大鼠局灶性脑缺血预处理后XBP-1表达的变化

目的 观察缺血预处理对大鼠脑缺血再灌注后X盒结合蛋白1(XBP-1)mRNA及其蛋白表达的影响.方法 SD大鼠60只,随机分为假手术组(SO)、脑缺血再灌注组(MCAO)、脑缺血预处理组(BIP)3组,每组按照再缺血后12h、1d、2d、3d4个时间点分为4个亚组.采用二次线栓法制备大鼠局灶性脑缺血预处理模型,用实时荧光定量PCR和Western blot法观察再缺血后各个时间点XBP-1 mRNA及其蛋白的表达变化.结果 MCAO组XBP-1 mRNA及其蛋白表达均于缺血再灌注后12h开始明显上升,24h达高峰(P＜0.01),随再灌注时间延长其表达逐渐下降,但仍保持较高表达水平(P ＜0.01);BIP组较MCAO组XBP-1 mRNA及其蛋白表达明显升高(P＜0.05,P＜0.01).结论 脑缺血预处理可能通过诱导XBP-1表达发挥其神经保护作用.     

大鼠局灶性脑缺血再灌注后FADD mRNA及其蛋白的表达变化

目的观察大鼠脑缺血再灌注后缺血半暗带皮质内Fas死亡结构域相关蛋白（FADD）mRNA及蛋白的表达变化。方法用半定量的逆转录PCR（RT-PCR）法检测缺血2h再灌注不同时间点缺血半暗带皮质内FADD mRNA的表达,Western blot检测FADD蛋白表达的变化。结果缺血半暗带脑皮质内FADD mRNA及其蛋白的表达于缺血灌注后3h明显升高,再灌注后12h达高峰（P＜0．01）,至再灌注后24h明显下降。结论脑缺血再灌注后缺血半暗带皮质内FADD mRNA及蛋白表达均明显增加,提示FADD可能在脑缺血再灌注损伤中发挥重要作用。     

大鼠局灶性脑缺血预处理后激活转录因子4mRNA及其蛋白表达的变化

目的 观察缺血预处理对大鼠脑缺血再灌注后激活转录因子4 (ATF4) mRNA及其蛋白表达的影响.方法 SD大鼠120只,随机分为假手术组(SO)、脑缺血再灌注组(MCAO)、脑缺血预处理组(BIP)3组,每组按照再缺血后12h、ld、2d、3d4个时间点分为4个亚组.采用二次线栓法制备大鼠局灶性脑缺血预处理模型,用原位杂交法和Western blot法观察再缺血后各个时间点ATF4 mRNA及其蛋白表达的变化.结果 MCAO组12hATF4mRNA及其蛋白表达均达高峰(P＜0.01),随再灌注时间延长其表达逐渐下降;BIP组较MCAO组ATF4 mRNA及其蛋白表达均明显降低(P＜0.05,P＜0.01).结论脑缺血预处理可能通过抑制ATF4表达发挥其神经保护作用.     

大鼠局灶性脑缺血预处理后蛋白激酶样内质网激酶及葡萄糖调节蛋白78表达的变化

目的 观察缺血预处理对大鼠脑缺血再灌注后蛋白激酶样内质网激酶(PERK)和葡萄糖调节蛋白( GRP78) mRNA及其蛋白表达和神经元凋亡的影响.方法 SD大鼠120只,随机分为假手术组、脑缺血再灌注组(MCAO)、腩缺血预处理组(BIP),每组按照再缺血后12h,1、2、3d4个时间点分为4个亚组.采用二次线栓法制备大鼠局灶性脑缺血预处理模型,分别用原位杂交法和Western blot法观察再缺血后各个时间点PERK和GRP78 mRNA及其蛋白的表达变化,用流式细胞术检测神经细胞凋亡率.结果 ①MCAO组12 h PERK mRNA表达达高峰,随再灌注时间延长其表达逐渐下降;BIP组缺血各时间点其表达水平均明显下降.MCAO组PERK蛋白表达于缺血再灌注后12 h开始明显上升,24 h达高峰,2d后表达开始减弱;BIP组较MCAO组PERK表达明显降低.②MCAO组12 h GRP78 mRNA及其蛋白表达均达高峰,随再灌注时间延长其表达逐渐下降;BIP组较MCA0组GRP78 mRNA及其蛋白各时间点表达均明显升高(mRNA:12 h:136.70±9.53,F=32.265;24h:147.54±9.97,F=54.920;2 d:158.16±9.44,F=45.374;3 d:165.85±10.26,F=16.493,均P＜0.05;蛋白:12 h:1.319±0.116,F=5.619,P＜0.05;24 h:1.226±0.108,F=33.742,P＜0.01;2 d:1.183±0.112,F=46.556,P＜0.01;3 d:1.115±0.098,F=11.730,P＜0.05).③MCAO组12 h细胞凋亡发牛率明显增加,24h时达到高峰,以后逐渐下降;BIP组各个时间点神经元凋亡发牛率较MCAO组明显降低.结论 脑缺血预处理可能通过抑制内质网应激后PERK表达和诱导GRP78表达发挥其神经保护作用.     

