Augmented endothelial nitric oxide synthase (eNOS) protein expression in human pregnant myometrium: possible involvement of eNOS promoter activation by estrogen via both estrogen receptor (ER)alpha and ERbeta.
The aim of the present study was to investigate the possible contribution of estrogen to pregnancy-associated modulation of nitric oxide production in the human myometrium during pregnancy. Both endothelial nitric oxide synthase (eNOS) and inducible NOS (iNOS) proteins were clearly expressed in the non-pregnant myometrium and were elevated in the first trimester of pregnancy. Oral contraceptive pills augmented eNOS, but not iNOS, protein expression in the non-pregnant human myometrium. In cultured human myometrial cells, estrogen receptor (ER)alpha and ERbeta expression was extremely low. Therefore, we used either ERalpha or ERbeta expression vector to investigate the effect of 17beta-estradiol treatment on eNOS promoter activity using eNOS promoter/luciferase vector in cultured human myometrial cells. 17beta-estradiol treatment significantly augmented eNOS promoter activity in cells co-transfected with either ERalpha or ERbeta, and this augmentation was dose-dependently suppressed by ICI 182780, an estrogen antagonist. These data suggest the possibility that both ERalpha and ERbeta are involved in the estrogen-associated regulation of eNOS gene expression in the human myometrium.
Kakui
Kazuyo
K
Department of Gynecology and Obstetrics, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Itoh
Hiroaki
H
Sagawa
Norimasa
N
Yura
Shigeo
S
Korita
Daizo
D
Takemura
Maki
M
Miyamaoto
Yoshihiro
Y
Saito
Yoshihiko
Y
Nakao
Kazuwa
K
Fujii
Shingo
S
D000328:Adult; D015153:Blotting, Western; D002478:Cells, Cultured; D004717:Endometrium / Q000187:drug effects; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D004997:Ethinyl Estradiol / Q000494:pharmacology; D005260:Female; D000077267:Fulvestrant; D017930:Genes, Reporter / Q000235:genetics; D006801:Humans; D007120:Immunochemistry; D032389:Myocytes, Smooth Muscle / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D009215:Myometrium / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000096:biosynthesis / Q000235:genetics*; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; D009644:Norgestrel / Q000494:pharmacology; D011247:Pregnancy / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000096:biosynthesis; D011960:Receptors, Estrogen / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015533:Transcriptional Activation; D014162:Transfection
D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D012333:RNA, Messenger; D011960:Receptors, Estrogen; D000077267:Fulvestrant; D009644:Norgestrel; D004997:Ethinyl Estradiol; D004958:Estradiol; C496319:NOS2 protein, human; C496314:NOS3 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III