A scanning electron microscope study of myoepithelial cells in the intercalated ducts of rat parotid and exorbital lacrimal glands.

Myoepithelial cells in the intercalated ducts of rat parotid and exorbital lacrimal glands were examined by scanning electron microscopy. The basal surface of the intercalated ducts revealed myoepithelial cells running parallel with its long axis. These myoepithelial cells were linked with one another, forming a well-developed network, and numerous wrinkles running transversely were observed on the surface of the myoepithelial cells. Also, some myoepithelial cells in the terminal portion linked with those in the intercalated duct. Based on these findings, it is suggested that myoepithelial cells in the intercalated duct may function as a protective wall against constriction of the narrow lumen of the intercalated duct when it is subjected to pressure by the surrounding tissues.