GLIAL FIBRILLARY ACIDIC PROTEIN EXPRESSION IN RAT-BRAIN AND IN RADIALGLIA CULTURE IS DELAYED BY PRENATAL ETHANOL EXPOSURE

The alterations in astrocyte proliferation and differentiation induced by prenatal exposure to alcohol (PEA) suggest that ethanol exposure a ffects the radial glial cells, the main astrocytic precursors. We have investigated the effects of ethanol on the early stages of astrogliog enesis by analyzing the developmental pattern of vimentin and glial fi brillary acidic protein (GFAP) immunoreactivity and their mRNA levels during embryonic/fetal brain development and in radial glia in primary culture. GFAP appeared late in gestation and at day 5 of culture of r adial glia, whereas GFAP mRNA was first detected on fetal day 15 and i ncreased in content on fetal day 21. In contrast, the levels of viment in and its mRNA were high at fetal day 15 but decreased on day 21. Alc ohol exposure delays the appearance of GFAP and its mRNA and significa ntly decreases the GFAP expression in fetal brain and in primary cultu re of radial glia. In addition, some morphological alterations were ob served in PEA glial cells in culture. These results demonstrate that a stroglial precursor cells are damaged by prenatal exposure to ethanol and suggest that abnormalities in the astrogliogenesis may underlie th e disruption in neuronal migration and other CNS alterations observed after prenatal ethanol exposure.