胎儿房室结的组织学和组织化学研究

利用光镜观察了２０例胎儿室房结、房室束和左、右束支的组织结构和组织化学特征。结果如下：１、胎儿房室结位于三尖瓣隔侧瓣上方，中心纤维体右侧。结石侧有普通心肌组成的覆盖层。房室结可分深浅两部。浅部纤维平行排列，垂直下行，止于结的下端。深部可分为上和下部。深部向后延伸与房间隔肌相连，向前延续为房室束。深部向右深入中心纤维体内形成许多细胞岛。２、房室束横断面大多为三角形，外包有疏松结缔组织鞘。房室束的前部

HlSTOLOGICAL AND HISTOCHEMICAL STUDIES OF ATRIOVENTRICULAR NODE IN FETUS

The histology and histochemistry of atnoventncular node (AVN). His's bundle and bundle branches in 20 fetuses were investigated under the light microscope. The results were as follows:1. The AVN was situated above the septal cusp of the tricuspid vahc and at the right surface of central fibrous bodylCFB). There were overlaying fibers, composed of cardiac muscles on the right surface of the AVN The AVN could be divided into superficial and deep parts. The former were longitudinal and ended in the lower border of the AVN The latter were subdivided into an upper and a lower part. The deep part attached to the muscle of the atnal septum posteriority and extended out as His s bundle in the front, and penetrated into CFB in the left to the processescalled archipelagos. 2. His's bundle surround by loose connective tissues, was mostly triangle in shape. The relations between His's bundle and the ventricular septal crest were 4 specimens on the left surface of interventricular septal crest, 3 on the right, 3 on the middle. 3. In the AVN, glycogen was strongly positive, 5'-Nase and SDH were weakly positive. AKP was weakly positive or negative, and ACP was strongly positive. According to the present studies, we discuss the morphological evidence of the delay, the longitudinal dissociation and the way of metabolism in the AVN in this paper.