O-89:Expression Of MelatoninergicReceptors In Human Placenta AndChoriocarcinoma Cells



Background: Melatonin concentrations increase in maternal blood during pregnancy, reaching a maximum at term. Moreover, experimental data suggest a possible influence of melatonin on placental function and fetal development in humans. To date, the expression and role of melatonin receptors in human placenta choriocarcinoma cell lines and in human term placental tissues remain to be elucidated. METHODS AND Materials and Result: Results from RT–PCR, western blotting and confocal microscopy demonstrated that the MT1, MT2 and RORa1 melatonin receptors are expressed in the human term placental tissues and in choriocarcinoma cell lines JEG-3 and BeWo (both in vitro models of human trophoblast). Furthermore, enzyme-linked immunosorbent assay showed that 6-chloromelatonin (a melatonin agonist) inhibits, in a dosedependent manner, forskolin-stimulated hCG- β secretion in JEG-3 (p