缺血缺氧新生大鼠脑内原位神经干细胞的增殖与分化：可通过针刺任脉、督脉及膀胱经实现？

[摘要] 目的 检测针刺任脉、督脉及膀胱经对新生儿缺血缺氧性脑病模型鼠脑内神经干细胞的影响,分析针刺诱导神经干细胞增殖、分化的机制,为临床针刺治疗新生儿缺血缺氧性脑病提供新的细胞学理论依据。方法 新生7天SD大鼠结扎左侧颈总动脉并缺氧2小时制作新生鼠缺血缺氧性脑病模型。实验动物共分三组：针刺组、对照组和正常组。针刺组每天针刺任脉、督脉及膀胱经治疗一次。对照组及正常组不作针刺处理。各组动物每天两次腹腔注射Brdu用于标记脑内神经干细胞增殖情况。分别于模型建立后3d、7d、14d和28d取脑组织行抗Brdu的免疫组化染色,并于模型建立后40d行免疫荧光双标,分别观察各组动物海马及皮层Brdu阳性细胞数目、形态、分布以及分化情况; 并比较他们之间的差异。结果 抗Brdu的免疫组化染色显示针刺任脉、督脉及膀胱经治疗第3天及第7天时针刺组动物皮层及海马的Brdu阳性细胞数目和对照组相比,差别无统计学意义;针刺治疗第14天及第28天时针刺组动物皮层及海马的Brdu阳性细胞数目明显比对照组多,差别有统计学意义。针刺后第40天免疫荧光双标显示大部分Brdu阳性细胞和神经元标记物NSE共存,少部分和星形胶质细胞标记物GFAP共存。结论 针刺任脉、督脉及膀胱经能促进HIE模型鼠皮层及海马神经干细胞的增殖潜能;针刺任脉、督脉及膀胱经治疗后新生的神经干细胞大部分分化为神经元,提示针刺后新生的神经细胞有可能有效地补充在缺血缺氧中丧失的神经元,并能促进HIE动物功能的恢复。     

丁咯地尔对慢性脑缺血大鼠海马CA1区星形胶质细胞及认知障碍的影响

目的研究丁咯地尔对慢性脑缺血大鼠海马CA1区星形胶质细胞和认知障碍的影响。方法采用双侧颈总动脉永久性结扎制备慢性脑缺血模型,治疗组大鼠给与丁咯地尔灌胃,免疫组化法多克隆抗血清GFAP标记海马CA1区星形细胞,用Y-型迷宫测定大鼠的认知功能变化。实验研究为持久性2VO2个月。结果慢性脑缺血2个月后大鼠海马CA1区星形胶质细胞大量增生肥大,认知能力明显下降,丁咯地尔治疗后,星形胶质细胞的活动明显减少,认知功能明显提高。结论丁咯地尔能抑制慢性脑缺血大鼠海马CA1区星形胶质细胞反应,改善其认知功能障碍。     

EGb761对慢性脑缺血大鼠脑组织神经胶质细胞的影响

目的 探讨EGb761(银杏叶提取物)对慢性脑缺血大鼠脑组织神经胶质细胞的影响.方法 将雄性SD大鼠随机分为假手术组、单纯缺血组、EGb761干预组.制备慢性脑缺血大鼠模型,药物干预12周后,免疫组化方法分别检测各组大鼠脑组织中星形胶质细胞和少突胶质细胞的表达.结果 EGb761干预组大鼠的海马、胼胝体、皮质CNPase阳性细胞表达明显高于单纯缺血组,而海马、胼胝体、皮质GFAP阳性细胞表达明显低于单纯缺血组(P<0.05),差异有统计学意义.结论 慢性脑缺血时,EGb761对少突胶质细胞缺血性反应有保护作用,同时减少反应性星形胶质细胞增生.     

