title: Expression of nitric oxide synthase isoforms in the human placenta is not altered by labor.
abstract: Nitric oxide has various biological activities including smooth muscle relaxation, anti-inflammatory activity, anti-coagulatory activity. As the human placenta is known to express nitric oxide synthases, this study investigated the possible effect of labor on the expression of endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS) in human placental tissues at term. Both eNOS and iNOS mRNA expression in placental tissues in labor were significantly higher than those in the amnion, chorion laeve, decidua vera and myometrium. The eNOS mRNA and protein expressions in placental tissues in labor (n = 12) were 1.6023 +/- 0.1652 (eNOS/GAPDH, mean +/- SEM) and 12.8 +/- 1.3 arbitrary units (AU), respectively, which were similar to those not in labor (n = 10), 1.5806 +/- 0.2042 (eNOS/GAPDH) and 11.4 +/- 1.8 AU. The iNOS mRNA and protein expressions in the placental tissues in labor were 1.2831 +/- 0.2436 (iNOS/GAPDH) and 10.7 +/- 2.1 AU respectively, similar to those not in labor, 1.9254 +/- 0.8004 (iNOS/GAPDH) and 13.3 +/- 1.8 AU. The guanosine 3',5'-cyclic monophosphate (cGMP) concentration in the placental tissues in labor was 23.6 +/- 1.4 fmol/g wet tissue, similar to that not in labor, 26.1 +/- 2.0 fmol/g wet tissue. These findings suggest that nitric oxide production in the human placenta is maintained during labor.
authors: Department of Gynecology and Obstetrics, Kyoto University Graduate School of Medicine, Japan.
authors: Kazuyo
authors: K
authors: Kakui
authors: Norimasa
authors: N
authors: Sagawa
authors: Hiroaki
authors: H
authors: Itoh
authors: Shigeo
authors: S
authors: Yura
authors: Daizo
authors: D
authors: Korita
authors: Maki
authors: M
authors: Takemura
authors: Mercy A
authors: MA
authors: Nuamah
authors: Shingo
authors: S
authors: Fujii
mesh_terms: D006152:Cyclic GMP / Q000378:metabolism; D005260:Female; D006801:Humans; D007743:Labor, Obstetric / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000235:genetics / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; D009994:Osmolar Concentration; D010920:Placenta / Q000201:enzymology*; D011247:Pregnancy; D012333:RNA, Messenger / Q000378:metabolism; D014599:Uterus / Q000201:enzymology
chemical_list: D012333:RNA, Messenger; C496319:NOS2 protein, human; C496314:NOS3 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; D006152:Cyclic GMP