OBJECTIVE: The purpose of this study was to characterize placental expression of the prostaglandin synthase enzymes cyclooxygenase (COX) -1 and -2 and prostaglandin dehydrogenase (PGDH, a degrading enzyme). STUDY DESIGN: Forty-one women between 20 and 37 weeks' gestation and 39 matched term controls with either spontaneous labor or premature rupture of membranes were enrolled in a prospective case-control study. The relative amounts of placental RNAs at delivery were determined using real-time polymerase chain reaction (PCR). RESULTS: Placental COX-1 RNA decreased with advancing gestational age at delivery (R(2) = 0.13, P = .001), and increased by 43% when chorioamnionitis was present (P = .006). Among patients presenting at term, oxytocin use was associated with 30% lower expression of COX-1 (P = .01). COX-2 and PGDH were not associated with these variables. CONCLUSION: Placental COX-1 RNA at delivery decreases with advancing gestational age and with oxytocin use at term. Thus, expression of placental COX-1 is not constitutive. Placental expression of COX-2 and PGDH do not correlate with gestational age, chorioamnionitis, or oxytocin use.
OBJECTIVE: The purpose of this study was to characterize placental expression of the prostaglandin synthase enzymes cyclooxygenase (COX) -1 and -2 and prostaglandin dehydrogenase (PGDH, a degrading enzyme). STUDY DESIGN: Forty-one women between 20 and 37 weeks' gestation and 39 matched term controls with either spontaneous labor or premature rupture of membranes were enrolled in a prospective case-control study. The relative amounts of placental RNAs at delivery were determined using real-time polymerase chain reaction (PCR). RESULTS: Placental COX-1 RNA decreased with advancing gestational age at delivery (R(2) = 0.13, P = .001), and increased by 43% when chorioamnionitis was present (P = .006). Among patients presenting at term, oxytocin use was associated with 30% lower expression of COX-1 (P = .01). COX-2 and PGDH were not associated with these variables. CONCLUSION: Placental COX-1 RNA at delivery decreases with advancing gestational age and with oxytocin use at term. Thus, expression of placental COX-1 is not constitutive. Placental expression of COX-2 and PGDH do not correlate with gestational age, chorioamnionitis, or oxytocin use.
Authors: Roberto Romero; Shali Mazaki-Tovi; Edi Vaisbuch; Juan Pedro Kusanovic; Tinnakorn Chaiworapongsa; Ricardo Gomez; Jyh Kae Nien; Bo Hyun Yoon; Moshe Mazor; Jingqin Luo; David Banks; John Ryals; Chris Beecher Journal: J Matern Fetal Neonatal Med Date: 2010-05-26