GFAP Expression Related to Brain Development of Postnatal Mice

Abstract

Glial fibrillary acidic protein (GFAP) is an intermediate filament (IF) class III protein which also includes vimentin and nestin. This class is important for the brain to accommodate neural activities and changes during
development. The present study examined the changes of GFAP protein expression in the postnatal development of the mouse brain tissue. Mouse brains were sampled on postnatal day 3 (P3), 5 (P5) and 7 (P7). GFAP immunoreactivity was localized in the subventricular zone (SVZ) and subgranular zone (SGZ). Both in SVZ and SGZ, GFAP expression was acutely increased in the early phase of postnatal development then subsequently decreased from P3, P5, to P7. These opposing changes of GFAP were related to the increasing cortical thickness, brain and body weights. However, in SGZ of adult mice (mother mice, M), very high GFAP immunoreactivity was shown in the processes and cytoplasm of ramified shapes of the cells which revealed satellite and radial shapes. In conclusion, the increase in GFAP-positive astrocytes of both SVZ and SGZ was observed within 1 week of postnatal mice. Therefore, these findings provide valuable information on the developmental processes, and studies on GFAP regulation are useful to understand not only brain physiology but also brain developmental defect in offspring mice.