Left: Western blot analysis of GFAP expression in tissue homogenates. [1] protein standard, [2] rat brain, [3] rat spinal cord, [4] mouse brain, [5] mouse spinal cord, [6] pig brain, [7] rat recombinant GFAP, [8] human recombinant GFAP. Bands around 50 kDa correspond to alternative transcripts and proteolytic products of GFAP. Primary antibody was diluted 1:2,000. Note that this antibody has significantly stronger reactivity with pig and human GFAP as compared to rodent, suggesting that it binds to an epitope which is not totally conserved across mammalian sequences. Right: Analysis of GFAP expression in an adult rat cerebellum section by Immunohistochemistry. Primary antibodies: mouse anti-GFAP (red, 1:500), chicken anti-Parvalbumin (C-1814-50, green, 1:2,000). Blue: DAPI nuclear stain. IHC Method: Following transcardial perfusion of rat with 4% paraformaldehyde, brain was post-fixed for 24 hours, and free-floating 45 uM sections were stained. The GFAP antibody stains the processes of Bergmann glia and astrocytes. The Parvalbumin antibody labels perikarya and dendrites of Purkinje cells and interneurons in the molecular layer of the cerebellum. The staining on rodent tissues is specific but not as robust as on human material.