The Fine Structure and Elemental Analysis of Keratinized Epithelium of the Filiform Papillae Analysis on the Dorsal Tongue in the American Alligator (Alligator mississippiensis)

Abstract

The filiform papillae of subadult alligator (120cm-260cm total length) tongues are examined by scanning electron microscopy and electron microprobe analysis. The filiform papillae form cone-like structures and are observed over the entire dorsal surface of a relatively long tongue with a round tip. The filiform papillae are composed of four layers; outer, upper intermediate, lower intermediate, and basal layer. The keratinized epithelial cells are analysed by the sulphur (S), and nitrogen (N) content levels. The S content is higher than that of N.-In the anterior side of the filiform papillae, this content is lower than that in the posteriors. The S content is highest of all at about 2 μm in depth from the surface. These results suggest that the use of S concentration measurements may serve to be an effective tool for a simple, offhand evaruation of keratinization. © 1990, Editorial Board of Okajimas Folia Anatomica Japonica. All rights reserved.