NF200在猫小脑中的分布及其老年性变化

目的探讨NF200（神经丝蛋白-200）在猫小脑中的分布及其老年性变化,以及导致相关变化的原因与在小脑功能衰老中的意义。方法利用Nissl染色显示小脑内部结构和神经元,免疫组织化学ABC法标记NF200免疫阳性（NF200-IR）结构。光镜下观察,采集图像,并利用Image-Pro Express5.1图像分析软件对小脑中NF200免疫阳性神经元以及各层免疫阳性反应灰度值进行分析统计。结果NF200免疫阳性神经元主要分布于蒲肯野细胞层和分子层底部,阳性纤维及终末在青年猫和老年猫小脑各层均有分布。与青年猫相比,老年猫蒲肯野细胞层神经元密度及其各层NF200免疫阳性反应强度均显著下降（P〈0.01）;蒲肯野细胞的胞体萎缩,阳性树突分枝明显减少。结论衰老过程中猫小脑NF200含量的下降,导致细胞结构紊乱,轴浆运输能力下降,可能是老年个体小脑功能衰退的重要原因之一。     

猫小脑皮质GABA能神经元年龄相关性变化

为探讨青年猫和老年猫小脑皮质GABA能神经元及其表达的年龄相关性变化,利用Nissl染色显示小脑皮质结构及神经元,免疫组织化学ABC法标记GABA免疫阳性神经元。光镜下观察,采集图像,并利用图像分析软件对分子层、蒲肯野细胞层和颗粒层神经元及GABA免疫阳性神经元及其灰度值进行分析统计。结果显示,GABA免疫阳性神经元、阳性纤维及终末在青年猫和老年猫小脑皮质各层均有分布。与青年猫相比,老年猫分子层、蒲肯野细胞层神经元和GABA免疫阳性神经元密度及其GABA免疫阳性反应强度均显著下降(P<0.01),颗粒层神经元密度和GABA免疫阳性强度也显著下降(P<0.01),但其GABA免疫阳性神经元密度无显著变化(P>0.05);蒲肯野细胞的胞体萎缩,阳性树突分枝减少。因此认为,衰老过程中猫小脑皮质GABA能神经元的丢失和GABA表达的下降,可能是老年个体运动协调、精确调速和运动学习等能力下降的重要原因之一。     

GDNF在慢性应激和老化致小鼠行为与认知损伤中的作用

目的:探讨慢性应激对不同月龄小鼠空间学习记忆功能的影响,以及小鼠前脑皮层和海马胶质细胞源性神经营养因子(GDNF)的作用。方法:采用多因素慢性应激动物模型,通过旷场试验和Morris水迷宫试验,检测不同月龄小鼠行为及空间学习记忆能力,并检测GDNF在小鼠脑海马和前脑皮层的表达。结果:与青年(2月龄)小鼠比较,老年(15月龄)小鼠的自发活动和探究行为明显减少,空间学习记忆能力明显降低(P<0.05,P<0.01),且海马CA3区、齿状回和前脑皮层GDNF表达明显下降(P<0.05,P<0.01);在慢性应激后,与对照组比较,青年和老年应激组小鼠的自发活动和探究行为显著减少,空间学习记忆能力显著降低(P<0.05,P<0.01),且小鼠前脑皮层和海马GDNF表达显著下降(P<0.05,P<0.01),老年应激小鼠变化更加显著。结论:脑的老化和慢性应激导致小鼠行为及空间学习记忆功能改变,可能与海马和前脑皮层神经元GDNF表达的变化密切相关。     

树突棘素在大鼠小脑中的表达和年龄变化

目的 观察树突棘素在大鼠小脑中的表达及年龄相关性变化。方法 应用免疫组织化学和Western blot方法,显示树突棘素在不同年龄组的大鼠小脑中的表达,并用图像分析系统对阳性免疫反应结果进行定量分析。结果 在中年组大鼠小脑中,树突棘素呈高表达,而在老年组和青年组大鼠小脑组织中表达水平相对较低。在小脑树突棘素的表达以分子层为主,其次表达在颗粒层细胞周围,少量树突棘素在大鼠小脑的蒲肯野细胞也有表达。结论 树突棘素的表达随着年龄的改变而变化;这种变化可能与不同年龄段大鼠小脑组织中突触的可塑性变化有关。     

δ-Catenin在大鼠小脑的表达及其年龄差异

目的探讨-δcatenin在不同年龄大鼠小脑的表达特征及年龄差别。方法应用免疫组织化学方法检测δ-catenin在小脑的定位表达,并用图像分析系统和免疫印迹(Western-blot)进行定量分析。结果免疫组化显示-δcatenin在中年大鼠小脑表达最高。在老年大鼠小脑表达最低。结果具有统计学差异。结论-δcatenin在大鼠小脑的表达存在增龄性变化。这一变化和不同年龄大鼠小脑突触的数量,结构和功能的变化有关。     

