Purpose: Thc goal of this study was to characterize the morphology of the m
ucinous layer on rabbit, bovine, owl, and human corneal endothelial cells.
Methods: Corneoscleral buttons were fixed using cetylpyridinium chloride to
stabilize "mucus" and the tissue was prepared for transmission electron mi
croscopy. Photomicrographs were measured to determine chi thickness of thc
endothelial and epithelial mucinous layer in the central cornea. Results: T
he endothelial mucinous layer was seen as a nearly uniform electrodense reg
ion on the apical aspect of the endothelium. it was found to be 0.9 mum, 0.
9 mum, 0.9 mum, anti 0.5 mum thick in rabbit, bovine, owl, and human, respe
ctively. The owl endothelium had an additional lass electrodense layer with
a granular appearance and a thickness of about 200 mum. The mucinous layer
on the epithelium was similar in appearance to that on the endothelium and
across species. Conclusions: The morphologic similarity of the endothelial
and epithelial mucinous layers is a serendipitous finding that should prov
e valuable in experimental design. Ultimately, it is hoped that studies of
the posterior corneal surface will deepen our knowledge of endothelial prot