Insulin regulates placental lactogen and estradiol secretion by cultured human term trophoblast.

We have described a human term trophoblast cell culture system which synthesizes hormones de novo from their precursors. In the present report we utilized this monolayer system to show that insulin produced a dose-dependent stimulation of hPL secretion, with a significant effect at 10(-10) M insulin. At 10(-9) M concentration, insulin also inhibited estradiol secretion by the cultured trophoblast. We conclude that insulin regulates secretion of estradiol and placental lactogen by cultured human term trophoblast.