Effect of ethanol on brain biogenic amines and phospholipids in the chick embryo

The role of biogenic amines and phospholipids in the acute and chronic effects of ethanol on chick embryo development were studied. Injection of ethanol into chicken eggs on the third day of embryonic development produced no deficits in body or brain weight in the 17-day-old embryo. Spontaneous fetal motility of the 17-day old embryo did not differ between vehicle- and ethanol-treated groups, but acute administration of ethanol decreased motility. Ethanol decreased dopamine and homovanillic acid, while the level of serotonin and 5-hydroxyindoleacetic acid did not change in the 17-day-old chick embryo brain. Furthermore, lysophosphatidylcholine, phosphatidylcholine and phosphatidyl-ethanolamine turnover was decreased by ethanol. Ethanol decreased embryo viability in a dose-dependent manner as early as day 7. At this time, radiolabeled ethanol could be detected in the embryo. Thereafter, the levels of radiolabeled ethanol in whole embryos or embryo brains revealed continual exposure to ethanol throughout development. Our data suggest that monoaminergic neurons are involved in the development of ethanol tolerance through phospholipid synthesis in the chick embryo brain.