title: GFAP-immunoreactive perivascular glia in the chick optic tectum.
abstract: Immunocytochemical staining of the glial fibrillary acidic protein (GFAP) was utilized to characterize the processes of the astrocytes enveloping the vessel wall in the central nervous system. The study was carried out in the mesencephalic lobes of 18 and 20 incubation-day chick embryos and of 20 day chickens. A perivascular GFAP positivity was mainly detectable in the vessel portions running within the tectum white layers, while it was scarce, or absent, in the grey ones. The perivascular GFAP negativity in the tectum cellular layers was not considered result of the absence of astrocytic endfeet since our previous electronmicroscopical studies evidenced an almost complete perivascular astrocytic ring throughout the tectum layers at hatching time. Present data rather suggest that the expression of the GFAP-made intermediate filaments in developing astrocytes might be controlled by the surrounding microenvironment.
authors.affiliation: Institute of Human Anatomy, Histology and Embryology, University of Bari, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Virgintino
authors.forename: G
authors.initials: G
authors.lastname: Nicolardi
authors.forename: M
authors.initials: M
authors.lastname: Bertossi
authors.forename: B
authors.initials: B
authors.lastname: Nico
authors.forename: D
authors.initials: D
authors.lastname: Ribatti
authors.forename: G
authors.initials: G
authors.lastname: Ambrosi
authors.forename: L
authors.initials: L
authors.lastname: Roncali
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000737:chemistry* / Q000648:ultrastructure; D002642:Chick Embryo; D002645:Chickens; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis*; D007124:Immunoenzyme Techniques; D008636:Mesencephalon / Q000378:metabolism; D013477:Superior Colliculi / Q000098:blood supply / Q000737:chemistry* / Q000648:ultrastructure
chemical_list: D005904:Glial Fibrillary Acidic Protein