Abstract
Scanning electron microscopic study of bronchial glands was carried out. Bronchial tissues from resected lung lobes without bronchial diseases and those with bronchiectatic materials were used. Bronchial glands of cats were also studied. In cases of cats and humans without bronchial diseases, the openings of the glands on the bronchial mucous membrane were usually oval in shape and several ten microus in diameter. The distance between each of them was several hundred microus to 1mm. Diverticula about several hundred microus to 1mm in diameter were found in some bronchial mucous membranes and some openings of the glands were observed at their walls or lower portions.
Ciliated ducts, collecting ducts, mucous tubules, and serous tubules were observed on the fracture surface of bronchial tissues. The luminal surface of ciliated ducts was covered with abundant cilia. On the surface of collecting ducts, short microvilli and polygonal partitions of epithelial cells could be observed. Round openings of secretory tubules with secretory products were scattered on the surface.
Profuse granules were found in the cytoplasm of secretory cells. The granules of serous cells were well demarcated and those of mucous cells had a tendency to be confluent. Scanty microvilli and a few small openings through which secretory substances might have been discharged were observed on the surface of secretory cells.
In the case of bronchiectasis, nonciliated areas were observed around the openings of bronchial glands. In ciliated ducts, hyperplasia of goblet cells was observed. Marked alterations were found in the collecting ducts, and secretory tubules. The top of each of the epithelial cells lining these ducts and tubules showed prominent protrusions toward the lumen. The cells of collecting ducts contained abundant granules about 0.8 micra in diameter in their cytoplasm. These findings might suggest these cells to be accelerated functionally.
