突触体素

突触体素（synaptophysin）是突触小泡膜上的一种含糖的膜结构蛋白。1985年，Jahn等[1]首先在大鼠脑中发现，因为它的分子量是38kD，所以Jahn等称之为P38。同年，德国肿瘤研究中心的Wieden－mann等o］在牛脑中也发现并且提纯了这种蛋白，把它命名为spoptophysin，周国民等［’］将之译为突触囊泡蛋白，吴偿等’‘增译为突触生长素，现在多译为突触体素。穷触体素一经发现，就曾引起人们的关注，一些学者应用识别突触体素的单克隆抗体SY38，在许多脊椎动物和非脊椎动物的中枢和周围神经系统的几乎所有被观察的神经终未内均发现有穷触体素…     

突触体素及癫痫发作后的突触重塑

突触体素(synaptophysin,SYN)是一种广泛存在于突触前囊泡膜上的钙结合糖蛋白,与突触的结构和功能密切相关。因其相对分子量为38KD,所以也简称为P38蛋白。1985年,Jahn等[1]和Wiedenmann等[2]先后在大鼠脑和牛脑内的突触前囊泡膜上发现此糖蛋白,命名为synaptophysin。研究表明,S     

突触体素免疫电镜染色法

突触密度是大脑结构和功能的重要参数,传统的方法借助电子显微镜通过测量突触末端的小平面来评价突触密度,其优点是能够直观得观测到突触,但是这种技术不仅费时,需要特殊的组织处理和设备,而且易受人工现象的干扰。突触体素(Synaptophysin,SYN)是所有突触小泡膜结合蛋白中含量最为丰富的一种特异性糖蛋白,它的发现为评价突触密度提供了新的方法。SYN存在于中枢神经系统的大多数甚至是全部的突触中,与突触小泡膜相结合,参与经典神经递质的释     

缺氧缺血性脑损伤新生大鼠海马突触体素的表达及当归调控作用

目的探讨脑缺氧缺血对新生大鼠海马齿状回突触体素表达的影响及当归注射对其表达的调控作用。方法取7日龄健康SD新生大鼠33只,随机分为对照组、缺氧组和当归组各11只。缺氧组和当归组新生大鼠在无菌环境下结扎左侧颈总动脉,术后护理2 h后置于三气培养箱持续缺氧2 h,制作新生鼠缺氧缺血性脑损伤（HIBD）模型,对照组仅行假手术,不结扎左侧颈总动脉、不缺氧。术后第8 d开始,缺氧组和对照组大鼠经腹腔注射生理盐水（8ml/kg）,连续7 d;当归组用等量当归注射液（250 g/L）代替生理盐水。于生后第22 d取大鼠脑组织,常规石蜡包埋、经海马切片,行突触体素（SY）免疫组化染色,图像分析海马齿状回SY阳性细胞的积分光密度（IOD）值。结果缺氧组大鼠海马齿状回SY阳性细胞的IOD值较对照组降低,而当归组SY阳性细胞的IOD值较缺氧组增高。结论脑缺氧缺血可降低新生大鼠海马齿状回SY的表达,而当归注射液对缺氧缺血性脑损伤新生大鼠可能具有保护作用。     

大鼠脑缺血后突触体素与突触密度的关系

目的：观察脑缺血后,大脑顶叶皮质突触体素的表达与突触密度的关系,为脑缺血后监测突触密度的变化提供了一个间接方法。方法：采用大鼠脑缺血模型,用免疫组化及电镜方法。结果：脑缺血后,随缺血时间的延长,突触体素的表达逐渐减少;神经毡内突触数目逐渐减少。结论：脑缺血后,随缺血时间延长,突触体素表达减少,神经毡内突触数目逐渐减少,二者之间呈正相关,说明突触体素可作为监测突触密度的间接指标。     

胎儿端脑突触素表达和突触发育的研究

为了探讨突触素(SYN)在不同周龄阶段胎儿端脑额叶中的表达与胎儿额叶皮质突触发育的关系,本研究采用免疫组织化学方法观察突触素在不同周龄阶段胎儿额叶的表达水平,利用计算机图像分析技术测量不同周龄阶段胎儿额叶突触素表达的平均光密度;同时取材、常规电镜技术处理、透射电镜观察额叶突触发育的超微结构变化。结果显示:(1)光镜下各组均可见SYN免疫阳性产物主要表达于胎儿的额叶皮层,其表达量随周龄的增加而增强,各组间呈现显著性差异(P<0.05),其中16～24周胎儿额叶的阳性产物位于神经元的胞浆内,呈均匀的浅黄色,神经元突起内未见阳性产物;25～29周额叶的阳性产物呈黄色,在胞浆和突起内均可见,但阳性产物的量却下降;而30～39周额叶的SYN阳性产物呈棕黄色的点状或颗粒状,主要位于神经元的突起内,神经元胞浆内未见阳性产物,阳性产物的量显著增加;(2)透射电镜下19～36周胎儿大脑额叶均可见到突触样结构,随着周龄的增加,突触的数量逐渐增多,结构逐渐清晰和完整。上述结果提示SYN的表达可以反映胎儿神经系统发育的程度,SYN的表达与突触的发育是一致的;SYN在胎儿大脑额叶的表达部位经历由神经元胞浆内表达为主到神经元终末表达为主的这一过程,可能是由于SYN先是在神经元胞浆内合成,再随着神经元的发育而逐步转移到神经元突起的末梢部位。     

