INVESTIGADORES
SZPILBARG Natalia
congresos y reuniones científicas
Título:
The expression of aquaporin 4 decreases in preeclamptic placentas
Autor/es:
DIETRICH VALERIA; SZPILBARG NATALIA; ABAN CYNTIA; SILBERSTEIN CLAUDIA; ZOTTA ELSA; DAMIANO ALICIA ERMELINDA
Lugar:
Geilo
Reunión:
Congreso; IFPA Meeting 2011; 2011
Institución organizadora:
IFPA
Resumen:
The syncytiotrophoblast of human term placenta (hST) plays an important role throughout pregnancy because it is the site of nutrient exchange. The transport of metabolites, ions and water from mother to fetus could take place primarily via transcellular routes.Water transport across hST may be facilitated by aquaporins (AQPs). In some pathological states such as preeclampsia, the trophoblast invasion of the spiral arteries leads to a failure to establish an adequate uteroplacental blood flow generating a relatively hypoxic trophoblast tissue attenuating considerably the transport functions of the hST. We have first reported that water transport across the preeclamptic placentas was dramatically decreased compared to normal ones and that the expression of AQP3 and AQP9 was altered. Recently, some authors have found that AQP4 expression decreased along gestation in hST and endothelium of normal human placentas. In addition, other authors have reported that brain AQP4 expression changed under hypoxic conditions. Objective: The aim of the present work was to study AQP4 protein expression in the hST from normal and preeclamptic placenta and in a model of ischemia-reperfusion [hypoxia-reoxygenation] type insult. Methods: AQP4 expression was evaluated by Western blot and immunohistochemistry in normal, preeclamptic placentas and normal placental explants cultured in normoxia, hypoxia, and in hypoxia/reoxygenation conditions. Results: We found that AQP4 was located in the apical membranes of hST and in the endothelium of normal placentas but it was almost undetectable in preeclamptic placentas. When explants were cultured under hypoxic conditions, AQP4 expression increased in both hST and endothelium but decreased after reoxygenation treatment. Conclusions: Alterations in AQP4 expression as a consequence of the different oxygenation conditions may explain the changes observed in water transport across preeclamptic placentas.