Steroid-Membrane-Adenylate Cyclase Interactions during Xenopus laevis Oocyte Meiosis Reinitiation: A New Mechanism of Steroid Hormone Action

: Progesterone acts physiologically on Xenopus laevis oocyte meiosis reinitiation in interacting with plasma membrane. Hormonal studies indicate a specific "receptor-like" structure. The involvement of membrane adenylate cyclase activity which is selectively decreased by progesterone is described in intact oocytes as well as in a cell-free membrane containing system. The participation of Ca2+ changes and of phospholipid components of membrane is analyzed. We discuss the possibility that the progesterone-oocyte system is a model for understanding other steroid hormone activities in other target cells.