Objective: To investigate the effect of zinc supplementation on expression of MT-1 and MT-2 mRNA in placenta and small intestine of pregnant rats. Method: Eighteen healthy pregnant SD rats were randomly divided into two groups,normal control (ZC) and zinc supplement group (ZS). Rats in both groups were fed the same normal diet. Rats in ZC group drank deionized water and those in ZS group drank the water supplemented with 1.26 mmol/L Zn. At gestational 9.5d and 17.5d, serum zinc was determined by atomic absorption spectrophotometer and the expression of MT-1 and MT-2 mRNA of placenta and small intestine was examined by RT-PCR. Results: Serum zinc levels at gestational 9.5d and 17.5d were higher in ZS group. Relative expression of both MT-1 and MT-2 mRNA in placenta, MT-1 mRNA at gestational 17.5d and MT-2 mRNA at each time point were higher in ZS group. At gestational 9.5d, there was no difference between two groups in expression of MT-1 mRNA. Conclusion: The expression of MT-1 and MT-2 mRNA in placenta and small intestine was up-regulated by dietary zinc supplementation during pregnancy.

Objective:To investigate the effect of zinc supplementation on the expression profile of zinc transporters mRNA in placenta and small intestine of pregnant rats.Method:Eighteen pregnant SD rats were randomly divided into normal control(ZC)and zinc supplement group(ZS).Rats in ZC group drank deionized distilled water while those in ZS group drank water supplemented with zinc of 1.26 mmol/L.Placenta and small intestine were taken at gestational day 9.5 and 17.5,respectively.The expression of ZnT1,2,5 and 6 mRNA was examined by RT-PCR.Results:At gestational D9.5,the expression of placental ZnT1,2 and small intestinal ZnT1,2,6 mRNA was up-regulated,and placental ZnT5 mRNA down-regulated by dietary zinc supplementation.Dietary zinc intake had no effect on the expression of placental ZnT6 and small intestinal ZT5 mRNA.At gestational D17.5,the expression of placental ZnT5 and 6 mRNA was up-regulated by dietary zinc supplementation,and dietary zinc had no effect on the expression of placental and small intestinal ZnT1,2 mRNA.The expression of ZnT5 mRNA at gestational D17.5 in both groups was not detectable.Conclusion:Dietary zinc supplementation during pregnancy has significant effect on the expression profile of ZnT 1,2,5 and 6mRNA in placenta and small intestine of pregnant rats.