Genes upregulated in the amnion at labour are bivalently marked by activating and repressive histone modifications.

Inflammatory genes are expressed increasingly in the foetal membranes at late gestation triggering birth. Here we have examined whether epigenetic histone modifications contribute to the upregulation of proinflammatory genes in the amnion in late pregnancy and at labour. Amnion samples were collected from early pregnancy, at term in the absence of labour and after spontaneous birth.

Inflammatory and steroid receptor gene methylation in the human amnion and decidua.

Correct timing of parturition requires inflammatory gene activation in the gestational tissues at term and repression during pregnancy. Promoter methylation at CpG dinucleotides represses gene activity; therefore, we examined the possibility that DNA methylation is involved in the regulation of labour-associated genes in human pregnancy. Amnion and decidua were collected at 11-17 weeks of gestation and at term following elective Caesarean delivery or spontaneous labour.

Molecular evidence of a (pro)renin/ (pro)renin receptor system in human intrauterine tissues in pregnancy and its association with PGHS-2.

Prorenin stimulates decidual prostaglandin (PG) production in vitro, the (pro)renin receptor ((P)RR) may mediate this action. The role of prorenin in amnion PG synthesis has not been examined, despite this being the key site of PG synthesis. To determine if (P)RR, prorenin and PGHS-2 are co-localized in gestational tissues and if expression is altered by labour, term amnion, chorion, decidua and placenta were collected during elective caesarean section or after spontaneous labour.

Optimization of a solid phase extraction procedure for prostaglandin E2, F2 alpha and their tissue metabolites.

The primary prostaglandins PGE(2) and PGF(2 alpha) are metabolized in tissues by a series of enzymatic and non-enzymatic reactions. To measure metabolic rates and individual reaction rates it is necessary to extract the parent prostaglandins and metabolites before the separation and quantification of each compound is achieved. Here we have established and optimized a solid phase extraction (SPE) procedure to recover PGE(2), PGF(2 alpha) and their six enzymatic and non-enzymatic tissue metabolites from aqueous solutions including urine, plasma and tissue homogenate.

Mechanisms regulating prostaglandin H2 synthase-2 mRNA level in the amnion and chorion during pregnancy.

Increasing prostaglandin H(2) synthase (PGHS)-2 expression in the fetal membranes is implicated in the production of prostaglandins (PGs) that stimulate labour. We have determined the activity of the PGHS-2 gene in the amnion and chorion throughout gestation and defined the contribution of transcriptional and post-transcriptional mechanisms to the increase of PGHS-2 mRNA levels. We also measured PGHS-1 mRNA abundance to assess the participation of the two isoenzymes in fetal membrane PG-production during pregnancy.

Prostaglandin H2 synthase-1 and -2 expression in guinea pig gestational tissues during late pregnancy and parturition.

Increased intrauterine prostaglandin (PG) production is crucial for the initiation of parturition. To investigate the mechanisms controlling intrauterine PG synthesis, we examined the expression of the key PG biosynthetic isoenzymes, PG-H2 synthase (PTGS)-1 and -2, in the amnion, visceral yolk sac (VYS), placenta and myo-endometrium of pregnant guinea pigs. This animal model was chosen because the hormonal milieu of pregnancy and the role of PGs in the hormonal control of parturition are similar to those in the human.

Regulation of 15-hydroxyprostaglandin dehydrogenase (PGDH) gene activity, messenger ribonucleic acid processing, and protein abundance in the human chorion in late gestation and labor.

The prostaglandin (PG)-inactivating enzyme 15-hydroxyprostaglandin dehydrogenase (PGDH) is highly expressed in the chorion leave. To assess the involvement of PGDH in the regulation of intrauterine PG levels, we have determined the mechanisms that control chorionic PGDH expression in women at term and preterm labor. PGDH gene activity decreased at term and during normal labor.

The control of prostaglandin endoperoxide H-Synthase-2 expression in the human chorion laeve at term.

Objective: Prostaglandin endoperoxide H synthase-2 (PGHS-2), the key enzyme of prostaglandin biosynthesis in gestational tissues, is expressed in the chorion laeve at term. We have determined the mechanisms that control the level of PGHS-2 mRNA in the chorion membrane in order to assess the significance of chorion-derived prostaglandins in term labor.

Methods: Chorion membranes were collected after elective cesarean delivery (CD, n = 21) and after spontaneous labor (SL, n = 20) at term.

The in vivo control of prostaglandin H synthase-2 messenger ribonucleic acid expression in the human amnion at parturition.

Prostaglandin H synthase-2 (PGHS-2) activity and mRNA rise in the human amnion at late gestation, contributing to the increase in intrauterine PG production crucial for labor and delivery. In the present investigation we have determined the mechanism that controls amniotic PGHS-2 mRNA levels in vivo at term parturition. Amnion membranes were collected after elective cesarean section (n = 20), and after spontaneous labor (n = 20).