一、窦房结细胞的形态学特征窦房结位于上腔静脉与右心房交界处心外膜下1～2mm处。Keith和Flack于本世纪初首先发现窦房结这一特殊心肌结构,后来得到电生理学研究工作以及光学显微镜和电子显微镜的研究结果所证实。窦房结细胞主要可区分为:P细胞(Pacemaker Cell),过渡型细胞(Transitional Cell)及浦肯野氏纤维。P细胞又称起搏细胞,常见成串、成簇地分布于窦房结内。细胞的外形呈圆型或椭圆形,直径甚小 First, the morphological characteristics of the sinus node cells Sinus node is located in the superior vena cava and right atrium at the junction of epicardial 1 ~ 2mm Department. Keith and Flack first discovered the special structure of the sinoatrial node in the beginning of this century, which was later confirmed by electrophysiological studies and optical and electron microscopy studies. Sinus node cells can be divided into: P cells (Pacemaker Cell), transitional cells (Transitional Cell) and Purkinje fibers. P cells, also known as pacemaker cells, common in clusters, distributed in the sinus node. The shape of the cell is round or oval, very small diameter