Mouse placental receptor for basic somatomedin following maternal ethanol administration

We have previously reported a reduction in the basic somatomedin (B-SM) binding activity of day-15 mouse placental membranes following 3 days of acute maternal ethanol administration. In the present experiments, we have investigated the effects of acute maternal ethanol administration early in gestation on the subsequent development of the placental B-SM receptor, and its relationship to alcohol-related embryofetal growth deficits. Following administration of aqueous ethanol (0.0, 3.6, 5.5 or 7.1 ml/kg) by gavage on days 7, 8 and 9 of gestation, there was no evidence of reproductive impairment in alcohol-treated dams, but there was a significant reduction in day-15 embryonic body weight. Crown-rump length was unaffected. There was no treatment-related difference in the percentage specific binding of [125I]-B-SM by day-15 placental membranes, or in maternal serum B-SM concentrations. These observations suggest that embryofetal growth restriction following maternal ethanol administration is not mediated directly by peripheral unresponsiveness of the B-SM receptor, at least when the exposure occurs early in or prior to placental receptor ontogeny.