ULTRASTRUCTURE OF THE DEEP POSTERIOR LINGUAL GLANDS (VON EBNER'S) IN THE ONE-HUMPED CAMEL (CAMELUS DROMEDARIUS)

SUMMARY Camel deep posterior lingual glands (von Ebner's glands) were studied by light and transmission electron microscope. They were located beneath the circumvallate papillae. These glands were formed of tubuloalveolar secretory units and an excretory system. Intense PAS reactivity and slight alcinophilia were demonstrated only in the secretory cells as well as in few intercalated duct cells. The seromucous secretory cells lacked basal folds and characterized by numerous secretory granules, that consisted of electron dense core of fine fibrillar material surrounded by electron lucent marginal zone containing fine strands. These cells contained also numerous mitochondria, some of them of unusual shapes, well developed Golgi-apparatus and abundant RER cisternae stacked at the basal pole. In addition, numerous ribosomes, cytoplasmic filaments, microtubules and few lipid droplets were observed. The excretory system was organized in intercalated ducts, excretory ducts and main duct. The transition between the glandular portions and the intercalated ducts was gradual. The intercalated ducts show similarities with the analogous ducts of the other salivary glands. The striated ducts were absent. Myoepithelial cells had the common criteria of contractile elements. Unusual forms of their relations to the secretory end pieces and intercalated ducts were observed. The morphology of the von Ebner's glands of camel was compared with the analogous glands of other species and with other major salivary glands.