Basal lamina at the epithelial-connective tissue junction in the rat forestomach, esophagus, tongue and palate: scanning electron microscopic study.

The squamous epithelium lining the rat foregut was removed by incubating fresh, unfixed specimens in 2N sodium bromide. The surface morphology of the exposed subepithelial basal lamina was examined by scanning electron microscopy. Areas examined included hard and soft palates, oropharynx, tongue, esophagus, and forestomach. The basal lamina was continuous were not present at all sites. The saucer-like defects of lymphocyte migration that are present in the basal lamina beneath the squamous epithelium of the skin were not observed in rat foregut. The epithelial-connective tissue interface of the rat esophagus does not have the coiled and branched papillae seen in esophagi of adult humans. The three dimensional shapes of the connective tissue cores of the various lingual papillae are well-demonstrated by this technique and are distinct. The basal lamina of the hard and soft palates are also distinct.