿越平台次数：应激组为（8．4±1．1）次，对照组为（12．5±1．9）次，差异有统计学意义。应激组海马CA3区NCAM的表达：25．2％±3．6％，对照组为37．9％±5．1％，差异有统计学意义。结论慢性应激对大鼠的学习记忆功能有抑制作用。其机制可能与应激抑制海马CA3区NCAM表达有关。     

盐酸美金刚对癫痫大鼠海马GSK-3β表达的影响

目的探讨盐酸美金刚(memantine,MN)对戊四氮(pentylenetetrazol,PTZ)点燃慢性癫痫大鼠学习记忆能力及海马中糖原激酶合酶-3β(glycogen synthase kinase-3,GSK-3β)表达的影响。方法动物分为正常对照组(NC)、癫痫组(PTZ)、盐酸美金刚干预组(MN),采用PTZ致痫模型,Morris水迷宫检测各组大鼠空间学习记忆能力,Western blot和RT-PCR方法检测大鼠海马GSK-3β、P-GSK-3β蛋白和GSK-3βmRNA表达。结果 PTZ组大鼠空间学习记忆能力受损,其海马中P-GSK-3β蛋白表达明显减少(P<0.05),GSK-3β蛋白和mRNA表达无变化(P>0.05)。MN组大鼠学习记忆能力明显好转,其海马中P-GSK-3β蛋白表达明显升高(P<0.05),GSK-3β蛋白和mRNA表达无变化(P>0.05)。结论 PTZ点燃慢性癫痫大鼠学习记忆受损,其海马组织中P-GSK-3β蛋白表达明显降低,P-GSK-3β可能参与癫痫后认知功能障碍发病机制;盐酸美金刚可提高P-GSK-3β蛋白表达水平,从而改善癫痫大鼠学习记忆能力。     

文拉法辛对慢性应激抑郁大鼠海马区可塑性相关蛋白mRNA表达的影响

目的 观察文拉法辛对慢性应激抑郁大鼠海马区可塑性相关蛋白mRNA表达的影响.方法 用慢性不可预见应激(CUS)方法建立大鼠抑郁模型,给予2种剂量(5 mg/kg体质量和10 mg/kg体质量)的抗抑郁剂文拉法辛,用反转录-聚合酶链反应检测大鼠海马区脑源性神经营养因子(BDNF)、转录因子环磷腺苷反应元件结合蛋白(CREB)及神经细胞黏附分子(NCAM)mRNA表达的变化.正常对照组、抑郁模型组、抑郁模型后注射生理盐水14 d组及28 d组各10只,抑郁模型后小剂量文拉法辛(5 mg/kg体质量)治疗14 d组及28 d组、抑郁模型后大剂量文拉法辛(10 mg/kg体质量)治疗14 d组及28 d组各11只.结果 抑郁模型大鼠体质量、蔗糖水消耗量及旷场实验结果均明显低于正常对照组,提示抑郁模型大鼠在第28天建立成功.慢性不可预见应激28 d后,抑郁模型大鼠海马区BDNF(0.18±0.09)、CREB(0.10±0.05)及NCAM(0.08±0.04)mRNA表达水平均明显低于正常组[吸光度比值分别为(0.41±0.12)、(0.26±0.05)及(0.24±0.08);P均＜0.05 ].5 mg/kg体质量文拉法辛明显增加海马区3种可塑性相关蛋白mRNA的表达;10 mg/kg文拉法辛轻度降低海马区3种可塑性相关蛋白mRNA的表达.结论 文拉法辛在一定剂量范围内调节海马区的神经可塑性,BDNF、CREB及NCAM在抑郁症的病因及治疗中发挥重要作用.     

应激对高血压大鼠认知障碍的影响及其机制

目的 研究应激对高血压大鼠认知障碍的影响及机制.方法 62只大鼠被随机分为应激组与非应激组、对照组,前2组用双肾双夹法制作高血压模型大鼠,其中应激组再接受强迫游泳应激.应激10周后以跳台实 验测量大鼠的学习记忆能力,然后电镜下观察海马CA3区血管、神经元和突触结构的变化.结果 ①应激组大鼠血压较非应激组和对照组大鼠升高明显(P<0.05);②学习测验中,应激组跳台实验的错误次数和反应时间均高于非应激组和对照组(P<0.05);记忆测验中,应激组、非应激组和对照组的错误次数递减而潜伏期依次增加,两两差异均有统计学意义(P<0.05).③应激组的海马C3区突触曲率、活性区长度和突触后膜致密物质厚度较非应激组小(P<0.05).结论 应激可能是血管性认知障碍的危险因素之一.     

