Neonatal alcohol exposure produces more severe motor coordination deficitsin high alcohol sensitive rats compared to low alcohol sensitive rats

Prenatal exposure to alcohol can produce a number of behavioral alterations , including hyperactivity, learning deficits and motor impairments. However , the severity and nature of behavioral alterations varies markedly among c hildren of women who drink during pregnancy. One important determinant of t his variation may be genetic differences in the response to alcohol. Recent ly, we demonstrated that exposure to alcohol during development produced hy peractivity in rats bred for high alcohol sensitivity (HAS), but not in rat s bred for low alcohol sensitivity (LAS). These lines were selectively bred for extremes in alcohol-induced "sleep time." The present study investigat ed the effects of ethanol exposure during development on motor coordination later in life in both HAS and LAS rats. Using an artificial rearing proced ure, neonatal pups from each line were exposed to a binge-like alcohol trea tment on postnatal days (PD) 4-9. Within each line, one group was exposed t o ethanol (6.0 g/kg/day), one group served as an artificially reared contro l, and a third served as a normally reared control group. On PD 30, paralle l bar motor performance was evaluated. Exposure to ethanol during developme nt severely impaired motor performance in the HAS rats compared to their co ntrols. In LAS rats, early ethanol exposure produced only mild and nonsigni ficant effects on motor performance. Thus, HAS rats were more vulnerable to ethanol-induced motor deficits compared to the LAS rats. Importantly, ther e were no differences in peak blood alcohol level between the lines, indica ting that vulnerability to ethanol's teratogenic effects was not due to dif ferences in metabolic rate. These results suggest that genetic differences in response to alcohol may serve as a predictor for susceptibility to ethan ol's teratogenic effects. (C) 2000 Elsevier Science Inc. All rights reserve d.