胀亡-持续性局灶脑缺血星形胶质细胞的死亡方式

目的动态观察大鼠持续性局灶脑缺血后星形胶质细胞的形态学变化,探讨星形胶质细胞的死亡方式.方法将48只SD大鼠随机分为免疫组化组、免疫组化对照组、电镜实验组和电镜实验对照组.采用颈内动脉线栓并环扎的方法建立持续性局灶脑缺血模型.免疫组化组和电镜实验组大鼠按照缺血时间（3h、6h、12h、24h、48h）平均随机分为5个亚组.对照组为术后24h取脑.免疫组化标本采用HE染色及TUNEL-GFAP双染.电镜标本在中心区、边缘区分别取材、染色后,透射电镜观察.结果随着时间的延长,脑缺血中心区及边缘区星形胶质细胞逐渐出现核肿胀、染色质分散、边聚、空泡变,核膜破溃,染色质溢出.随着缺血时间延长,中心区GFAP阳性细胞数逐渐减少,直至基本消失.缺血边缘区则可见到GFAP阳性细胞数量逐渐增多.TUNEL-GFAP双染未见阳性细胞.结论持续局灶脑缺血后,星形胶质细胞未见凋亡,推测胀亡是星形胶质细胞主要的死亡方式.     

rTMS促进大鼠局灶性脑缺血海马内源性神经干细胞分化的研究

目的探讨重复经颅磁刺激（rTMS）对局灶性脑缺血大鼠海马内源性神经干细胞分化的影响。方法线栓法制备大鼠大脑中动脉闭塞（MCAO）模型,随机分为脑缺血自然恢复组和rTMS治疗组,用荧光显微镜和共聚焦显微镜观察缺血14d、28d后各组大鼠海马中5-溴脱氧尿核苷（BrdU）与神经元特异核蛋白（NeuN）、神经胶质酸性蛋白（GFAP）共同标记的阳性细胞,并在高倍荧光显微镜下对双标阳性细胞计数。结果脑缺血后14d、28d,rTMS治疗组大鼠海马BrdU／NeuN双标阳性细胞数量分别为17．12±2．91、23．20±5．97,较相应自然恢复组12．96±2．79、15．92±2．52明显增加,两组同一时间点组间比较有统计学差异（P〈0．01）。而脑缺血后14d、28d,rTMS治疗组大鼠海马BrdU／GFAP双标阳性细胞数量分别为30．48±4．58、36．48±4．90,较相应自然恢复组37．44±3．58、43．60±5．96减少,两者相比有统计学差异（P〈0．05）。结论局灶性脑缺血大鼠海马增殖的内源性神经干细胞,可分化为神经元或神经胶质细胞,而rTMS可促进海马内源性神经干细胞向神经元的分化。     

大鼠脑缺血再灌注后海马CA1区AS与Syp相关性分析

目的研究大鼠脑组织缺血再灌注后星形胶质细胞与Syp变化的关系。方法建立局灶性脑缺血再灌注模型,72只大鼠随机分为假手术组、缺血再灌注组,各时间点处死取脑,应用免疫组化法检测海马CA1区GFAP、Syp的表达。结果不同时间点缺血再灌注组GFAP、Syp表达均高于同时期假手术组(P<0.01);缺血再灌注组GFAP与Syp高度相关(P<0.01)。结论脑缺血再灌注后,海马CA1区星形胶质细胞与Syp变化具有高度相关性。     

缺血后海马高迁移率族蛋白与星形胶质纤维酸蛋白表达及相关性

目的研究大鼠局灶性脑缺血再灌注星形胶质纤维酸蛋白(GFAP)与高迁移率族蛋白(HMGB1)在海马CA1区表达变化,探讨二者之间的关系。方法采用大脑中动脉栓塞2h制备SD大鼠脑缺血模型,60只雄性SD大鼠随机分为假手术组、缺血再灌注组,按1d、3d、7d、14d、28d时间点再分5个亚组,各时间点处死取脑,用免疫组化和荧光双标结合共聚焦扫描的方法来检测高迁移率族蛋白和星形胶质纤维酸蛋白在脑内海马CA1区表达变化。结果不同时间点缺血再灌注组GFAP、HMGB1表达均高于同时期的假手术组(P<0.05)。缺血再灌注组星形胶质细胞1d、3d、7d逐渐激活增生,7d达到高峰,14d开始下降;HMGB1在1d、3d、7d、14d是表达增加,14d达高峰,28d下降(与前一时间点比较P<0.05)。缺血再灌注组GFAP和HMGB1表达具有相关性(P<0.05),存在HMGB1和GFAP共定位细胞。结论脑缺血再灌注后,海马CA1区HMGB1增加与星形胶质细胞激活成正相关,过度表达的HMGB1和增殖的星形胶质细胞可能与缺血再灌注后神经元的迟发性损伤有关。     

