Expression of the Na(+)-H+ exchanger isoform-1 and cyclooxygenases in human placentas: their implications in preeclampsia.
The sodium hydrogen exchanger isoform, NHE-1 plays an important role in electrolyte and water homeostasis. These functions are compromised in pregnancies complicated with preeclampsia. At present it is not known whether NHE-1 expression is altered during preeclampsia. In the present study the placental level of NHE-1 protein was measured using immunoblotting. Since prostaglandins regulate the secretory and absorptive functions, the levels of prostaglandin E-2 as well as the expression of cyclooxygenase-1 and -2 were also estimated. The amount of NHE-1 protein and cyclooxygenase-2 was reduced in preeclamptic placentas, whereas the level of cyclooxygenase-1 remained unaltered. In contrast, prostaglandin E-2 concentration was higher in preeclampsia. Suppression of NHE-1 might render the placenta with impaired uptake of water and electrolytes and therefore may be involved in the pathogenesis of preeclampsia. While prostaglandin E-2 may play a role in preeclampsia, these findings discount the induction of cyclooxygenase-genes for this increase.
D000328:Adult; D005260:Female; D006801:Humans; D010920:Placenta / Q000201:enzymology / Q000378:metabolism*; D011225:Pre-Eclampsia / Q000209:etiology*; D011247:Pregnancy; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis*; D020033:Protein Isoforms; D017923:Sodium-Hydrogen Exchangers / Q000096:biosynthesis*