Innervation of the mucosa of rabbit maxillary sinus. I. Electron microscopic findings

The terminal nerve plexus in all parts of the rabbit maxillary sinus was studied at the electron microscopic level. Intra-epithelial varicosities could be observed in close connection to all types of epithelial cells in the respiratory ciliated epithelium as well as in the glandular epithelium. Following intercellular spaces the predominantly basal varicosities may even reach layers near the epithelial surface. Nerve profiles deeply invaginated into epithelial cells are considered to represent a very intensive nervous transmission. The functional significance of the terminal nerve plexus is discussed.