Effect of prenatal ethanol exposure during the brain growth spurt of the guinea pig

Abstract

This study tested the hypothesis that prenatal ethanol exposure during the last third of gestation, including the brain growth spurt (BGS), in the guinea pig produces neurobehavioural teratogenicity, manifesting as brain growth restriction and hyperactivity. Pregnant guinea pigs (term, about gestational day (GD) 68) received oral administration of ethanol (2 g/kg maternal body weight per day on GD 43 and/or GD 44 and then 4 g/kg maternal body weight per day from GD 45 to GD 62), isocaloric-sucrose/pair-feeding, or water. Maternal blood ethanol concentration (BEC) on GD 57 or 58, at 1 h after the daily dose, was 340±76 mg/dl ( n=8). Ethanol treatment decreased brain, cerebral cortical, hippocampal, and cerebellar weights at GD 63 ( P<0.05), and decreased brain and cerebral cortical weights at postnatal day 10 ( P<0.05), with no effect on body weight and no apparent effect on spontaneous locomotor activity. The data demonstrate that, in the guinea pig, prenatal ethanol exposure during the last third of gestation, including the BGS, decreases brain weight that persists into postnatal life, which is associated with growth restriction of the cerebral cortex. However, this prenatal ethanol exposure regimen, including the BGS, does not increase spontaneous locomotor activity in contrast to the persistent hyperactivity that occurs after chronic ethanol exposure throughout gestation.