title: Serum levels of a placental protein during gestation in the baboon.
abstract: A placental specific protein (Sp-1) isolated from human placentas was used to establish a radioimmunoassay for measurement of a baboon protein in the sera of pregnant baboons. No reaction was observed with any known pituitary or placental hormone in this assay system. Levels of Sp-1 were detected at 17 to 18 days of gestation and reached high levels by the end of the first trimester of pregnancy. A slow increase in serum levels continued thereafter until parturition. Disappearance of Sp-1 post partum was very slow and required 26 to 34 days to become undetectable in the serum. No function or role of Sp-1 in pregnancy has been suggested, but possible use of its measurement for detecting abnormal placental function deserves investigation.
mesh_terms: D000818:Animals; D001798:Blood Proteins / Q000032:analysis; D006063:Chorionic Gonadotropin / Q000032:analysis; D005260:Female; D005865:Gestational Age; D010215:Papio / Q000097:blood*; D010920:Placenta / Q000032:analysis*; D010928:Placental Lactogen / Q000032:analysis; D049590:Postpartum Period; D011247:Pregnancy; D011270:Pregnancy, Animal; D011506:Proteins / Q000032:analysis* / Q000145:classification; D011863:Radioimmunoassay / Q000379:methods
chemical_list: D001798:Blood Proteins; D006063:Chorionic Gonadotropin; D011506:Proteins; D010928:Placental Lactogen