Electron microscopic investigations on the differentiation of Purkinje cells in the ontogenetic development of the chicken heart

摘要

The ultrastructural development of subendocardial Purkinje cells of chicken left ventricle was investigated. In 9-day-old chick embryos the cell diameter and the organization of the cell organelles allow a distinction between Purkinje cells and ordinary myocardial cells. In 14-day-old chick embryos, Purkinje cells show large accumulations of myosin filaments with interspersed ribosomes in addition to normomeric myofibrils. In these accumulations actin filaments seem to be absent. The deficiency of actin filaments is supposedly the reason for the random distribution of the myosin filaments.