Abstract
The bovine parotid glands were examined by transmission electron, scanning electron and light microscopies. The acinar lumina of the gland were notably spacious. Since the acinar cells were acidophil and reacted with periodic acid Schiff (PAS) but not stained with alcian blue (AB), they were thought to be serous in nature. The acinar epithelium was composed of light cells, dark cells and specific light cells. The light cells and dark cells contained various granules, many mitochondria and sparsely scattered RER short segments. The specific light cells had no granules along with few cytoplasmic organelles. The intercellular tissue spaces and canaliculi were well developed. The acinar cells extended many long microvilli into the lumina and into the intercellular spaces. The intercalated duct epithelium was composed of light cells alone, with no secretory granules. The striated duct epithelium also consisted of light cells, dark cells and specific light cells. These cells had no secretory granules. Their apical surfaces were characterized by the two different features, in that some were flat or folded and others had ovoidal or spheroidal protrusions of various sizes. In addition, between the epithelial cells of the striated duct and their basal lamina, there were special basal cells which had acidophil, PAS-positive and AB-negative granules with various electron densities.