垂体腺苷酸环化酶激活肽对大鼠脑缺血再灌注后细胞间黏附分子表达的影响

目的 探讨大鼠局灶性脑缺血再灌注时ICAM-1在PACAP脑保护机制中的作用.方法 采用大脑中动脉线栓法建立局灶性脑缺血再灌注模型,对54只大鼠随机分为假手术组、缺血再灌注组和PACAP组,在大鼠脑缺血2h后进行再灌注.在再灌注2h、24h、48h,应用免疫组化法检测脑组织ICAM-1的表达.结果 局灶性脑缺血再灌注后,与假手术组比较,ICAM-1的表达量显著增加,灰度值分别为2h128.67±1.51(P＜0.05)、12h168.67±2.66(P＜0.01)、24h173.17±2.51(P＜0.01);应用PACAP与缺血再灌注组比较,ICAM-1表达的峰值明显降低,灰度值分别为123.00±2.98、143.67±2.42、144.67±3.01(P＜0.01.结论 PACAP能抑制大鼠局灶性脑缺血再灌注时ICAM-1的表达,进而抑制炎症反应,这可能是其脑保护作用之一.     

ATP敏感性钾通道开放剂对大鼠脑缺血再灌注后caspase-12 mRNA及蛋白表达的影响

目的 观察ATP敏感性钾通道(KATP)开放剂对大鼠脑缺血再灌注后caspase-12mRNA和蛋白表达的影响,探讨内质网信号通路是否参与了KATP开放剂对脑缺血后神经元凋亡的抑制机制.方法 200只Wistar雄性大鼠随机分为假手术组,缺血再灌注组,开放剂组及阻断剂组.应用线栓法制备大鼠大脑中动脉缺血再灌注模型,分别应用免疫组化染色、RT-PCR技术检测脑缺血再灌注后各组caspase-12蛋白及mRNA的表达.结果 在缺血再灌注组,开放剂组及阻断剂组,随着缺血再灌注时间的延长,caspase-12mRNA及蛋白的表达逐渐增高,在缺血再灌注后24 h达高峰.开放剂组caspase-12 mRNA及蛋白表达在各时间点均显著少于缺血再灌注组及阻断剂组(P＜0.05或P＜0.01).阻断剂组各时间点与缺血再灌注组相比均无显著性差异(P＞0.05).结论 KATP开放剂可能通过抑制内质网信号通路,减少神经元凋亡,降低脑缺血再灌注损伤.     

腺苷预处理对大鼠局灶性脑缺血再灌注损伤的脑保护作用

目的 观察腺苷预处理对大鼠局灶性脑缺血再灌注损伤的改善作用及脑保护机制.方法 线栓法建立大鼠局灶性脑缺血2 h后再灌注损伤模型;SD大鼠60只,随机分为假手术组(F组),缺血再灌注组(IR组),腺苷预处理组(AP组),每组20只;通过HE 染色在光镜下观察神经细胞损伤变化,免疫组化法检测Bax蛋白的阳性表达.结果 光镜下,假手术组(F组)神经细胞结构正常,腺苷预处理组(AP组)和缺血再灌注组(IR组)均有不同程度的缺血再灌注损伤,腺苷预处理组较缺血再灌注组损伤轻;假手术组Bax蛋白表达极弱,缺血再灌注组和腺苷预处理组在脑缺血再灌注后2 h接近缺血核心区出现Bax蛋白阳性表达,6 h后表达增多,24 h达到高峰,72 h开始减少.与假手术组相比,腺苷预处理组和缺血再灌注组Bax蛋白阳性细胞数显著增多(P＜0.05);与缺血再灌注组相比,腺苷预处理组Bax蛋白阳性细胞数显著减少(P＜0.05).结论 腺苷对大鼠局灶性脑缺血再灌注损伤有保护作用,腺苷可通过下调Bax蛋白的表达发挥脑保护作用.     

