Scanning electron microscopy of bronchiolar neuroepithelial bodies in neonatal mouse lungs.

Scanning electron microscopy of the bronchiolar neuroepithelial bodies (NEB's) in the neonatal mouse lungs was undertaken and correlated with the accompanying transmission electron microscopy. The NEB's appeared as isolated organoids along the entire length of the bronchioles, and often were located at the branching points. The boundary of the NEB's was outlined by the ciliated and Clara cells. Both granulated cells and modified Clara cells participated in the formation of the NEB. The modified Clara cells covered most of the surface of the NEB leaving only small oval areas for the exposed surfaces of the specialized cells which contained numerous cytoplasmic granules. Short and regular microvilli projected from the exposed surfaces of the granulated cells, while only sparse microvilli of irregular length were seen on the surfaces of the modified Clara cells. This scanning electron microscopy of the NEB's further established these organoids as separate morphological entities. In addition, the findings that the NEB's could be easily identified with the scanning electron microscope and subsequently dissected out for further studies would help future investigations of their functions which are not clearly known.