Reduced expression of Na⁺/H⁺ exchanger isoform 3 (NHE-3) in preeclamptic placentas

Although the etiology of preeclampsia is unknown, accumulated evidence suggests that the expression of a variety of syncytiotrophoblast transporters is reduced or abnormal. Here, we have examined the expression of NHE-3 in preeclamptic placentas. We found that NHE-3 expression significantly decreased and its labeling was almost undetectable in the cytosol of syncytiotrophoblast cells. Even though the inductor mechanisms of NHE-3 decrease are not clear yet, we speculated that alterations in TNF-α and aldosterone levels observed in preeclampsia might be downregulating NHE-3 expression. Further studies are needed to define whether these alterations play a direct role either in the pathogenesis or in the adaptative response of preeclampsia.