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Published on: October 17, 2013
A Bast-like valve in the pigeon?
Rutger Hofman1, J M Segenhout, H P Wit
1Department of Otorhinolaryngology, University Medical Center Groningen, P.O. Box 30001, 9700 RB, Groningen, The Netherlands. r.hofman@kno.umcg.nl
Abstract:
The first description of the presence of a utriculo-endolymphatic valve in human fetuses was given by Bast in 1928. Since then this valve-like structure is called Bast's valve. Its exact function has not yet been established. The general opinion is that it has a protective function by having the possibility to separate the superior endolymphatic compartments of the labyrinth from the inferior compartment. Phylogenetically seen birds are the first vertebrates with a cochlear duct and a distinct inferior and superior part of the labyrinth. A structure in the pigeon inner ear, resembling Bast's valve in mammals, is described.
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