The role of corticotropin-releasing hormone receptors in placenta and fetal membranes during human pregnancy

Corticotropin-releasing hormone (CRH) is a 41 amino acid polypeptide that e xerts a wide spectrum of hypothalamic and extrahypothalamic functions. More over, the placenta and other intrauterine tissues produce and secrete immun oreactive CRH. It has been demonstrated that placental CRH is secreted into the maternal circulation in large amounts during the third trimester of hu man pregnancy and may play an important role in the onset of labor. CRH exe rts a number of functions within the intratuterine environment like inducti on of prostaglandin production and maintenance of the placental blood flow. Here we present an overview of current knowledge about the CRH receptor su btypes and their signaling properties within the fetoplacental unit. (C) 20 01 Academic Press.