[Effect of placental transferrin receptors on iron nutritional state of normal full-term gravidas and their newborns].

Sixty full-term gravidas were divided into four groups, normal insidious iron deficiency, mild iron deficient anemia and moderate iron deficient anemia, according to their iron nutritional state determined by the measurement of hematologic and iron biochemical indexes. The iron nutritional state of newborns in each group and the level and the affinity of transferrin receptor in placenta were also studied. The iron nutritional state of newborns was found to decrease mildly along with the decrease of their mothers' iron nutritional state, especially the decrease of serum ferritin, but the differences were not statistically significant. It was suggested that the iron nutritional state of newborns was relatively normal although their mothers were in severe iron deficiency. The differences of transferrin receptor levels were significant among the four groups, the mild IDA group had the highest level of transferrin receptor, which was 1.68 times of normal group and 1.77 times of moderate IDA group. The differences between each two groups were significant. The differences of dissociate constant (Kd) of transferrin receptor were not significant among the four groups, indicating that the iron metabolism between mothers and their babies was regulated not by changing the affinity of transferrin binding to its receptor but by changing the numbers of transferrin receptor to maintain the relative stableness of newborns iron nutritional state.