Ultrastructure of von Ebner's salivary glands in the rabbit.

The von Ebner's salivary glands associated with the vallate and foliate papillae of the rabbit tongue were studied by light and electron microscopy. The glands are tubulo-alveolar in structure and have an abbreviated duct system. The seromucous cells of the secretory end-pieces contain numerous granules with a complex substructure; when the granule matrix is partially extracted as the result of less-than-optimal fixation, these granules are seen to contain bundles of 17-18 nm filaments. The ductular epithelium undergoes progressive change from simple columnar to stratified cuboidal or columnar. Both of these duct segments contain secretory granules that differ from those in the tubulo-alveolar cells and from each other. Thus the constituent cells of leporine von Ebner's glands produce a variety of organic secretory products.