Exencephaly and axial skeletal dysmorphogenesis induced by acute doses of ethanol in mouse fetuses.

Administration of single doses (0.02 ml and 0.03 ml/g body wt.) of a solution of absolute alcohol (25%, v/v) in saline to MF1 mice on day 8 of gestation resulted in significant fetal mortality, growth retardation and gross malformations of the fetuses at term. The malformations included cranioschisis with exencephaly, maxillary hypoplasia, exophthalmia and various digital anomalies. The exencephalic fetuses, cleared in KOH and stained with alizarin red revealed the absence of the skull vault and hypoplasia of the facial bones. The skull base indicated under ossification and overcrowding of the constituent bones resulting in severe reduction in the cranial volume and asymmetry of cranial base. These cranial skeletal malformations were accompanied by abnormalities of the vertebral bodies, arches, ribs and sternum. It is concluded that acute doses of alcohol during critical stages of neural tube development is deleterious to both the central nervous system (CNS) and axial skeleton in the mouse.