[Three-dimensional histoarchitectonics of the larval epidermis of the grass frog]

We have conducted theoretical and experimental study of the three-dimensional structure of epidermis in the larva of the grass frog. Three-dimensional modeling of cell shape and mutual arrangement yielded several variants of cell-to-cell connections at the apical, basal, and intermediary levels of the cell sheet. Concepts of the normal and inverted orientation of the epithelial sheet have been introduced, and arguments for the existence of translation symmetry in this sheet were presented. At least two topological variants of three-dimensional organization can be found in the larval epidermis of the grass frog. Comparison of theoretical concepts and experimental results allowed us to conclude that the models developed by us are in good agreement with actual existing patterns of the epithelial structure; these models contribute to better reconstruction of their three-dimensional structure.