大鼠海马移植物内神经元与CA能纤维之间突触联系的研究  

SYNAPTIC CONNECTIONS BETWEEN THE NEURONS AND CATECHOLAMINEGIC FIBRES IN THE HIPPOCAMPAL TRANSPLANT OF RAT

作　　者：蒋芝华[1] 吕建利[1] 曲富金 尹眉 黄世楷[1] 

机构地区：[1]中国科学院上海生理研究所

出　　处：《生理学报》1995年第3期281-286,共6页Acta Physiologica Sinica

基　　金：国家自然科学基金;国家科委中国科学院匹配经费(K.P85-2-10)资助

摘　　要：将胎龄为１７ｄ的大鼠胚胎海马（移植物）移植到同种成年大鼠（宿主）腹海马，９０ｄ后，用ＴＨ免疫细胞化学方法，对海马移植物内神经元与儿茶酚胺（ｃａｔｅｃｈｏｌａｍｉｎｅＣＡ）能纤维之间的突触联系进行了观察。免疫组织化学显示，宿主海马内有大量ＴＨ免疫反应纤维，这些纤维是直径为０．５—１μｕｍ的细纤维。它们的分布密度是，齿回门区和ＣＡ３区透明层内较密集，分子层次之，锥体细胞层和颗粒细胞层内较稀疏。在移植物的分子层和细胞层内，也有ＴＨ免疫反应纤维，它们略粗，有些纤维的直径大于１μｍ，纤维末端分支较多．免疫电镜的观察，在海马移植物内，看到许多ＴＨ免疫反应终扣与非免疫反应的树突棘和树突形成突触联系，这些突触主要是非对称型突触，突触间隙约３０ｎｍ左右，突触后膜明显增厚。以上结果表明：宿主脑内的ＣＡ能神经纤维可能是通过侧校长芽的形式，向移植物投射。投射到移植物内的ＣＡ能纤维，能同移植物内的神经细胞建立突触联系。The foetal hippocampal tissue (transplant) at 17th day of embryonic age was implanted into the ventral hippocampus of adult rats (host). The catecholaminergic fibre projections in the hippocampal transplants 90 days after operation were studied by immunohistochemical technique. It was observed that in the host hippocampus there was a large population of TH-immunoreactive slender fibres of only 0. 5-1μm in diameter. These fibres were distributed more densely in the hippocampal hilus and CA3 transparent layers than in molecular layers, but sparsely in pyramidal or granular layers.In the molecular and cellular layers of transplanted hippocampus some thicker (>1μm) TH-positive fibers were ended in a relatively dense branching. The immunoelectron-microscopic observations showed that many TH-positive boutons made synaptic contactS with immunonegative dendrites and dendritic spines in the hippocampal transplants, the majority of which were asymmetrical synapses with a 30 nm synaptic cleft and conspicuously thickened postsynaptic membranes. It is concluded that catecholaminergic fibres extend from the host brain into the hippocampal transplant to establish synapses with the forget neurons.

关 键 词：海马 移植物 儿茶酚胺能纤维 神经元 突触 

分 类 号：R338.26[医药卫生—人体生理学]