Expression and localization of aquaporins 8 and 9 in term placenta with oligohydramnios.

To test the expression and localization of aquaporins 8 (AQP8) and 9 (AQP9) in human term fetal membranes and placenta in both oligohydramnios and normal amniotic fluid volume (AFV) groups and to explore the association between aquaporin expression and oligohydramnios. Real-time polymerase chain reaction and immunohistochemistry were used to determine AQP8 and AQP9 expression levels and localization in amnion, chorion, and placenta, respectively. In addition, compared with the normal AFV group, the expression levels of both AQP8 and AQP9 in amnion in oligohydramnios group were significantly decreased, while their expressions in placenta were significantly increased. The expression level of AQP9 was also significantly decreased in chorion, while that of AQP8 was unchanged. Both AQP8 and AQP9 may play an important role in water flow both in intramembranous absorption and in placental water transfer. Our study offers the potential therapeutic approach for oligohydramnios.