Léránth C, Frotscher M, Tömböl T, Palkovits M
Neuroscience. 1984 Jun;12(2):531-42. doi: 10.1016/0306-4522(84)90071-x.
In the hippocampus, antibody raised against vasoactive intestinal polypeptide (VIP) labeled perikarya and processes of non-pyramidal neurons whereas these structures remained unlabeled in pyramidal cells and granule cells. In the present study, VIP-immunostaining was used to investigate the fine structure and synaptic connections of identified non-pyramidal neurons and of immunoreactive axon terminals in the CA1 region of the rat hippocampus by means of electron microscopic immunocytochemistry. From a number of cells studied, two VIP-like immunoreactive non-pyramidal neurons in the regio superior were selected for an electron microscopic analysis of serial thin sections. These cells were different with regard to the location of their cell bodies and the orientation of their dendrites. One cell was located in the stratum lacunosum-moleculare with dendritic processes oriented parallel to the hippocampal fissure. The second neuron was found in the inner one-third of the stratum radiatum. The dendrites of this cell ran nearly parallel to the ascending apical dendrites of the pyramidal cells. Both cells had a round or ovoid perikaryon and an infolded nucleus. The aspinous dendrites of both neurons were densely covered with synaptic boutons. These terminals were small, filled with spherical vesicles, and established asymmetric synaptic contacts. No variations in the fine structure of the presynaptic boutons were found along the course of the labeled dendrites through the various hippocampal layers, although different afferents are known to terminate in these layers. Vasoactive intestinal polypeptide-like immunopositive axon terminals course through all layers of the hippocampus. In the stratum pyramidale they established symmetric synaptic contacts with the perikarya of pyramidal cells. In the stratum radiatum they made symmetric contacts with the shafts of apical dendrites of pyramidal cells but never contacted dendritic spines. The symmetric contacts with pyramidal cell perikarya suggest an involvement of the VIP-like immunoreactive axon terminals in pyramidal cell inhibition.
在海马体中，针对血管活性肠肽（VIP）产生的抗体标记了非锥体神经元的胞体和突起，而这些结构在锥体细胞和颗粒细胞中未被标记。在本研究中，通过电子显微镜免疫细胞化学方法，利用VIP免疫染色来研究大鼠海马体CA1区已鉴定的非锥体神经元和免疫反应性轴突终末的精细结构及突触连接。在所研究的众多细胞中，选择了上区的两个VIP样免疫反应性非锥体神经元进行连续超薄切片的电子显微镜分析。这些细胞在胞体位置和树突方向上有所不同。一个细胞位于分子层，其树突突起与海马裂平行。第二个神经元位于放射层内三分之一处。该细胞的树突几乎与锥体细胞的上升顶树突平行。两个细胞都有圆形或椭圆形的胞体和内陷的细胞核。两个神经元的无棘树突都密集地覆盖着突触小体。这些终末较小，充满球形囊泡，并形成不对称突触联系。沿着标记树突穿过不同海马层的过程中，未发现突触前小体的精细结构有变化，尽管已知不同的传入纤维在这些层终止。血管活性肠肽样免疫阳性轴突终末穿过海马体的所有层。在锥体层，它们与锥体细胞的胞体形成对称突触联系。在放射层，它们与锥体细胞顶树突的轴干形成对称联系，但从不接触树突棘。与锥体细胞胞体的对称联系表明，VIP样免疫反应性轴突终末参与了对锥体细胞的抑制作用。
