High affinity binding of transferrin in cultures of embryonic neurons from the chick retina.

Immunohistochemical and autoradiographic analysis of neuronal cultures from embryonic day 8 (E8) and day 11 (E11) chick retina indicate that transferrin receptors and binding sites are present on soma and neurites. Cultures maintained in the presence of transferrin expressed elevated transferrin binding due to an increase in the number of transferrin receptors. Cultures from E11 neural retina exhibited a decrease in transferrin binding when compared to E8 cultures. This appears to be due to a decrease in the number of binding sites. Neurons maintained in a transferrin-free medium supplemented with 0.4 microM of iron sulfate generally expressed slight increases in transferrin binding.