The initiation of parturition in most mammalian species is regulated by steroid hormones. Because progesterone (P4) concentrations in maternal plasma of primates do not decrease before parturition, paracrine changes of steroids within intrauterine tissues are considered important. A possible relationship between steroids (estradiol (E2) and P4 in decidua, glucocorticoids in amnion), prostaglandins (PG) and oxytocin has been proposed. We therefore collected amnion and decidua from rhesus monkeys in the third trimester of gestation (n=3) at cesarean section. Tissues were collected under sterile conditions and amnion was dispersed according to the methods of Olson et al (JCEM 57:694, 1983) using pseudo-amniotic fluid as the culture media. Decidual cells were isolated according to the methods routinely used in the Cell Culture Core at ORPRC. Decidual cells were introduced into wells of a 24- well plate and grown to confluence. After cells reached confluence, the wells were divided into four treatment groups of six wells and were incubated with different steroid combinations 1) E2 (0.01 nM) and P4 (0.1 nM); 2) E2 only (0.01 nM); 3) P4 only (0.1 nM); and 4) no steroids. After a 24 hour incubation, oxytocin was added to 4 wells in each group, the other 2 received no oxytocin and were considered steroid controls. Media was collected after 3 hours. PGF2` was measured by EIA (Cayman Chemical). Significant amounts of PGF2` was measured in each well; however, there were no significant differences between steroid treatment or addition of oxytocin. Analysis of amnion cultures for changes in concentrations of PGE2 relative to dexamethasone and oxytocin treatment are ongoing. Funds allocated to this preliminary project were to be used to measure prostaglandin concentrations in media from cultures previously set up with tissues collected from animals on other projects.
Showing the most recent 10 out of 492 publications
