[Normal cerebral aging: study of glial reaction].

Glial fibrillary acidic protein (GFAP), a biochemical marker of astrocytes and glial reaction, was quantified in different brain areas from 16 non-demented patients with a mini mental state score > 25/30 and aged from 21 to 95 years. For each brain, we analyzed the hippocampus (H), the parahippocampus gyrus (GPH) and the neocortical Brodmann areas 9, 22, 39, 44. The quantification of GFAP was performed on the different brain homogenates treated with SDS, using a Western blot method and an immunodetection with a monoclonal antibody against human GFAP. The quantity of GFAP found in the hippocampus and the parahippocampal region were significantly increased as a function of age (p < 0.001). This was not observed for neocortical areas. It has been shown that hippocampal and parahippocampal regions are specifically affected by the Alzheimer-type degenerating process during aging. Glial reaction, as visualized by immunoblotting, could be directly linked to this phenomenon.