title: Activity of NA(+)/H(+) exchangers alters aquaporin-mediated water transport in human placenta.
abstract: The intracellular pH (pHi) of syncytiotrophoblasts is regulated, in part, by Na(+)/H(+) exchanger (NHE)-1, NHE-2, and NHE-3. Failures in pHi homeostasis could alter critical cellular functions such as water transport and cell volume. Here, we evaluated whether alterations in syncytiotrophoblast pHi could modify water uptake mediated by aquaporins (AQPs) and the contribution of NHEs to this mechanism. We showed that changes in syncytiotrophoblast pHi did not affect water uptake in the presence of functional NHEs. However, inhibition of NHEs alters transcellular water transport mediated by AQPs in acidosis. These results suggest an interaction between placental AQPs and NHEs in the regulation of water uptake during acidotic states.
authors.affiliation: Laboratorio de Biología de la Reproducción, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO), CONICET, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Valeria
authors.initials: V
authors.lastname: Dietrich
authors.affiliation: Laboratorio de Biología de la Reproducción, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO), CONICET, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina; Cátedra de Biología Celular y Molecular, Departamento de Ciencias Biológicas, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina. Electronic address: adamiano@ffyb.uba.ar.
authors.forename: Alicia E
authors.initials: AE
authors.lastname: Damiano
mesh_terms: D020346:Aquaporins / Q000378:metabolism*; D001692:Biological Transport / Q000502:physiology; D005260:Female; D006801:Humans; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D017923:Sodium-Hydrogen Exchangers / Q000378:metabolism*; D014327:Trophoblasts / Q000378:metabolism*; D014867:Water / Q000378:metabolism*
chemical_list: D020346:Aquaporins; D017923:Sodium-Hydrogen Exchangers; D014867:Water
keywords: AQPs; NHEs; Water transport; pHi