Transmission and scanning electron microscope studies on the surface coat of the oral mucosa in the rat.

Abstract

Following treatment with either Ruthenium red or Alcian blue, the exposed surface of oral mucosa from the rat was examined in either the scanning or transmission electron microscope. The oral surfaces of half the specimens were vigorously washed prior to treatment with Ruthenium red or Alcian blue. The appearance of all scanning electron microscope specimens was compatible with that seen in the transmission electron microscope. All the washed Ruthenium red and Alcian blue and the unwashed Ruthenium red specimens had a continuous layer of granular material over the oral surface of the epithelial cells. A thick precipitate of saliva covered the unwashed Alcian blue specimens. The probable reasons for the precipitation of saliva by the Alcian blue are discussed. The possible nature, origins and functions of the Ruthenium red and Alcian blue positive surface covering are discussed.