大鼠脑内caveolin-1蛋白的表达及其在分辨学习中的作用

Caveolin-1（Cav—1）蛋白作为细胞质膜结构小窝（caveolae）的标志蛋白,在胆固醇运输、膜组装、信号转导和细胞转化过程中扮演重要的角色。为了探讨Cav-1蛋白在中枢神经系统可塑性及学习记忆中的作用,本文以Sprague—Dawley大鼠为实验对象,利用蛋白质免疫印迹杂交方法观察了Car-1蛋白在不同年龄大鼠脑内表达的特征,并研究了Y-迷宫训练前后Cav-1蛋白表达的变化。结果表明：（1）大鼠不同脑区Cav-1蛋白表达的年龄特征不同。海马内的表达属青年鼠最高,其次是老年鼠和幼年鼠;皮层内的表达属幼年鼠最高,其次是老年鼠,青年鼠最低;小脑内的表达无明显年龄差异。（2）Y-迷宫训练引起青年鼠海马和前额叶皮层内Cav-1蛋白的表达显著增加。结果提示,Cav-1蛋白与动物脑发育和学习记忆有密切关系,可能参与中枢可塑性的调节。     

猫小脑髓质胶质反应的年龄相关性变化

探讨青年猫和老年猫小脑髓质中胶质反应的年龄相关性变化及其意义。用改良的Holzer结晶紫染色显示所有胶质细胞,GFAP(胶质纤维酸性蛋白)免疫染色显示星形胶质细胞。光镜下对青年猫与老年猫小脑髓质中胶质细胞和GFAP免疫阳性(GFAP-IR)星形胶质细胞进行形态学观察和定量研究。与青年猫比较,老年猫小脑髓质中胶质细胞和GFAP-IR细胞密度均显著增加(P<0.01),胞体较大;GFAP阳性细胞阳性反应较强,突起稠密;星形胶质细胞占胶质细胞总数比例增加。这表明小脑髓质中胶质细胞随年龄增长明显增生,尤其星形胶质细胞具有明显的年龄相关性活动增强。提示胶质细胞及星形胶质细胞的增生可能对衰老的神经纤维起保护作用;星形胶质细胞对衰老较敏感。     

Adam10基因在成年小鼠中枢神经系统的表达模式研究

目的研究adam10基因在成年小鼠中枢神经系统表达的脑区分布特点以及细胞类型。方法构建小鼠源性adam10 cRNA探针,通过原位杂交技术,观察adam10 mRNA在成年小鼠中枢神经系统分布特点,并在原位杂交后进行免疫组织化学染色,把adam10原位杂交信号和神经元、星形胶质细胞特异性细胞标记物进行双标,观察adam10基因表达的细胞类型。结果 Adam10基因在成年小鼠大脑皮层、海马、丘脑和小脑中表达,原位杂交后进行免疫组织化学染色结果显示adam10原位杂交阳性信号主要和神经元标记物NeuN共标,而和星形胶质细胞标记物GFAP不共标。结论本研究证实了在成年小鼠中枢神经系统中adam10基因在大脑皮层、海马、丘脑和小脑中都有表达;并且首次明确了大脑中ad-am10基因主要在神经元中表达,在星形胶质细胞中不表达,小脑中主要在小脑颗粒细胞和蒲肯野细胞中表达。     

人体小脑神经元发育的定量观察

目的：研究人体小脑神经元的发育过程。方法：应用体视学方法,对18例不同时期人体小脑组织Golgi染色后进行观察,观测小脑皮质分层出现的时间,观测并计算神经元的数密度、体密度和表面积密度。结果：6月龄时,小脑皮质出现较明显的分子层、蒲肯野细胞层和颗粒层;星形细胞、篮状细胞、蒲肯野细胞、颗粒细胞和高尔基细胞的的数密度随月龄／年龄的增长而减少,体密度和表面积密度随月龄／年龄的增长而增加,但这些减小和增大是不等速的,6-8月龄变化最明显。结论：人体小脑神经元的发育呈现快慢交替、不均速发展,6～8月是小脑神经元发育的重要时期。     

人体小脑神经元发育的定量观察

目的:研究人体小脑神经元的发育过程。方法:应用体视学方法,对18例不同时期人体小脑组织Golgi染色后进行观察,观测小脑皮质分层出现的时间,观测并计算神经元的数密度、体密度和表面积密度。结果:6月龄时,小脑皮质出现较明显的分子层、蒲肯野细胞层和颗粒层;星形细胞、篮状细胞、蒲肯野细胞、颗粒细胞和高尔基细胞的的数密度随月龄/年龄的增长而减少,体密度和表面积密度随月龄/年龄的增长而增加,但这些减小和增大是不等速的,6-8月龄变化最明显。结论:人体小脑神经元的发育呈现快慢交替、不均速发展,6～8月是小脑神经元发育的重要时期。     

HSP70 constitutive expression in rat central nervous system from postnatal development to maturity.

