Properties of phosphorylated glial fibrillary acidic protein in brain slices of guinea pig, mouse and rat

1. Brain micro-slices from guinea pig, mouse and rat were incubated in Krebs-Ringer Na- HEPES buffered medium containing [32P]-phosphate and characterized by immunoblotting with polyclonal antibody to glial fibrillary acidic protein (GFAP). 2. GFAP presented small differences in two-dimensional electrophoretic mobility. 3. The phosphorylation of GFAP was dependent on Ca2+ in the incubation medium in adult animals. 4. Both the immunocontent and level of phosphorylation of GFAP were higher in hippocampus than in cerebral cortex of all the three species