突触体素、S一100蛋白和神经特异性烯醇化酶免疫反应神经纤维在人免疫器官的分布

目的探讨人免疫器官突触体素、S-100蛋白和神经特异性烯醇化酶(NSE)免疫反应神经纤维的支配和免疫反应细胞的分布,为神经内分泌和免疫系统相互作用提供形态学资料.方法应用免疫组织化学ABC法观察正常免疫器官包括胸腺、脾脏、淋巴结各30例.10%福尔马林固定,石蜡包埋.结果胸腺,突触体素、S-100蛋白和NSE免疫反应神经纤维从胸腺被膜随小叶间隔和血管到胸腺皮质,再延伸到髓质形成神经纤维网,在胸腺组织散在分布突触体素、S-100蛋白和NSE免疫反应细胞.淋巴结,免疫反应神经纤维沿被膜和门部结缔组织小梁及血管进入皮质后主要分布于副皮质区环绕淋巴滤泡,进一步分支到达髓质.在髓质髓窦内有NSE免疫反应细胞.脾脏,免疫反应神经纤维沿着血管的各级分支进入脾实质,主要沿着脾动脉的分支而分布在白髓、红髓和边缘区,穿插于淋巴细胞之间.结论在人免疫器官可能存在神经内分泌免疫系统相互作用和调控.     

局灶性脑缺血大鼠海马CA_3区突触体素动态表达

目的　研究局灶性脑缺血后海马CA3 区突触体素的动态表达以及神经修复的可塑性。方法　选取健康成年SD大鼠 4 0只 ,随机分为脑缺血组和对照组 ,每组又分为术后 7、14、2 1、30天 4个时间点 (n =5 )。采用线栓法建立大脑中动脉脑缺血大鼠模型 ,应用免疫组化技术观察海马CA3 区突触体素的表达。结果　脑缺血后各时间段突触体素阳性反应物表达的光密度较对照组明显降低 (P <0 .0 1) ;缺血后 7天至 2 1天突触体素表达逐渐回升 (P <0 .0 1) ,缺血后 30天又下降 ,但仍低于对照组。结论　突触体素可作为海马CA3 区神经元功能和损伤修复的标示物。     

抑郁小鼠模型脑突触体中突触蛋白表达的变化

目的:研究抑郁症发病过程中突触蛋白表达的变化。方法:小鼠随机分为对照组和造模组,使用社会失败模型对造模组小鼠造模,之后将其分为对抑郁症敏感组及对抑郁症不敏感组。将以上3组小鼠分别断头取前额叶皮层、海马、纹状体并提取突触小体,通过免疫印迹检测突触小体内突触后致密蛋白95(PSD-95)、桥尾蛋白(gephyrin)及突触蛋白1(synapsin-1)蛋白表达的变化。结果:与对照组相比,在前额叶皮层,对抑郁症敏感组及对抑郁症不敏感组小鼠的PSD-95水平下降,而对抑郁症敏感组小鼠的synapsin-1表达增多;在海马,对抑郁症敏感组及对抑郁症不敏感组小鼠的PSD-95水平下降;在纹状体,对抑郁症不敏感的小鼠gephyrin、synapsin-1蛋白表达显著增加。结论:在抑郁症发病中突触体内兴奋性及抑制性蛋白发生了变化,这些可能与突触功能的紊乱相关。     

金雀异黄酮对去卵巢大鼠海马突触体素表达的影响

目的：研究金雀异黄酮对去卵巢大鼠海马突触体素的影响,以探讨金雀异黄酮对女性更年期后中枢神经系统退行性变的作用机制。方法：用免疫组化结合图像分析的方法,测量分析去卵巢后不同时间点以及给予金雀异黄酮替代治疗后海马CA1～3区辐射层和齿状回分子层突触体素免疫阳性产物的平均光密度变化。结果：去卵巢后大鼠CA1～3区辐射层和DG分子层突触体素免疫阳性产物的平均光密度值逐渐降低,4周后与假手术组和苯甲酸雌二醇组相比有显著差异;金雀异黄酮组治疗后海马突触体素免疫阳性产物平均光密度恢复。结论：金雀异黄酮能恢复去卵巢大鼠海马突触密度,延缓女性更年期后中枢神经系统的退行性变。     

Synaptophysin in human breast carcinomas

Synaptophysin expression was studied immunohistochemically in 109 female and in three male breast carcinomas. Positivity was demonstrated in 10 female and in two male tumours in a high percentage of neoplastic cells. Synaptophysin positive breast carcinomas also expressed other neuroendocrine markers such as chromogranin and neuron-specific enolase.     

