The expression of aquaporin 8 and aquaporin 9 in fetal membranes and placenta in term pregnancies complicated by idiopathic polyhydramnios.
BACKGROUND
Aquaporins are a family of membrane-bound water channel proteins that regulate the flow of water across a variety of biological membranes. The expression of aquaporin 8 and aquaporin 9 has been demonstrated in human chorioamniotic membrane and placenta. But their roles in the pathophysiology of polyhydramnios are unclear.


OBJECTIVE
To study the expression of aquaporin 8 and aquaporin 9 in fetal membranes and placenta in term pregnancies complicated by idiopathic polyhydramnios and to explore the association between aquaporin expressions and polyhydramnios.


METHODS
The placentas were collected from 51 patients who underwent elective Cesarean sections at term, of which 21 cases had idiopathic polyhydramnios and the other 30 had normal amniotic fluid volume.


METHODS
Real-time polymerase chain reaction and immunohistochemistry techniques were used to determine the expression and localization of aquaporin 8 and aquaporin 9 in the amnion, chorion and placenta.


RESULTS
Expression of aquaporin 8 and aquaporin 9 was detected in the amnion, chorion and placenta and located in amnion epithelia, chorion cytotrophoblasts and placental trophoblast. Compared to normal amniotic fluid volume group, the expression of aquaporin 8 in amnion, and aquaporin 9 in amnion and chorion, were significantly increased in idiopathic polyhydramnios group; however, their expression in the placenta was significantly decreased.


CONCLUSIONS
When polyhydramnios occurs, expression of aquaporin 8 and aquaporin 9 in fetal membranes and placenta is an adaptive change, which may be involved in the regulation of amniotic fluid volume. However, the modulation factors of the aquaporin 8 and aquaporin 9 expressions need further study.
Zhu
Xueqiong
X
Department of Obstetrics and Gynecology, the Second Affiliated Hospital of Wenzhou Medical College, Wenzhou 325027, China. zjwzzxq@163.com
Jiang
Shanshan
S
Hu
Yingchun
Y
Zheng
Xiaoqun
X
Zou
Shuangwei
S
Wang
Yuhuan
Y
Zhu
Xuejie
X
D000222:Adaptation, Physiological; D000328:Adult; D000650:Amnion / Q000378:metabolism*; D000653:Amniotic Fluid; D020346:Aquaporins / Q000235:genetics / Q000378:metabolism*; D002585:Cesarean Section; D002823:Chorion / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D005865:Gestational Age; D006801:Humans; D010920:Placenta / Q000378:metabolism*; D006831:Polyhydramnios / Q000175:diagnosis / Q000378:metabolism* / Q000503:physiopathology; D011247:Pregnancy; D047929:Term Birth; D055815:Young Adult
C109669:AQP9 protein, human; D020346:Aquaporins; C108330:aquaporin 8