Delayed growth and maturation of astrocytic cultures following exposure to ethanol: electron microscopic observations

This investigation examined the effects of ethanol on the morphologic features of cultured rat astrocytes using a treatment paradigm that provided consistent exposure to ethanol at concentrations of 0.2%, 0.5%, or 1.0% (w/v). Cultures were assessed between 4 and 8 days in vitro during the logarithmic phase of growth; differences in culture growth, cell profile area and ultrastructural configuration were found. A dose-dependent inhibition of culture growth was observed after 48 and 96 h of ethanol exposure. In control cultures, the consequences of culture growth included the progressive crowding of cells, a concomitant reduction in the cell profile area, and increased cell-cell contact. On culture day 8, electron microscopic examination of control cultures demonstrated a complex stratified cellular layer, the junction of cells by puncta adhaerentia and the acquisition of intermediate filament bundles. In contrast, the impaired growth in ethanol-exposed cultures was associated with the retention of an extensive cell profile area suggesting restrained morphologic development. At the electron microscopic level, ethanol-exposed cultures showed a dose-dependent attenuation in both the depth and complexity of the cell layer. These findings indicated that the growth kinetics and morphologic development of astrocytic cultures are vulnerable to ethanol exposure at moderate and high levels. These findings were attributed to both ethanol cytotoxicity and a deprivation of cellular interaction resulting from the restricted population size.