Ultrastructure of the saccus endolymphaticus and leptomeninges of the domestic fowl Gallus gallus f. domestica
Klika, E.; Zajícová, A.
Folia Morphologica 36(4): 423-430
1988
ISSN/ISBN: 0015-5640 PMID: 3229693 Document Number: 324149
As a sequel to a development study, the authors describe the structure and localization of the SE in postnatal ontogenesis and in adult fowls (Gallus domesticus). In adult fowls, as distinct from mammals, the SE is localized in the subarachnoid space, in the angle between the medulla oblongata and the cerebellum, so that roughly half of its is covered by the arachnoidea. The part of its surface facing the medulla oblongata is in contact with the subarachnoid space, or the lining of the pia mater. The SE is a relatively bulky saccular structure with a markedly folded surface. Its basic cytological characteristics correspond to the findings at the end of tembryonic development. The cells of which the SE epithelium is composed form a single layer with a richly everted basal labyrinth, whose structure corresponds in principle to the structure of the basal labyrinth of the efferent duct epithelium of the salt glands of birds. The apical zone of the cells is surmounted by microvilli. An endocytotic apparatus and marked vesiculation, together with the formation of a basal labyrinth, testify to the transport function of the epithelium. The SE is wrapped in constinuous mesenchymal epithelium of the subarachnoid space, in which it is suspended by collagen trabeculae.