An Investigation of the Effects of Acute vs. Chronic Ethanol Exposure on the Embryonic Chick Brain: A Model of Fetal Alcohol Syndrome-Associated Brain Damage

Abstract

The chick embryo was used as a model for Fetal Alcohol Syndrome (FAS) to perform a dose-response study of brain damage. Two common maternal drinking patterns were compared. Chronic drinking was simulated by administering 2 ?l doses of 0.5% ethanol eight times during the development of the embryo. Acute drinking was simulated by administering 5 ?l doses of 0.5% ethanol three times during development. Significant differences (p < 0.01) were observed between the two treatment groups with embryos in the acute group manifesting considerably more brain damage (as determined by brain weight and brain weight-to-body weight ratio measurements) than embryos in the chronic treatment group. This result indicates that the amount of brain damage incurred as a result of alcohol consumption is a function of blood alcohol concentration levels. No significant differences (p > 0. 01) were observed among the treatment groups in neuron counts from the right cerebral hemispheres of the brains. This result indicates that the mechanism of FAS-related CNS damage does not occur through the interference of alcohol with cell division.