摘要
用透射电镜技术观察了大鼠伏核,伏核内的神经元多为小圆形和椭圆形,外形较规则,直径在10～15μm之间。核为椭圆形,有时可见核膜内陷。核质比例大。胞质中可见多种细胞器。大部分胞体的外表面均可见以对称型为主的轴-体突触。轴-体突触约占伏核内突触总数的2％。树突的外形和行径一般较规则,较粗大的树突多与轴突终末形成对称型的轴-树突触,而细树突多构成非对称型的轴-树突触。可见顶端稍膨大的细长形树突棘,棘多与轴突终末形成非对称型的轴-树棘突触。轴-树突触约占97％。轴突多较细,行径也直。它们在近终端处常形成被透明圆形小泡所充满的局部膨大,并在此处与树突形成路过性突触。神经毯内常见2个或2个以上的轴突终末聚集在一起,仅有少数形成对称型的轴-轴突触,另可见轴-轴-树突触复合体。轴-轴突触约占0.5％。上述突触的突触前成分主要含透明圆形小泡,有时有少量扁平形小泡、椭圆形小泡和颗粒囊泡混杂其间,少数突触以扁平形小泡为主。
The submicroscopic structure of nucleus accumbens (Acb) was observed under transmission electron micrscope in the present study. Most of the Acb neurons were spherical, with diameter ranging from 10 μm to 15 μm. The nucleus were ellipsoid with, sometimes, nucleolus and deep invaginations of nuclear membrane. The nucleocytoplasmic ratio was always rather high. Axo-somatic synapses were formed on the surface of most neuronal perikarya, predominantly of the symmetric type. The percentage of axo-somatic synapses in total number of Acb synapses was 2%. Generally, the outline of the dendrites was regular. Most of the thick dendrites made symmetric axo-dendritic synapses while the thin dendrites usually made asymmetric axo-dendritic synapses. Some of the irregular dendrites had spines. The spines were usually long and thin, with enlarged end and markedly thin neck, and formed asymmetric synapses with axonal terminals. The axo-dendritic synapes composed 97% of the total synapses within Acb. Small sized axons were frequently observed. The majority of the axon terminal segments contained clear round vesicles and made synapses en passant with the dendrites. Synapses en passant were also observed on the collaterals of axon. Two or more axonal terminals were often closely contacted, but no typical synaptic formations were found. Only a few axo-axonic synapses could be observed. Axoaxonic-dendritic synaptic complexes were also seen. The percentage of axo-axonic synapse was 0.5%. Most of the synaptic boutons mentioned above were mainly filled by spherical vesicles, some of them were filled with pleomorphic vesicles.
出处
《解剖学报》
CAS
CSCD
北大核心
1992年第3期264-267,共4页
Acta Anatomica Sinica
关键词
伏核
亚显微结构
大鼠
Nucleus accumbens
Submicroscopic structure
Rat
