Immunohistochemical demonstration of glycogen phosphorylase in rat brain slices

Paraffin-embedded sections from paraformaldehyde-fixed rat brain were stained immunocytochemically for glycogen phosphorylase brain isozyme BB, using a monoclonal mouse antibody and the biotin-strept-avidin method, with either horseradish peroxidase or beta-galactosidase as marker enzymes. Two cell types showed strong glycogen phosphorylase-immunoreactivity: Astrocytes and ependymal cells. Most intensive staining was observed in the cerebellar cortex, the neocortex and the hippocampus. Astrocytes in the cerebellar white matter stained positively. The choroid plexus cells stained poorly or not at all. Neurons throughout the brain were negative, as well as oligodendrocytes and bundles of myelinated nerve fibers. These data are consistent with the immunocytochemical localization of glycogen phosphorylase in astroglia-rich primary cultures derived from rat brain.