Influence of zinc on ethanol-induced placental changes in the rat.

For normal fetal growth and development, an ample supply of nutrients and oxygen is essential. The placenta is the conduit for nutrient transfer and thus any factor that alters normal placental structure and function may adversely affect the nutritional status of the fetus. The effect of ethanol ingestion and zinc supplementation on placental structure was investigated by the simultaneous administration of ethanol and zinc to pregnant Sprague-Dawley rats from gestational day 6 through 12. One group of animals was given an ethanol liquid diet, a second group received the ethanol liquid diet plus zinc, and another group was pair-fed a control liquid diet. Placentas were recovered on day 20 of gestation. The mean placental weight in the ethanol group was significantly higher than that in either the pair-fed control or the ethanol plus zinc group. The ethanol-treated group revealed more stagnated blood in the basal-decidual and in the basal-labyrinthine junctions. Intervillous spaces in the labyrinthine zones were markedly dilated and filled with more blood corpuscles compared to the pair-fed control group. The giant cells of the basal zone were also larger in size in the ethanol-treated group. The frequency of occurrence of stagnated blood in either the labyrinthine zone and in the basal-labyrinthine junction was less in the ethanol plus zinc group compared to the ethanol group.