Ultrastructural Study of the Alveolar Brush Cell

Abstract

The surface morphology of alveolar brush cells in rats of the Wistar strain was studied using a transmission, and especially, a scanning electron microscope. The alveolar brush cells have about 120–140 microvilli, 0.9–1.2 μm in length and 0.2 μm in diameter, on their surface. These cells were spherical in shape and much taller than Type IE cells. Three dimensional observations clearly indicated that the alveolar brush cells were not situated within the respiratory bronchiole. In each microvillus, there are about 170 fine filaments which extend deeply into the cytoplasm without ending in the terminal web. An increased population of alveolar brush cells was observed in rats with Bleomy-cin induced interstitial pneumonia. Morphological characteristics of the alveolar brush cells suggest that they have some chemoreceptive function.