We studied the level of the basal (constitutive) HSP70 expression (inducible and constitutive forms) in the central nervous system (CNS) of male and female rats from the postnatal period to maturity. HSP70 levels were analyzed by immunoblotting in five different areas (cortex, hippocampus, hypothalamus, cerebellum, and spinal cord). The highest levels of HSP70 were found in juvenile rats and decreased progressively until reaching baseline levels between 2 and 4 months. A slight and nonsignificant increase in aged (2-year-old) rats compared with adult subjects was observed in some cerebral areas (cerebral cortex, hippocampus, and cerebellum). In the first weeks of postnatal development, HSP70 immunoreactivity was distributed throughout CNS sections and no specific immunopositive cells could be clearly determined. In adult animals, strong immunostaining was observed in some large neurons (Purkinje neurons and mesencephalic and spinal cord motor neurons), some perivascular and subpial astrocytes, and ependymocytes. Immunoelectron microscopy revealed that HSP70 in these cells is located in the perinuclear area and in mitochondria, rough endoplasmic reticulum, and microtubules. In neurons, strong immunolabeling was also observed in synaptic membranes. The postnatal time course of HSP70 levels and the location and size of HSP70-immunopositive cells suggest that HSP70 constitutively expressed in the rat CNS may be mainly determined by the degree of development and metabolic activity of the neural cells.     

鞘内注射M受体和GDNF反义寡脱氧核苷酸抑制吗啡戒断大鼠蓝斑c-Fos表达

应用免疫组化方法观察鞘内注射毒蕈碱型乙酰胆碱(muscarinic acetylcholine receptor,M) 受体和胶质细胞源性神经营养因子(glial cell derived neurotrophic factor,GDNF)反义寡脱氧核苷酸对吗啡戒断大鼠蓝斑(locus coeruleus,LC)区内Fos表达的影响。结果显示,鞘内注射M_2受体和GDNF反义寡脱氧核苷酸明显减少大鼠吗啡戒断症状评分值(n=6,P<0.05)。正常大鼠LC区神经元Fos基础表达较低,吗啡依赖大鼠LC区神经元Fos表达增加,吗啡依赖大鼠纳酪酮(4mg/Kg,ip)催促戒断后,Fos表达进一步增加;鞘内注射M_2受体和GDNF反义寡脱氧核苷酸处理后均减少吗啡戒断大鼠LC区神经元Fos表达(n=5,P<0.05)。而鞘内注射M_1受体反义寡脱氧核苷酸处理组LC 区神经元Fos表达较吗啡戒断组没有显著差异(n=5,P>O.05)。结果提示:脊髓M_2受体调节吗啡戒断时LC区的神经元激活,而这种神经上行性激活涉及神经元与胶质细胞之间的适应性调节。     

Expression of alpha-synuclein in different brain parts of adult and aged rats.

The synucleins are a family of presynaptic proteins that are abundant in neurons and include alpha-, beta, and gamma-synuclein. Alpha-synuclein (ASN) is involved in several neurodegenerative age-related disorders but its relevance in physiological aging is unknown. In the present study we investigated the expression of ASN mRNA and protein in the different brain parts of the adult (4-month-old) and aged (24-month-old) rats by using RT-PCR technique and Western blot, respectively. Our results indicated that mRNA expression and immunoreactivity of ASN is similar in brain cortex, hippocampus and striatum but markedly lower in cerebellum comparing to the other brain parts. Aging lowers ASN mRNA expression in striatum and cerebellum by about 40%. The immunoreactivity of ASN in synaptic plasma membranes (SPM) from aged brain cortex, hippocampus and cerebellum is significantly lower comparing to adult by 39%, 24% and 65%, respectively. Beta-synuclein (BSN) was not changed in aged brain comparing to adult. Age-related alteration of ASN may affect the nerve terminals structure and function.     