三磷酸腺苷敏感性钾通道开放剂对大鼠脑缺血再灌注后神经元凋亡及天冬氨酸特异性半胱氨酸蛋白酶-8表达的影响

目的 研究三磷酸腺苷敏感性钾通道(KATP)开放剂对大鼠脑缺血再灌注后神经元凋亡和天冬氨酸特异性半胱氨酸蛋白酶(caspase)-8 表达的影响.方法 200只Wistar雄性大鼠随机分为假手术组、对照组、KATP开放剂预处理组(开放剂组)及KATP开放剂 阻断剂预处理组(阻断剂组).应用线栓法制备大鼠大脑中动脉缺血再灌注模型,应用原位末端标记法(TUNEL)、免疫组化染色、逆转录-聚合酶链反应(RT-PCR)技术检测脑缺血再灌注后各组脑组织凋亡细胞数和caspase-8 mRNA及蛋白的表达.结果 (1)缺血再灌注12 h、24 h、48 h、72 h各时间点凋亡细胞数,开放剂组较对照组和阻断剂组显著减少(P＜0.05～0.01),阻断剂组与对照组间各时间点差异无统计学意义.(2)缺血再灌注12 h、24 h、48 h、72 h各时间点caspase-8蛋白表达,开放剂组显著低于对照组和阻断剂组(P＜0.05～0.01),阻断剂组与对照组间各时间点差异无统计学意义.(3)缺血再灌注各时间点caspase-8 mRNA表达,开放剂组均显著低于对照组和阻断剂组(均P＜0.01), 阻断剂组与对照组各时间点相比差异无统计学意义.结论 KATP开放剂能显著减少脑缺血再灌注后神经元凋亡和caspase-8 mRNA及蛋白的表达;KATP开放剂可能通过抑制死亡受体通路发挥脑保护作用.     

大鼠脑缺血再灌注后Nogo-A及其受体mRNA和蛋白表达的变化

目的探讨脑缺血再灌注后大鼠缺血中心区及周围区大脑皮质髓鞘相关的抑制分子Nogo-A及其受体NgR的mRNA和蛋白表达的变化规律及意义。方法采用线栓法制作大鼠脑缺血再灌注模型,分为假手术对照组、缺血2h再灌注6h、12h、24h、48h、72h、7d和14d组．通过HE染色进行病理观察,逆转录一聚合酶链反应(RT-PCR)的方法检测mRNA,免疫组织化学的方法检测蛋白表达,观察脑缺血再灌注后缺血中心区及周围区大脑皮质Nogo-A及其受体NgR的变化。结果Nogo-A mRNA及蛋白表达在缺血中心区6h即有下降(与对照组相比,P＜0．05),并随再灌注时间延长表达逐渐减少,24h降低最为明显并持续至14d；而缺血周边区,再灌注48h前无显著性变化．72h表达增加(与对照组相比,P＜0．05),7d增加更为显著,14d降至正常。NgR mRNA及蛋白表达在缺血中心区再灌注6h后开始下降(与对照组相比,P＜0．05),48h降低最为明显；而缺血周围区NgR mRNA及蛋白表达在各个时间点无显著变化(P＞0．05)。结论脑缺血后灶周Nogo-A mRNA及蛋白表达增加持续至再灌注后7d以上,针对其表达的规律进行干预可能成为脑梗死后改善轴突生长的有效措施；灶周NgR的表达无显著变化,显示Nogo-A的作用尚有其他受体介导。     

大鼠局灶性脑缺血预处理后IRE1表达的变化

目的观察缺血预处理对大鼠脑缺血再灌注后肌醇需求激酶1(IRE1)mRNA及其蛋白表达和神经元凋亡的影响。方法 SD大鼠120只,随机分为假手术组(SO)、脑缺血再灌注组(MCAO)、脑缺血预处理组(BIP),每组按照再缺血后12 h、1 d、2 d、3 d 4个时间点分为4个亚组。采用二次线栓法制备大鼠局灶性脑缺血预处理模型,分别用实时荧光定量PCR和Western blot法观察再缺血后各个时间点IRE1 mRNA及其蛋白表达的变化,用流式细胞术检测神经细胞凋亡率。结果 (1)MCAO组12 h IRE1 mRNA及其蛋白表达开始明显升高,24 h达高峰(P0.01),随再灌注时间延长其表达逐渐下降;BIP组较MCAO组IRE1 mRNA及其蛋白各时间点表达均明显升高(P0.05,P0.01)。(2)MCAO组12 h细胞凋亡发生率明显增加,24 h时达到高峰(P0.01),以后逐渐下降;BIP组各个时间点神经元凋亡发生率较MCAO组明显降低(均P0.05)。结论脑缺血预处理可能通过诱导内质网应激后IRE1的表达发挥其神经保护作用。     

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 -