The hormonal induction of maturation in amphibian oocytes.

The maturation of the amphibian oocyte has been analyzed. Progesterone as well as organomercurials, lanthanum chloride and propranolol rapidly induce maturation. These chemicals are active only is applied on the cell surface. The mechanism seems to be an induction of the migration of Ca2+ from the cell membrane to the cytoplasm. K + may also play a role. Progesterone induced maturation involves synthesis of histone and histone kinase as well as several biologically active but chemically unidentified factors. cAMP does not seem to be directly involved, whereas protein phosphorylation is so.