Aquaporin-2 expression in human endometrium correlates with serum ovarian steroid hormones.
The aim of the present study was to examine the expression of aquaporin-2 (AQP2), a member of the water channel family aquaporins (AQPs), in human uterine endometrium and its modulation of ovarian steroid hormone at the proliferative and secretory phases. Western blot, immunohistochemistry, and RT-PCR were employed in the present study. Western blot revealed a 29-kDa band that represented AQP2 in human endometrium. The expression of AQP2 in endometrium was confirmed by RT-PCR and immunohistochemical results. The immunohistochemical analysis demonstrated that AQP2 was prominent in luminal and glandular epithelial cells of endometrium. The levels of endometrial AQP2 expression changed during the menstrual cycle and were higher in the secretory endometrium than in the proliferative endometrium. A significantly high level of AQP2 was detected at the mid-secretory phase. There was a positive correlation between the levels of the endometrial AQP2 expression and the concentrations of the serum 17beta-estradiol (E2) or/and progesterone (P4). These data for the first time corroborate that AQP2 is expressed in human endometrium and that the expression of AQP2 in human endometrium might be regulated by E2 or/and P4. The changed expression of AQP2 at different phases of the menstrual cycle may be essential to reproductive physiology in human. The high level of endometrial AQP2 expression was observed at the mid-secretory phase, the time of embryo implantation, suggesting that AQP2 might play physiological roles in the uterine receptivity.
Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Zhejiang 310006, China.
Rong-Huan
RH
He
Jian-Zhong
JZ
Sheng
Qiong
Q
Luo
Fan
F
Jin
Bo
B
Wang
Yu-Li
YL
Qian
Cai-Yun
CY
Zhou
Xia
X
Sheng
He-Feng
HF
Huang
D000328:Adult; D051399:Aquaporin 2 / Q000235:genetics* / Q000378:metabolism*; D004717:Endometrium / Q000166:cytology / Q000378:metabolism*; D004958:Estradiol / Q000097:blood*; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D008597:Menstrual Cycle; D010053:Ovary / Q000378:metabolism*; D011374:Progesterone / Q000097:blood*; D021381:Protein Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
D051399:Aquaporin 2; D012333:RNA, Messenger; D011374:Progesterone; D004958:Estradiol