慢性应激对大鼠海马CA3区锥体细胞顶树突细胞骨架的效应及其机制研究

目的 探讨慢性强迫游泳应激对大鼠海马CA3区锥体细胞顶树突细胞骨架的效应及可能的机制.方法 将16只雄性Sprague-Dawley大鼠(2月龄),随机分为对照组和应激组(强迫游泳,20 min/d,共4周),每组8只.用常规透射电镜观察两组大鼠海马CA3区锥体细胞顶树突细胞骨架,用免疫组织化学方法定量测定锥体细胞内磷酸化微管相关蛋白2(MAP2)表达水平.结果 (1)海马CA3区锥体细胞顶树突内细胞骨架的变化:对照组纵切面显示微管排列整齐、连续,呈平行状;横切面显示环状微管完整、规则,分布均匀;线粒体嵴清晰.应激组纵切面显示微管断裂,平行微管间距离变宽;横切面显示微管环不完整,单体分布不均匀;线粒体嵴模糊,偶见空泡样变性.(2)海马CA3区锥体细胞磷酸化MAP2的表达:应激组大鼠平均灰度值(145.0±4.4)低于对照组(149.3±1.8)(P＜0.05),表达的阳性细胞数[(40.36±1.36)个/视野]少于对照组[(42.73±1.56)个/视野;P＜0.01].结论 慢性强迫游泳应激可导致大鼠海马CA3区锥体细胞顶树突内细胞骨架的损害,这一效应可能通过增加磷酸化MAP2的表达实现.     

急性应激对大鼠脑内5-羟色胺1A受体mRNA表达的影响

目的 探讨急性应激对大鼠脑内5-羟色胺1A(5-HT1A)受体mRNA表达的影响。方法 将12只雄性Sprague-Dawley大鼠随机分为应激组和对照组,每组6只。根据5-HT1A受体互补DNA(eDNA)序列合成相应的特异性引物,用聚合酶链反应(PCR)法观察强迫游泳应激后3 h大鼠海马、下丘脑和中脑5-HT1A受体mRNA表达,并测定各脑区阳性电泳条带密度与β肌动蛋白(β-actin)密度的百分比。结果 应激后3 h,大鼠下丘脑5-HT1A受体mRNA表达相对水平为(64.3±6.7)％,显著低于对照组(78.9±8.7)％(t=3.263.P<0.05);海马、中脑5-HT1A受体mRNA表达相对水平分别为41.5％±7.1％、37.4％±5.6％,均分别显著低于对照组64.8％±9.6％、63.9％±6.3％(t分别为4.782、7.701,P均<0.01)。结论 急性应激后大鼠海马、下丘脑和中脑5-HT1A受体mRNA的表达降低。     

西酞普兰对慢性应激大鼠海马CA1和CA3区神经细胞B细胞淋巴瘤/白血病-2及Bcl相关蛋白表达与凋亡的影响

目的 探讨西酞普兰对慢性应激大鼠海马CA1、CA3神经细胞B细胞淋巴瘤/白血病-2(Bcl-2)、Bcl相关蛋白(Bax)表达和凋亡的影响.方法 40只雄性Sprague-Dawley大鼠随机分为对照组、应激组(生理盐水灌胃)、处理1～3组[分别以不同剂量(1 mg·kg-1·d-1、4 nag·kg-1·d-1、8 mg·kg-1·d-1)氢溴酸西酞普兰灌胃],每组8只.采用强迫游泳制造慢性应激模型,用大鼠悬尾实验、力竭实验进行行为学观察,免疫组织化学检测Bel-2、Bax表达水平.脱氧核糖核苷酸末端转移酶介导的缺口末端标记法检测细胞凋亡.尼康图像分析软件测量分析Bcl-2、Bax阳性表达、凋亡阳性细胞数量及积分吸光度值.结果 应激组静止不动时间[(279±53)s]长于对照组[(182±35)s]及处理1～3组[(200±71)s,(159±59)s,(165±54)s];挣扎次数[(20±3)次]少于对照组[(24±3)次]及处理1～3组[(37±16)次,(32±10)次,(24±4)次];力竭时间[(38.3±5.1)min]长于对照组[(22.9±1.8)min]、短于处理1～3组[(54.4±2.9)min,(69.3±17.6)min,(46.4±4.0)min];差异均有统计学意义(P<0.05或0.01).与对照组比较,应激组CA1、CA3神经细胞Bcl-2表达变弱、Bax表达增强、凋亡细胞增多,差异均有统计学意义(P<0.05或0.01).与应激组比较,处理1～3组Bcl-2表达增强、Bax表达变弱、凋亡细胞减少,差异均有统计学意义(P<0.05或0.01).处理组1～3组的部分Bcl-2/Bax表达、凋亡阳性细胞数量与对照组的差异有统计学意义(P<0.05),但IA值的差异均无统计学意义(P均>0.05).结论 慢性应激可影响大鼠海马CAI、CA3神经细胞Bcl-2、Bax表达水平,促进细胞凋亡;西酞普兰可影响慢性应激大鼠海马CAI、CA3神经细胞Bcl-2、Bax表达水平,拈抗细胞凋亡.     