Synaptophysin expression abnormalities in Hirschsprung's disease

Hirschsprung's disease is defined by the congenital absence of ganglion cells in enteric plexuses. Immunostaining of synaptophysin after formalin fixation may be used to identify hyperplasia of nerve fibers and rarefaction of neuromuscular junctions in Hirschsprung's disease. The aim of the study was to evaluate semi-quantitatively the expression of synaptophysin in Hirschsprung's disease, in correlation with morphologic features. This retrospective study included 3 controls, 42 surgical rectal biopsies performed for suspicion of Hirschsprung's disease in children presenting with lower digestive occlusion or severe chronic constipation, including 18 Hirschsprung's disease, and 23 surgical specimens of Hirschsprung's disease. In the absence of Hirschsprung's disease, synaptophysin-positive fibers were numerous but thin in the muscularis mucosae, thin and scarce in the mucosa and submucosa. Neuromuscular junctions were thin and numerous in the muscularis propria. In Hirschsprung's disease, synaptophysin-positive fibers were coarse, and increased in number on each side of the muscularis mucosae. Plexuses were enlarged, weakly stained, and associated in the connective tissue of the muscularis propria with coarse and intensely stained fibers. In conclusion, staining for synaptophysin could be useful to demonstrate abnormalities of enteric innervation in rectal biopsies performed for suspected Hirschsprung's disease in the absence of acetylcholinesterase staining on frozen sections, in transmural biopsies performed for guiding surgery in Hirschsprung's disease, and in cases of extensive Hirschsprung's disease.     

突触体素与中枢神经系统突触发育

突触体素 (synaptophysin ,SYN)是一种分布很广的突触小泡膜蛋白 ,它在中枢神经系统的发育进程反映了一种时间与空间上的特殊表达模式。作为突触的标记物和突触密度的检测物 ,SYN对突触发育的研究具有实用价值。SYN与轴突及某些神经递质系统的发育关系密切 ,至于胆碱能纤维的发育与SYN表达的关系 ,有待深入研究     

Synaptophysin and neurofilament proteins as markers for neuroendocrine tumors

Synaptophysin, a membrane glycoprotein of presynaptic vesicles, and neurofilament (NF) proteins were tested as immunohistochemical markers for neuroendocrine tumors. Synaptophysin was consistently present in the tumor cells of pheochromocytomas (10/10), thyroid medullary carcinomas (8/8), and pancreatic islet cell tumors (6/6). Most gastrointestinal and thoracic carcinoid tumors (12/13) were positive, as were neuroendocrine carcinomas (7/9), of which two Merkel cell carcinomas were negative. The NF proteins were present in all pheochromocytomas, in three thoracic and one gastric carcinoid tumors, in four of eight thyroid medullary carcinomas, and in five of six pancreatic islet cell tumors. All intestinal carcinoids were negative for NF proteins, as were neuroendocrine carcinomas, except for two Merkel cell carcinomas that were positive. The 68-kilodalton (kd) NF subunit protein was the most prevalent in all NF-positive neuroendocrine tumors, and the 160-kd subunit was relatively often present, although in a smaller number of cells. The 200-kd NF subunit protein was regularly found in pheochromocytomas and only occasionally found in other neuroendocrine tumors. A series of nonneuroendocrine tumors, such as adenocarcinomas, sarcomas, lymphomas, and melanomas, were negative for both synaptophysin and NF proteins. Thus, synaptophysin is a specific and fairly sensitive marker for neuroendocrine tumors of both low and high grades of malignancy. The NF proteins are good markers for pheochromocytoma, and their presence is of basic tumor biologic interest and of potential diagnostic value in other neuroendocrine neoplasms.     

动脉自旋标记技术在脑部疾病中的临床应用

动脉自旋标记(ASL)技术是一种基于内源性对比剂的灌注功能磁共振成像技术,可以无损测量脑血流量(CBF)。与正电子发射断层摄影术(PET)、单光子发射计算机体层投影术(SPECT)、CT以及采用对比剂的磁共振灌注成像相比,ASL技术具有无损、简单易行、成本低等优点,适合长期随访研究。下面就当前ASL技术在诸如脑血管疾病、脑肿瘤、阿尔茨海默病以及癫痫等脑部疾病的临床应用进行综述。     

Synaptophysin: an immunohistochemical marker for animal dysautonomias

Equine and feline dysautonomias are characterized histopathologically by degenerating neurons with chromatolysis, pyknotic and sometimes eccentric nuclei, and loss of Nissl substance in the peripheral autonomic ganglia. Because it may be difficult to distinguish pathological from post-mortem changes in affected ganglia by histopathological examination, synaptophysin was evaluated as an immunohistochemical marker. Degenerating neurons showed strong intracytoplasmic labelling indicating abnormal accumulation of synaptophysin. It was concluded that synaptophysin immunohistochemistry is a helpful tool for detecting degenerating neurons in equine (grass sickness) and feline (Key-Gaskell syndrome) dysautonomias.