title: Immunocytochemistry of human chorionic gonadotropin in human chorionic villi.
abstract: The immunocytochemical localization of human chorionic gonadotropin was investigated in chorionic villi from the seventh to twelfth week of gestation. By the light microscopic peroxidase-antiperoxidase technique, positive reactions of human chorionic gonadotropin were found exclusively in the syncytiotrophoblast. Immunoelectron microscopy by means of the protein A-gold technique reveals localization of the immunoreactive gold particles in two kinds of membrane-bound granular inclusions in this cell; one type is granules of 200 to 300 nm in diameter with moderate electron density and the other is large electron-dense bodies of 500 to 1000 nm. The former seems to be Golgi-derived secretory granules that play a role in the release of human chorionic gonadotropin from the syncytiotrophoblast. Although the origin of the latter is still uncertain, a certain amount of this hormone might be stored or treated by lysosomal digestion in the large bodies during these stages.
mesh_terms: D000937:Antigen-Antibody Reactions; D006063:Chorionic Gonadotropin / Q000032:analysis*; D002824:Chorionic Villi / Q000032:analysis* / Q000648:ultrastructure; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008854:Microscopy, Electron; D011247:Pregnancy; D011261:Pregnancy Trimester, First
chemical_list: D006063:Chorionic Gonadotropin