bFGF对脑缺血再灌注大鼠海马及顶叶皮质神经元的保护作用

目的本实验应用大脑中动脉栓塞（MCAO）模型,观察bFGF对脑缺血再灌注损伤后海马及顶叶皮质中Wnt通路抑制因子Dickkopf-1（DKK-1）和Wnt通路中pCatenin的表达作用的影响,以探讨Wnt通路对缺血性脑损伤的作用机制,为临床治疗缺血性脑血管病提供实验依据。方法应用线栓法制作大鼠局灶性脑缺血再灌注模型,大脑中动脉阻塞1h再灌注损伤24h,采用免疫组织化学SABC法及RT-PCR法检测海马及顶叶皮质CA1区神经元β-Catenin和DKK-1mRNA的表达。结果正常sham组,大鼠海马组织DKK-1 mRNA表达较少,β-Catenin阳性产物在细胞质内有所表达;I／R组,DKK-1 mRNA表达明显增多,β-Catenin在胞质内表达明显减少;bFGF组,大鼠海马组织DKK-1 mRNA表达较I／R组明显减少,而海马细胞质内β-Catenin表达较I／R组明显增加。结论bFGF抑制缺血神经元凋亡,参与DKK-1 mRNA和β-Catenin的调节,对缺血神经元有保护作用。     

AGRIN在老年鼠大脑皮质和海马的表达

目的观察蛋白聚糖-agrin在大鼠大脑皮质和海马的表达,探讨agrin与记忆的关系.方法用抗agrin的多克隆抗体,免疫组化方法检测成年大鼠、记忆正常老年鼠以及记忆障碍的老年鼠大脑皮质和海马中agrin的表达变化.结果 Agrin在不同动物组的表达变化明显,在成年鼠和记忆正常的老年鼠的大脑皮质和海马agrin有较弱表达,但在记忆障碍的老年鼠其表达增加明显.结论 Agrin表达可能和大鼠的记忆障碍有关.     

猫腰髓中GABA能神经元的分布及年龄相关变化

目的观察和比较GABA能神经元在青年猫和老年猫L6段脊髓的分布,探讨GABA能神经元在脊髓中分布的年龄相关变化及意义.方法免疫组织化学ABC法.结果青年猫与老年猫L6段脊髓灰质内,GABA能神经元及神经纤维分布广泛,各个Rexed板层均可见GABA-IR细胞,其中背侧灰质阳性最强,其次是腹侧灰质.标记的GABA能神经元胞体为卵圆形、三角形、多角形和星形,可分为大、中、小三种类型.经比较,老年组GABA能神经元的数量及免疫反应性均明显低于青年组.结论老年动物脊髓调节功能的减弱可能与GABA能神经元减少有少.     

Effect of Acute Stress on Hippocampal Glutamate Levels and Spectrin Proteolysis in Young and Aged Rats

Abstract: Aging in rats is associated with a loss of hippocampal neurons, which may contribute to age-related cognitive deficits. Several lines of evidence suggest that stress and glucocorticoids may contribute to age-related declines in hippocampal neuronal number. Excitatory amino acids (EAAs) have been implicated in the glucocorticoid endangerment and stress-induced morphological changes of hippocampal neurons of young rats. Previously, we have reported that acute immobilization stress can increase extracellular concentrations of the endogenous excitatory amino acid, glutamate, in the hippocampus. The present study examined the effect of an acute bout of immobilization stress on glutamate levels in the hippocampus and medial prefrontal cortex of young (3–4-month) and aged (22–24-month) Fischer 344 rats. In addition, the effect of stress on spectrin proteolysis in these two brain regions was also examined. Spectrin is a cytoskeleton protein that contributes to neuronal integrity and proteolysis of this protein has been proposed as an important component of EAA-induced neuronal death. There was no difference in basal glutamate levels between young and old rats in the hippocampus or medial prefrontal cortex. During the period of restraint stress a modest increase in glutamate levels in the hippocampus of young and aged rats was observed. After the termination of the stress procedure, hippocampal glutamate concentrations continued to rise in the aged rats, reaching a level approximately five times higher than the young rats, and remained elevated for at least 2 h after the termination of the stress. A similar pattern was also observed in the medial prefrontal cortex with an augmented post-stress-induced glutamate response observed in the aged rats. There was no increase in spectrin proteolysis in the hippocampus or medial prefrontal cortex of young or aged rats after stress or under basal nonstress conditions. The enhanced poststress glutamate response in the aged rats may contribute to the increased sensitivity of aged rats to neurotoxic insults.     

蝎毒对癫痫大鼠海马内强啡肽原mRNA表达的影响

目的和方法：本工作用红藻氨酸癫痫模型,通过对癫痫大鼠蝎毒处理后民内哟啡肽原ｍＲＮＡ（ＫＰＵＹＮｍＲＮＡ）表达的原位杂交观察,对国产蝎粗毒抗癫痫反复发作的细胞分子机制进行初步探讨。结果：原位杂交的实验显示,三周ＫＡ后,实验对照组与空白对照组相比,腹侧海马尤其是海马门区ＰＤＹＮｍＲＮＡ阳性数目明显减少（Ｐ〈０．０１）。实验给药组大鼠８例,其中有６例腹侧海马门区ＰＤＹＮｍＲＮＡ阳性神经元数目未见减少且有