Korean J Obstet Gynecol.
2009 Aug;52(8):803-814.
Localization of aquaporin-3 in mouse placenta and its role
- Affiliations
-
- 1Department of Obstetrics and Gynecology, Pusan National University, School of Medicine, Busan. ohchoi@pusan.ac.kr
- 2Department of Physiology, Dong-A University College of Medicine, Busan, Korea.
Abstract
OBJECTIVE
Aquaporin (AQP) 3 is a small integral membrane protein that functions as a facilitated transporter of water and glycerol. To elucidate a role of AQP3 in placenta, changes in amniotic fluid composition and fetal growth were investigated using AQP3 null mice.
METHODS
Embryonic day 14,5 gestational sacs of wild-type and AQP3 kncok-out pregnant mice, thirty each, were used for this study. AQP3 localization and expression were assessed by immunohistochemistry and western blot.
RESULTS
AQP3 was highly expressed in basolateral membrane of visceral yolk sac cells of fetal membrane and syncytiotrophoblast cells of labyrinthine placenta. In contrast, AQP1 was expressed in apical membrane of visceral yolk sac cells and endothelial cells lining vasculature. There was no significant difference in normal placentation and differentiation from trophoblast stem cells between wild type and AQP3 null mice. However, AQP3 null mice had increased amount of amniotic fluid per gram of body weight and decreased osmorality of amniotic fluid with low concentrations of ions and solutes in amniotic fluid. In addition, AQP3 null mice pups were smaller than CD1 wild type mice.
CONCLUSION
AQP3 plays an important role in amniotic water balance and nutrient supply to developing fetus by facilitating transplacental transport of water and glycerol.
