Fig. 6

Schematic summary of the present study. Hypothalamic peptides, GnRH, kisspeptin, and NKB, were detected in primary cultures of placental cells. All of these peptides were up-regulated by estradiol (E2). GnRH expression was not regulated by kisspeptin, but was regulated by GnRH itself and NKB. Kisspeptin expression was up-regulated by GnRH and NKB. All of these neuropeptides increased hCG expression in placental cells