THE STRUCTURE OF THE BRONCHO-ALVEOLAR SYSTEM WITH SPECIAL REFERENCE TO ITS FINE STRUCTURE

Abstract

1) In the bronchial epithelium, three types of cell are revealed by electron microscopy, namely, ciliated cell, goblet cell and basal cell. 2) The alveolar wall is found to be covered continuously with two kinds of epithelial cells, namely, alveolar epithelial cell and alveolar wall cell. 3) There seem to be two types of dust cells, one of which originate from alveolar wall cell and the other from monocyte. 4) Non-specific inflammation against foreign bodies or bacteria sets in as exudation of cells into the alveolar space. 5) Some cells similar to bronchial epithelial cell and alveolar wall cell are involved in the same tumor induced by urethane. 6) In the tumor that is considered to be of bronchial origin, some cells similar to the alveolar wall cell can be found.