MATURATION OF CEREBELLAR GRANULE CELLS IS DELAYED IN CULTURES DERIVEDFROM ETHANOL-TREATED CHICK-EMBRYOS - SURVIVAL AND PROLIFERATION STUDIES

Previous studies from this laboratory have shown that ethanol administ ration to chick embryos during embryonic days 1-3, a critical period o f neuroembryogenesis, differentially affects primordial CNS structures . In this study, chick embryos were treated in ovo with ethanol (10 mg /50 mu l/day) at E1 to E3. At 14 days of embryonic age cerebellar (E14 CE) granule cell cultures were prepared from both control and ethanol- treated embryos. Growth patterns were evaluated morphologically and th e neuronal nature of these cultures was evaluated immunocytochemically . E14CE granule cell cultures exhibited neurofilament immunoreactivity demonstrating the neuronal-nature of these cultures. In addition E14C E granule cultures contained numerous glutamatergic neurons as assesse d by positive glutamate immunoreactivity and also some GABAergic neuro ns as assessed by positive GABA immunoreactivity. Cultures derived fro m both control and ethanol-treated embryos were labeled with H-3-thymi dine and assessed for effects on survival and proliferation in culture . Cultures derived from ethanol-treated embryos showed a higher rate o f proliferation and survival during the first 3 days in culture as com pared to those derived from controls. However, after 3 days in culture , survival was lower in the cultures from ethanol-treated embryos as c ompared to those derived from controls. We interpret these findings to mean that (a) ethanol arrested cerebellar granule cell development at an immature state; (b) immature neurons have a higher survival capaci ty than differentiated neurons; and (c) ethanol accelerates normal neu ronal cell death as previously reported.