Development of astroglia heterogeneously expressing Pax2, vimentin and GFAP during the ontogeny of the optic pathway of the lizard (Gallotia galloti): an immunohistochemical and ultrastructural study.

The successful regrowth of retinal ganglion cell (RGC) axons after optic nerve (ON) axotomy in Gallotia galloti indicates a permissive role of the glial environment. We have characterised the astroglial lineage of the lizard optic pathway throughout its ontogeny (embryonic stage 30 [E30] to adults) by using electron microscopy and immunohistochemistry to detect the proliferation marker PCNA (proliferating cell nuclear antigen), the transcription factor Pax2 and the gliofilament proteins vimentin (Vim) and GFAP (glial fibrillary acidic protein). PCNA(+) cells were abundant until E39, with GFAP(+)/PCNA(+) astrocytes being observed between E37 and hatching.