SYNAPTIC ULTRASTRUCTURE OF CAUDAL SPINAL TRIGEMINAL NUCLEUS IN RABBIT AND MOUSE

The caudal spinal trigeminal (CST) nucleus synapse consists of the pre- and postsynaptic mem branes and synaptic cleft. The active sites of the synapse consists of the presynaptic membranes. There are accumulated dense substances on the pre. and postsynaptic membranes, especially on the latter. Occasionally, subsynaptic cytoplasmic dense bodies ari: seen in the postsynaptic element, and intersynaptic filaments are found within the synaptic clefts. Synap- tic vesicles are located in the presynaptic terminals, Spherical, flat, granular and agranular synaptic vesi- cles are observed in presynaptic terminals. Numerous axon terminals, dendrites and axo dendritic, axosomatic, axoaxonic and dendrodendritic synapses were identified in the CST nucleus.. The dendrites were classified into type I (without synpatic vesicles) and type Il (few synaptic vesicles). Accord- iijg to the vesicle shape, the nuclear synapses are divided anto S (spherical), F (flat), S-F and F-S types. Anzong the observed synapses, about 20% were synaptic glomeruli. The functional significance of the synaptic pattem, glomeruli and vesicles in the CST nucleus are discussed.     

大鼠孤束核内含NT神经元的超微结构观察

用免疫电镜法对大鼠孤束核内侧亚核内NT-LI神经元的超微结构进行了观察。NT-LI产物可见于核周体、树突、轴突及终末内。标记轴突与树突构成轴-树突触最多见,轴-轴和轴-体突触少见。可见一些复合型突触和轴-树型自调节突触。此外一些NT-LI树突紧邻毛细血管。结果提示:(1)NT在孤束核调节心血管内脏活动中可能起着重要作用。(2)孤束核内NT神经元与血管之间可能存在神经-血管回路。     

人胎儿脊髓胶状质发育的电镜观察

用电镜观察１５～４０周人胎儿脊髓胶状质发育的超微结构变化。结果发现，胎儿胶状质神经元核大、核仁明显，胞浆薄、核搪体少；神经毡内无髓纤维最多，有髓纤维稀少。１５周可见有髓纤维，最宽径自１５至３２周增大明显，以后变化不大；１５至４０周髓鞘最厚处的厚度明显地增厚。２４周出现突触。发育中存在轴－树、轴－轴和树－树突触，以轴－树突触最多见。形成突触的轴突和树突各有两种类型。     

E_(18)胎鼠大脑皮质的电镜观察Ⅱ

本文对E_(18)胎鼠大脑皮质进行了电镜观察,发现分化幼稚的神经元缺乏突起,细胞核形态多样,与其它神经元之间无突触联系。分化较好的神经元可见有树突出现,且与其它神经元形成突触联系,并可见到中间型胶质细胞和神经元周卫星细胞。神经毡中可见到生长锥和有髓纤维。并对大脑皮质神经元和胶质细胞分化发育规律进行了探讨。     

皮质脊髓束谷氨酸能投射的定性追踪——光镜和电镜研究

用辣根过氧化物酶（ＨＲＰ）与免疫细胞化学结合和免疫电镜方法研究了大鼠皮质脊髓束的化学性质以及它们与脊髓神经细胞之间的超微结构关系。一侧脊髓背角或部分腹角注射ＨＲＰ后,光镜下在大鼠对侧大脑皮质第４区第Ⅳ层可见３种细胞：①谷氨酸（Ｇｌｕ）样免疫反应阳性细胞;②ＨＲＰ单标细胞;③ＨＲＰ和谷氨酸样免疫反应双标细胞。在大鼠脊髓腹角可见大量谷氨酸免疫反应阳性胞体和纤维。电镜下,在脊髓腹角内谷氨酸样免疫反应产物呈细小颗粒状沉淀,分布于树突、轴突、核周质以及星形胶质细胞内。此外,尚可见３种类型的突触：①Ｇｌｕ阴性轴突与Ｇｌｕ阳性树突构成的轴树突触;②Ｇｌｕ阳性轴突与Ｇｌｕ阴性树突构成的轴树突触;③Ｇｌｕ阳性轴突与Ｇｌｕ阴性轴突构成的轴轴突触。以上结果表明：大鼠皮质脊髓束至少有一部分纤维是谷氨酸能投射,这些纤维起自对侧大脑皮质,在脊髓内下行,主要终止于背角,部分终止于腹角,经中间神经元形成突触调控脊髓腹角细胞     

