title: Occurrence of unusual heterogeneous lipid-containing granule-storing cells in the main excretory duct epithelium of the male mouse submandibular gland.
abstract: The fine structure of the main excretory duct epithelium of the male mouse submandibular glands was investigated by scanning and transmission electron microscopy. Three principal cell-types were observed: type I and II, and basal cells. This epithelium was characterized by the presence of intercellular canaliculi. Type-I cells were the most numerous. They had an abundance of mitochondria, well-developed Golgi apparatus, a few electron-lucent lipid-containing granules and poorly developed basal infoldings. These cells were also characterized by many glycogen granules throughout the cytoplasm and abundant smooth endoplasmic reticulum in the apical cytoplasm. Type-II cells were the second most numerous. Their most characteristic feature was the presence of abundant heterogeneous lipid-containing granules having acid phosphatase activity at the periphery. They were concentrated in the infra- and supra-nuclear cytoplasm. The granules may be derived from mitochondrial transformation and seem to be a special kind of secondary autolysosome. Type-II cells also contained abundant mitochondria throughout the cytoplasm, much smooth endoplasmic reticulum in the apical cytoplasm, a well developed Golgi apparatus adjacent to the heterogeneous lipid-containing granules and no basal infoldings. Basal cells were situated adjacent to the basal lamina. They had a large nucleus and the cytoplasm was filled with glycogen granules.
authors.affiliation: First Department of Oral Anatomy, Fukuoka Dental College, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Sato
authors.forename: S
authors.initials: S
authors.lastname: Miyoshi
mesh_terms: D000135:Acid Phosphatase / Q000032:analysis; D000818:Animals; D003594:Cytoplasmic Granules / Q000737:chemistry* / Q000648:ultrastructure; D004847:Epithelial Cells; D004848:Epithelium / Q000737:chemistry; D008055:Lipids / Q000032:analysis*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D008928:Mitochondria / Q000648:ultrastructure; D013363:Submandibular Gland / Q000166:cytology*
chemical_list: D008055:Lipids; D000135:Acid Phosphatase