Human placenta as a source of neuroendocrine factors.

Progress in the understanding of the physiological and pathological functions of the placenta introduced the concept that the placenta is a neuroendocrine organ, since it shows local production and release of substances analog to neurohormones. These products act as endocrine, paracrine and autocrine factors to control the secretion of other regulatory molecules, including the pituitary hormones of both mother and fetus and their placental counterparts. Furthermore, they may play a role in the regulation of maternal and fetal physiology during pregnancy, ranging from the control of placental anchoring to fetal growth and maturation, fine regulation of uterine blood flow and/or initiation of labor. All this evidence underlines the decisive contribution of the placenta to all phases of gestation, through a range of substances largely exceeding the classically known sex steroids and chorionic gonadotropin, throughout normal pregnancy as well as in the presence of gestational diseases. Copyright 2001 S. Karger AG, Basel