本研究采用两例犬心脏的窦房结,用冰冻切片——美兰染色,分离出结区的神经节,制备超薄切片,电镜观察。发现神经节细胞具有植物性神经元的特点。节细胞内除含有一般细胞器外,有些细胞的高尔基氏区还可见到大的颗粒小泡。卫星细胞伸出薄膜状突起包绕节细胞,二者间接触紧密。副交感神经的节前纤维多与节细胞突起接触并形成突触。节前纤维终末内除含有较多清亮小泡外,还含有少量大颗粒小泡。 In this study, we used two dogs’ canine sinoatrial node. Frozen section - Melanie staining was used to isolate the ganglia in the nodal area. Ultrathin sections were made and observed under electron microscope. Ganglion cells were found to have the characteristics of vegetative neurons. In addition to cells within the cell containing the general organelles, some cells in the Golgi area can also see large particle vesicles. Satellite cells extend film-like projections around the node cells, the contact between the two closely. Parasympathetic preganglionic fibers and synapses more contact with the synapses. Preganglionic fibers in addition to terminal fiber contains more clear, but also contains a small amount of large-sized vesicles.