Distribution of anionic sites during increasing tight junctional permeability in the rat submandibular gland

Abstract

The paracellular transport of salivary components from the interstitial space to the lumen was examined using microperoxidase as a tracer, and the distribution of anionic sites on the lateral cell membrane associated with the tight junction were observed utilizing ruthenium red and cationized ferritin. In the substance P-stimulated gland, we found the permeability of the tight junction was increased and the tight junctional region became negatively charged when compared with the resting gland. There were also changes in the anionic sites on the lateral cell membrane in the resting gland and in the secretory stimulated gland.