Neuronal intermediate filament in the developing rat retina

The distribution of peripherin mRNA in adult rat retinal ganglion cells revealed by in situ hybridization was relevant to the distribution of immunoreactivity to anti-peripherin. Peripherin positive ganglion cells began to differentiate from the 13th gestational day. These peripherin positive ganglion cells expressed alpha-internexin from the early phase of differentiation and majority of the peripherin positive ganglion cells completed their migration by the 17th gestational day. The optic nerve layer was gradually enlarged during the 15-17th gestational day. However, unlike adult retina, neurofilament triplets were not revealed in the prenatal optic nerve. A different group of neurons with alpha-internexin without peripherin increased during the 15-19th gestational day and neurons of the internal nuclear layer seemed to transiently express alpha-internexin because they were seen in the internal nuclear layer above horizontal cells on the 19th gestational day. Although horizontal cells were clearly identified in the retina on the 19th gestational day, calbindin 28KD was not revealed in this stage.