Immunoreactive Detection of Glial Fibrillary Acidic Protein (GFAP) from the Brain of Bombyx mori

Glial fibrillary acidic protein (GFAP) is the primary intermediate filament protein as a marker for the identification of astrocytes in the central nervous system in vertebrates. This present study was performed to identify GFAP-immunoreactive neurons in invertebrate (moth) by the light microscopy immunohistochemistry and immunoblotting. Our results indicated the presence of GFAP-like positive cell processes and cell bodies in the developing stages. The amount of GFAP immunoreactivity was maximized in the 3rd instar larva but diminished it, approaching to 5th instar. This changed amount of GFAP was also confirmed by immunoblotting with developing stages. GFAP immunoreactivity was also observed in both axons within nervi corpora cardiaci (NCC) I + II and corpora allata (NCA). We suggest that this glial filament protein may be conserved in the evolution of the invertebrate nervous systems and that it may be used as a label for some types of glial cells and as neurotransmitter of neuromodulator in the moth.