HUMAN PLACENTA AND FETAL MEMBRANES CONTAIN PEPTIDE YY1-36 AND PEPTIDEYY3-36

Extracts of human term amniotic, placental, and chorion/decidua tissue contained, respectively, 4.36+/-2.79 (pmol/g wet wt; mean+/-S.E.M.; n =5), 2.78+/-0.5 (n=5) and 0.68+/-0.68 (n=5) peptide YY (PYY)-like immu noreactivity. Using a specific PW antiserum, gel filtration chromatogr aphy and reverse-phase high performance liquid chromatography (HLPC), amniotic, placental and fetal intestinal tissue extracts were demonstr ated to contain PYY-like immunoreactivity consisting of equal amounts of PYY1-36 and PYY3-36. The presence oi pancreatic polypeptide was not detected in any of the extracts. Positive immunohistochemical stainin g for PW was seen in extravillous trophoblasts in the decidual septa a nd fetal membranes, the syncytiotrophoblast and cytotrophoblasts, amni otic epithelial cells and in maternal decidual stromal cells. Positive staining for PYY was found at the earliest date examined (9.5 weeks) and remained present throughout pregnancy to term. PYY1-36 and PYY3-36 may play important roles in human pregnancy, acting via endocrine or paracrine mechanisms.