
<ArticleTitle>Increase of <prot>endothelial nitric oxide synthase</prot> and <prot>endothelin-1</prot> mRNA expression in human placenta during gestation.</ArticleTitle>
<AbstractText>OBJECTIVE: To investigate the maturation of the paracrine system's <prot>endothelial nitric oxide synthase</prot> (<prot>eNOS</prot>), <prot>inducible NOS</prot> (<prot>iNOS</prot>), <prot>endothelin-1</prot> (<prot>ET-1</prot>) and <prot>adrenomedullin</prot> (<prot>AM</prot>) in human placenta during the 2nd and 3rd trimester of pregnancy. STUDY DESIGN: Placental tissue from 14 healthy women with normal pregnancy and from 13 patients giving birth to premature infants following premature labor was obtained. Messenger RNA expression was determined using quantitative TaqMan real-time PCR. RESULTS: Placental <prot>eNOS</prot>/<prot>GAPDH</prot> and <prot>ET-1</prot>/<prot>GAPDH</prot> mRNA expression significantly increased as a function of gestational age (r=0.63, P&#60;0.001 and r=0.53, P=0.007, respectively). There was no change in gene expression of neither <prot>iNOS</prot> nor <prot>AM</prot> mRNA/<prot>GAPDH</prot> during gestation (r=0.02, P=0.75 and r=0.001, P=0.99, respectively). CONCLUSION: There is a maturation of <prot>eNOS</prot> and <prot>ET-1</prot> in human placenta with gestation reflecting developmental changes of important paracrine endothelial and trophoblastic regulators. <prot>AM</prot> and <prot>iNOS</prot> show no maturation during pregnancy.</AbstractText>
