A transgenic mouse model for the detailed morphological study of astrocytes

We have generated a transgenic mouse model in which astrocytes express an enhanced green fluorescent protein (EGFP) under the control of the mouse glial fibrillary acidic protein (GFAP) promoter. EGFP, which is characteristically found throughout the cell, was expressed in these animals even in astrocytic fine processes, and EGFP expressing cells demonstrated morphological characters of protoplasmic, fibrous, or reactive astrocytes. In contrast, GFAP immunoreactivity was found only in the perinuclear region and in the main processes. The transgenic mouse model therefore provides a valuable tool for the detailed morphological investigation of astrocytes.