STAT3在匹罗卡品致大鼠星形胶质细胞增生中的作用

目的探讨致状态下大鼠海马内信号转导与转录激活因子3(STAT3)与星形胶质细胞增生的关系。方法匹罗卡品(PILO)腹腔注射建立大鼠颞叶癫模型,免疫组织化学方法观察阻滞JAK/STAT通路前后大鼠海马p-STAT3与胶质纤维酸性蛋白(GFAP)阳性细胞的表达规律,双重免疫荧光方法观察p-STAT3与GFAP阳性细胞的关系。结果癫发作3h(SE3h)时即出现STAT3在海马内被激活,SE3d时达高峰,之后渐降低,至SE30d时仍维持在较正常时略高的水平上;GFAP阳性细胞数的变化规律与之类似。预先用AG490阻断STAT3通路后,海马区p-STAT3及GFAP阳性细胞数均明显减少。双重免疫荧光结果发现p-STAT3阳性胞核位于GFAP阳性细胞胞浆中。结论匹罗卡品导致的癫伴有大鼠海马星形胶质细胞内STAT3的激活,STAT3的活化可能促进星形胶质细胞的反应性增生。     

大鼠前脑缺血再灌注后GFAP、S-100表达的变化

目的 探讨胶质纤维酸性蛋白（GFAP）和S-100蛋白在大鼠前脑缺血再灌注后反应性星形胶质细胞的活化情况.方法 利用免疫组织化学方法检测前脑缺血再灌注模型的细胞活化情况.结果 脑缺血再灌注后第1d,顶叶皮层和海马可见少量GFAP阳性细胞表达 脑缺血再灌注第3d及第5d后GFAP阳性表达明显增加,并与对照组比较有统计学意义（P＜0.01）.S-100蛋白在脑缺血再灌注后第1d即有增加,并随着时间延长表达明显增强,各时间点与对照组有显著性差异（P＜0.01）.结论 脑缺血再灌注后GFAP、S-100蛋白表达增加,说明反应性星形胶质细胞的活化参与了脑缺血损伤后神经元的修复过程.     

STAT3在匹罗卡品致(癎)大鼠星形胶质细胞增生中的作用

目的 探讨致(癎)状态下大鼠海马内信号转导与转录激活因子3(STA3)与星形胶质细胞增生的关系.方法 匹罗卡品(PILO)腹腔注射建立大鼠颞叶癫(癎)模型,免疫组织化学方法观察阻滞JAK/STAT通路前后大鼠海马p-STAT3与胶质纤维酸性蛋白(GFAP)阳性细胞的表达规律,双重免疫荧光方法观察p-STAT3与GFAP阳性细胞的关系.结果 癫(癎)发作3 h(SE 3 h)时即出现STAT3在海马内被激活,SE 3 d时达高峰,之后渐降低,至SE 30 d时仍维持在较正常时略高的水平上;GFAP阳性细胞数的变化规律与之类似.预先用AG490阻断STAT3通路后,海马区p-STAT3乃及GFAP阳性细胞数均明显减少.双重免疫荧光结果发现p-STAT3阳性胞核位于GFAP阳性细胞胞浆中.结论 匹罗卡品导致的癫(癎)伴有大鼠海马星形胶质细胞内STAT3的激活,STAT3的活化可能促进星形胶质细胞的反应性增生.     

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.     

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.