大鼠胚心房肌细胞分化发育的超微结构研究

AN ULTRASTRUCTURAL STUDY OF THE DIFFERENTIATION AND DEVELOPMENT OF ATRIAL MUSCLE CELLS OF RAT EMBRYOS

本文在电子显微镜下,观察11~19天大鼠胚和新生大鼠心房肌的分化及发育,着重观察了心房特殊颗粒在鼠胚心房肌的发生和分布。胚11天时,未见心房肌细胞含特殊颗粒。12天时,少数心房肌出现特殊颗粒。随胚胎发育,这种颗粒在细胞内数量增加,体积变大。细胞分裂时,特殊颗粒不消失。第12天以后的鼠胚,在电镜下可区分含特殊颗粒和不含特殊颗粒的两种心房肌细胞,前者有较发达的高尔基复合体和粗面内质网。随胚胎发育,两种细胞的肌原纤维和线粒体均增多,渐趋成熟。

The development and differentiation of myocardial cells in the atria of rat embryos from 11 to 19 days and neonates were studied by electron microscopy,particularly with reference to the occurrence and distribution of atrial specific granules in muscle cells.The results were as follows:Atrial specific granules were invisible in muscle cells of 11 days embryos and occurred only in a few muscle cells in 12 days embryos.Since then their size and number in muscle cells increased with development.The granules persisted during mitosis.In atria of embryos from the 12th day on two kinds of myocardial cells could be distinguished,the one containing specific granules and the other without.The former showed well developed Golgi complex and abundant rough endoplasmic reticulum.As development proceeds both types of cells showed increasing amount of myofilaments and mitochondria in their cytoplasm and following the same trend approaching maturity.