Alcohol induced cardiac malformations in the rat

A pattern of malformations described as the "fetal alcohol syndrome" (FAS), observed in the progeny of chronic alcoholic women, has been recently reported (Jones et al. 1973). Laboratory investigations in this area have focused primarily on the development of animal models which mimic the syndrome (Randall 1977; Chernoff 1977). In the present investigation, a single, intraperitoneal injection of an alcohol solution (0.03 ml/gm body weight of a 25% solution of 95% ethanol) was administered on day 10 of gestation to pregnant Sprague-Dawley rats. Fetuses were recovered on day 18 of gestation and examined for external malformations. Subsequent to standard fixation procedures utilizing Bouin's fixative, the tissues were serially sectioned at 8 micron and stained with hematoxylin and eosin. External malformations were infrequent in the experimental fetuses consisting of adactyly , wrinkled skin, and gastroschisis. Histological examination, however, revealed severe umbilical hernias and interatrial-septal defect in the experimental fetuses. The interatrial-septal defect was of the ostium secundum type and occurred in 41% of the offspring of the treated animals. It was not present in the control fetuses. This type of defect is recognized by the lack of a complete septum primum in the septal wall, permitting complete communication of the two atria at the level of the foramen ovale. The septum secundum usually remained intact.