铁是婴幼儿生长发育必需的微量元素，铁缺乏是导致婴幼儿贫血的重要因素，二价金属离子转运蛋白1（DMT1）是肠道铁吸收通路的主要蛋白，但是在婴幼儿铁吸收中发挥的作用与机制尚不明确。本研究采用Ussing Chamber技术建立哺乳期大鼠肠道铁吸收模型，检测不同肠段的铁离子的转运量，明确哺乳期大鼠铁吸收的关键肠段；通过对缺铁性贫血新生大鼠灌胃不同剂量的硫酸亚铁，结合DMT1的抑制剂与激活剂，调控肠道上皮细胞DMT1蛋白表达，测定肠道铁转运速率，明确DMT1在肠道铁吸收的作用；通过腹腔注射脂多糖，诱导哺乳期大鼠铁调素过表达，测定DMT1在肠道上皮细胞的定位与表达，揭示DMT1在哺乳期大鼠肠道铁吸收中的调控作用机制。研究结果为进一步完善婴幼儿肠道铁吸收机制提供重要依据，同时对实现婴幼儿配方乳粉中铁的精准添加具有指导意义。

Iron is essential for infant growth and development, and iron deficiency is the leading cause of anemia for infants. Divalent metal-ion transporter 1 (DMT1) plays important role in intestinal iron transport. However, the role of DMT1 during iron absorption in suckling infants is not clear. In this proposal, Ussing Chamber will be used to study mechanistic aspects of intestinal iron transport in suckling rats. After establishing the model, iron flux of different gut segments will be measured to determine the main intestinal iron absorption site. Iron deficiency anemia neonatal rats will be gavaged with different concentrations of ferrous sulfate. DMT1 inhibitor and activator will also be used to regulate intestinal DMT1 expression. Iron flux will be measured to determine the function of DMT1 in iron absorption. Further, suckling rats will be injected intraperitoneally with LPS to induce hepcidin overexpression. The expression and localization of DMT1 in the apical membrane of enterocytes will be studied to clarify the regulation mechanism of DMT1 during intestinal iron absorption in suckling rats. Ultimately, these studies will facilitate the understanding of intestinal iron absorption during suckling, and provide guidelines for the precise design of the addition of iron in infant formula.