狗窦房结形态的光镜观察

利用显微镜观察了23例狗心窦房结的连续切片。窦房结位于腔耳连结处(腔耳角)下方,界沟静脉窦侧的心外膜下,其长轴与界沟一致。窦房结为上部宽下部变细的长梭形,中心区位于上1/3与中1/3交界处,大小为11.06×2.95×1.16mm。窦房结动脉穿结实质者仅6例,其余者可在结的静脉窦侧、心房侧或深部的心肌内。构成窦房结的主要细胞有P细胞和T细胞。P细胞圆形、较小、核大、淡染,成团主要存在于结的中央。T细胞形态界于P细胞和心房肌细胞之间,主要位于结的周边。结内有大量胶元纤维。神经纤维和节细胞在结下部丰富。

LIGHT MICROSCOPIC OBSERVATION ON THE SINO-ATRIAL NODE OF THE DOG

The sino-atrial node was observed in 23 dog hearts with serial slices. The sino-atrial node lies below auriculocaval junction, beneath the epicardium of sinus venosus by the side of the sulcus terminalis. The shape of the sino-atrial node is a long spindle with a greater upper part and a thiner lower part. Its central area is located near the junction of upper 1/3 and middle 1/3. Its size is 11.06×2.95×1.16mm, The sinoatrial node artery penetrates through the sino-atrial node only in 6 cases. In others, it may be located in sinus venosus side, the atrial side of the node or in the deep myocarium. Within the sino-atrial node there are chiefly P-cell ane T-cells. The P cell is small with greater nuclear, light colored, and formes clusters which present themselves in the centre of the sino-atrial node. The size of the T cell is between P cell and the myocardial working cell and is situated on the peripery of the sino-atrial node. In the sino-atrial node there are large numbers of collagen fibers. The nerve fiber ls appear more abundant near the lower part of the sino-atrial node.