Gestational alcoholism and fetal zinc accretion in Long-Evans rats.

An animal study was conducted to examine the effects of alcohol consumption on placental transfer of zinc during late gestation. Throughout pregnancy, rat dams were fed a nutritionally adequate diet with 30% of total kcal as alcohol. On days 18 and 21 of pregnancy, zinc-65 was injected subcutaneously into the dams and the dams were killed 24 hours later; tissues were removed for analyses. Maternal serum, liver, kidney, and heart zinc decreased with gestational age while total fetal zinc increased. Neither the decrease in maternal organ zinc nor fetal accretion were affected by alcohol consumption. Placental zinc concentration also declined with developmental age and was not influenced by alcohol consumption. The decrease in placental zinc was accompanied by a decrease in zinc associated with 4-10-kD proteins of placental cytosol. Our results suggest that zinc flux during late rat gestation is a well-regulated process that is not influenced by alcohol consumption. Coordination of the transfer apparently is influenced by maternal blood concentration of zinc, placental zinc-binding proteins, and fetal demand for zinc.