Role of aquaporin-9 in human placenta.

SZPILBARG NATALIA; LEVI LORENA; NOVAK MARIANO; IBARRA CRISTINA; DAMIANO ALICIA E

Santiago de Chile. Chile

Congreso; II Simposio Latinoamericano sobre Interaccion Materno-Fetal y Placenta; 2005

Placenta Association of the Americas- Grupo Latinoamericano de placenta

The expression and localization of aquaglyceroporins (AQP3, AQP7, AQP9) in the syncytiotrophoblast of human placenta were previously reported by us. In particular, the increase of AQP9 expression levels in preeclamptic placentas were not followed by water and mannitol transport. It is known that progesterone (P4) and the hypoxia inducible factor-1 (HIF-1) are augmented in preeclampsia. Therefore in the present study we studied the expression of AQP9 in explants from normal placentas treated for 24 h with 300ng/mL P4 or either 250 uM CoCl2, an inducer of HIF-1. Explant viability was controlled by beta-hCG level in the extracellular medium. AQP9 mRNA expression was measured by semiquantitative RT-PCR. Unidirectional fluxes of water, mannitol and urea were measured by radiolabeled techniques. AQP9 expression was higher in both, CoCl2 and P4 treatments than controls. Water and mannitol uptake decreased in explants treated with CoCl2 (82% and 51%) whereas they were increased in explants treated with P4 (40% and 63%). In addition, the uptakes in both conditions were significantly inhibited by 0.3mM HgCl2 (P