[Intracellular localization of alpha-fetoprotein and serum albumin in the central nervous system of the rat during fetal and postnatal development].

The morphological localisation of alphafetoprotein (AFP), serumalbumin (SA), transferrin and immunoglobulins (IgG) has been studied in the developing central nervous system of the Rat by immunocytochemical methods. Evidence is presented of a highly selective staining for AFP and SA, both proteins exhibiting the same topographical distribution. Practically all the areas of the brain and the spinal cord are stained at a given moment of the developmental process. The labeling is cytoplasmic and in the neuronal elements extends to their axonic and dendritic prolongations. The localization of AFP and SA in the nervous system may be related to the well known binding properties of these proteins for varied substances (estrogen and/or fatty acids). The morphological data presented here suggest that both proteins may be actively involved in the uptake of such substances by the cellular structures of the nervous tissue.