慢性冷水游泳应激对大鼠海马、前脑皮层神经颗粒素含量的影响

目的探讨慢性应激对大鼠海马和前脑皮层神经颗粒素(NG)含量的影响。方法将雄性SD大鼠随机分为应激组(予10℃冷水游泳应激,共2周)、装置对照组和正常对照组,每组10只。于应激前后测量三组大鼠的体质量变化情况,并记录每天应激过程中应激组和装置对照组的排便量以考察应激的强度,应激后以Westernblotting方法测定海马和前脑皮层中的NG含量(以NG含量与βActin含量的比值表示)。结果(1)应激前后,三组大鼠的体质量比较,差异均无统计学意义(P>0.05),但应激组的体质量增长相对缓慢;(2)应激第4—14天应激组的排便量多于装置对照组(P<0.01);(3)应激组和装置对照组海马的NG含量[分别为(0.66±0.13)和(0.94±0.26)]低于正常对照组[(1.93±0.53)],差异有统计学意义(P<0.01);(4)应激组前脑皮层的NG含量[(0.45±0.00)]低于装置对照组和正常对照组[分别为(2.76±1.74)和(2.87±1.63)],差异有统计学意义(P<0.01);(5)应激组海马NG含量高于前脑皮层(P<0.01);装置对照组海马NG含量低于前脑皮层(P<0.01);正常对照组海马与前脑皮层NG含量的差异无统计学意义。结论慢性应激导致海马和前脑皮层NG含量显著下降;对于时程长、程度严重、适应不良的冷水游泳应激,前脑皮层受损比海马更为严重;而对于时程长、程度微弱的装置应激,海马则比前脑皮层更为敏感。     

脑缺血与慢性应激对依赖海马的学习记忆的影响

目的 对比脑缺血与慢性应激所致认知损害及海马病变的强弱,为临床改善脑卒中后认知障碍(poststroke cognitive impairment,PSCI)提供参考.方法 40只成年雄性SD大鼠平均分为4组:对照组、应激组、缺血组与缺血加应激组,缺血手术采用改良的选择性大脑中动脉栓塞术;应激处理采用连续3周的慢性不可预见性温和应激;Moms水迷宫实验评价依赖海马的学习记忆功能;免疫组织化学染色及半定量RT-PCR观察海马CA3区脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)的表达变化.结果 应激或缺血均可使大鼠学习功能明显下降,表现为与同时点对照组比较,逃避潜伏期显著延长,二者的综合作用更明显.慢性应激对学习功能的影响强于脑缺血损伤.应激或缺血均减弱记忆功能,但二者的作用差异无统计学意义.与对照相比,缺血显著增加海马CA3区BDNF的表达(27.0±2.5与20.1±2.1),应激降低BDNF的表达(15.2±1.8与20.1±2.1),二者综合作用仍显著降低BDNF的表达(8.2±1.5),差异均具有统计学意义(F=52.87,P＜0.05).结论 缺血与应激均降低大鼠学习记忆功能,应激对认知功能的损害高于缺血,而缺血与应激的综合作用对认知功能损害与抑制BDNF表达作用更明显,提示进行PSCI的综合治疗时,要重视心理社会应激干预和抑郁状态的改善.     

Bibliography of officers of department of mental hygiene

Psychiatric Quarterly -     

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     

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.     

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.     

Sense of coherence as a predictor of subjective state of health: results of 4 years of follow-up of adults

A number of cross-sectional population studies have shown that a strong sense of coherence (SOC) is associated with various aspects of good perceived health. The association does not seem to be entirely attributable to underlying associations of SOC with other variables, such as age or level of education. OBJECTIVE: The aim of the study reported here was to determine whether SOC predicted subjective state of health. METHODS: The study was carried out as a two-way panel mail survey of 1976 individuals with 4 years interval for two collections of data. The statistical method used was multivariate cumulative logistic modeling. Age, initial subjective state of health, initial occupational training level, and initial degree of social integration were included as potential explanatory variables. RESULTS: A strong SOC predicted good health in women and men. CONCLUSIONS: SOC can be interpreted as an autonomous internal resource contributing to a favorable development of subjective state of health. SOC data should, however, be regarded as complementary to and not a substitute for information already known to be associated with increased risk of future ill health.