猴下橄榄核的超微结构

本文用透射电镜观察了猃猴下橄榄核的正常超微结构，结果表明：神经元的胞体多为中，小型圆形或梨形，胞核呈椭圆形或圆形，核膜常见凹陷，胞浆内细胞内较丰富。神经毡中以轴－树突触最常见。     

大鼠大脑皮质3,1,2区内胎脑皮质移植物超微结构观察

用 E_(15)胎脑皮质作供体,植入到中年 Wistar 大鼠大脑皮质的3,1,2区内。移植后120 d 的移植物电镜观察可见:移植物没有分层,大、小神经元形成细胞团簇。神经元、轴突发育正常,有的树突干走行倾斜,类似胶质细胞的突起。移植物神经毡中含各种类型的突触、突触小泡,而神经终末断面的大小较正常变化大。胶质细胞及其突起出现的频率比正常高。血管的分化与正常无异。本文并对上述现象出现的原因以及移植物中神经环路发育的规律进行了探讨。     

Morphological characteristics of the synaptic structures of substance P-immunoreactive terminals in the marginal division of the rat striatum

In the present study,the morphological characteristics of the synaptic structure(MCSS)of the substance P immunoreactive(SPIR)teminals in the marginal division(MrD)of the ratstriatum were studied by using electron microscopy and immunocytochemistry.Four major typesof SPIR symnapses were identified in teh MrD.axodendritic,axo-spinous,axo-axonic,and com-pound.Axo-dendritic and axo-spinous synapses were more common,and a few axo-axonic andcompound synapses wer observed as well.In the postsynaptic target zones of axo-dendritic,andaxo-spinous synapses,there were small or large dendrites or spires.Some synapses with morethan two synaptic components are referred to as compound synapses.Both symmetric andasymmetric SPIR synapses were seen in the MrD.The vesicles in the SPIR presynaptic boutonswere mostly pleomorphic although a few of them were round,The MCSS distinguishes theultrastructure of the MrD from that of the other part of striatum,which suggests that the func-tion of the MrD may be different from that of the rest of the striatum.     

Double Labeling Immulloelectron Microscopic Study on the Synaptic Connections between Glutamic Acid Neurons and GABA Neurons in the Hippocampus of Rats

The pathogenesis of epilepsy is a very complicated process, In which neurotransmltters play important roles. The hippocamplls is a frequently attacked site and an ideal model tissue for epilepsy' l]. In general, the seizure results from the imbalance of excitation and inhibition, i. e., increased effect of excltatory neurotransmltters ordecreased effect of inhlbitory neurotransrnlttersL =' ']. However, there was no nlorphologlcal, eel)eclally at the ultrastructural level, evidenceic identify …     

大鼠纹状体边缘区内P物质阳性终末的突触特征

本文用免疫电镜方法研究了大鼠纹状体边缘区内P物质阳性终末的突触特征。边缘区内可见4种P物质免疫反应阳性(SPIR)的突触,即轴树、轴棘、轴轴和复合突触。轴树和轴棘突触较常见,轴轴突触和复合突触较少。轴树和轴棘突触的突触后靶区为小或大的树突或棘,复合突触含两种以上突触成份。在边缘区内可观察到对称型和非对称型两种突触。SPIR突触前终扣内的小泡大部分是多形性的,很少为圆形。这些突触特征均和纹状体其它部位不同,提示边缘区内SPIR终末的来源可能和纹状体其它部位不同,同时也说明边缘区的功能可能和纹状体其它区不同。