Ultrastructure of the Coelomic Lining in the Podium of the Starfish Stylasterias forreri
Date
1981
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Springer-Verlag
Abstract
UltrastructuraI examination of the podium of the asteroid
echinoderm Stylasteriasforreri reveals that cells of the coelomic epithelium and
cells of the retractor muscle are, in fact, components of a single epithelium. The
basal lamina of this unified epithelium adjoins the connective tissue layer of the
podium.
The principal epithelial cells in the coelomic lining are the flagellated
adluminal cells and the myofilament-bearing retractor cells. Adluminal cells
interdigitate extensively with each other and form zonular intermediate and
septate junctions at their apicolateral surfaces. The adluminal cells emit
processes which extend between the underlying retractor cells and terminate on
the basal lamina of the epithelium. Retractor cells exhibit unregistered arrays of
thick and thin myofilaments. The periphery of the retractor cell is characteristically
thrown into keel-like folds which interdigitate with the processes of
neighboring cells. Specialized intermediate junctions bind the retractor cells to
each other and anchor the retractor cells to the basal lamina of the epithelium.
The retractor cells are not surrounded by external laminae or connective tissue
envelopes.
It is concluded that the coelomic lining in the podium of S. forreri is a
bipartite epithelium and that the retractor cells of the podium are myoepithelial
in nature. There are no detectable communicating (gap) junctions between the
epithelial cells of the coelomic lining.
Description
Keywords
Biology
Citation
Richard L. Wood and Michael J. Cavey "Ultrastructure of the Coelomic Lining in the Podium of the Starfish Stylasterias forreri" Cell Tissue Res (1981) 218:449-473