Immunocytochemical studies on the development of astrocytes, Müller (glial) cells, and oligodendrocytes in the rabbit retina

Abstract

Glial markers, namely antibodies to glial fibrillary acidic protein (GFAP), vimentin, galactocerebroside (GC), 04 antigen, and 08 antigen, were used to study the development of neuroglial cells in the postnatal rabbit retina. In histological sections radially oriented Müller cells were detectable at birth. They were weakly vimentin-positive and their labeling intensity increased during further development. Few vimentin-labeled astrocytes, situated in the nerve fiber layer, were detectable at birth, but of these few many were also GFAP-positive. The number of GFAP-positive astrocytes, all of which co-labeled with vimentin antibodies, increased during the following days. From postnatal day (P) 9-10 onward, the vimentin labeling seen in GFAP-positive astrocytes began to decline. In the adult rabbit most GFAP-positive astrocytes were only weakly vimentin-stained; some astrocytes even lacked detectable amounts of vimentin. Thus, astrocytes were found to be strongly vimentin-positive at birth, and strongly GFAP-positive but weakly vimentin-labeled by adulthood. Such a transition was not observed for Müller cells, which lacked detectable amounts of GFAP at all postnatal stages studied. In single cell suspensions, cells positive for the cell surface markers 04 antigen and GC were first detected at P6-7, 08 antigen-labeled cells were found one day later. Thus, the third class of neuroglial cells in the rabbit retina, the oligodendrocytes, seems to develop about one week later than astrocytes and Müller cells.