Neonatal choline supplementation ameliorates the effects of prenatal alcohol exposure on a discrimination learning task in rats

Prenatal alcohol exposure can disrupt brain development and lead to a myriad of behavioral alterations, including motor coordination deficits, hyperactivity, and learning deficits. There remains a need, however, to identify treatments and interventions for reducing the severity of alcohol-related neurodevelopmental disorders. Some of the alcohol-induced deficits in learning may be related to alterations in cholinergic functioning. Interestingly, there is a growing literature demonstrating that pre- and/or early postnatal choline supplementation can lead to long-term enhancement in learning and memory and cholinergic activity in rats. The present study examined whether such early choline supplementation might counter the effects of prenatal alcohol treatment on a visuospatial discrimination task. Pregnant Sprague-Dawley rats were randomly assigned to one of three prenatal treatment groups. One group received a liquid diet containing 35% ethanol-derived calories (EDC) from gestational day (GD) 6-20. A second group served as a pair-fed (PF) control group and the third group served as an ad lib lab chow (LC) control. On postnatal day (PD) 2, pups were assigned within-litter to one of three postnatal treatments: choline, saline vehicle, or no treatment. Choline and vehicle pups were intubated with a choline chloride solution or vehicle daily from PD 2 to 21, whereas the non-treated pups were handled daily but not intubated. On PD 45, subjects were tested on a visuospatial discrimination task. Ethanol-exposed subjects who were not treated neonatally with choline committed a significantly greater number of errors both during acquisition and during delayed discrimination training compared to both PF and LC controls. Neonatal choline treatment significantly improved performance on the discrimination task in all groups; however, the beneficial effects of choline were significantly larger in ethanol-exposed subjects. Indeed, the performance of ethanol-exposed pups treated with neonatal choline did not differ from any of the PF or LC groups on any measure. Thus, early postnatal choline supplementation significantly attenuated the effects of prenatal alcohol on this learning task. Importantly, these effects were not due to the acute effects of choline, but rather to longterm changes in brain and behavioral development. These data suggest that early dietary interventions may reduce the severity of fetal alcohol effects. (C) 2000 Elsevier Science Inc. All rights reserved.