NUCLEAR MATURATION INHIBITORS IN BUFO-ARENARUM OOCYTES

In Bufo arenarum, as in other amphibian species, nuclear maturation -c haracterized by germinal vesicle breakdown (GVBD) and meiosis resumpti on- is induced by progesterone. Seasonal variations in the sensitivity to progesterone were observed in Bufo arenarum oocytes. The gonadotro pin FSH and drugs such as dbcAMP and xanthine did not affect nuclear m aturation per se, although they acted as negative modulators of proges terone-induced nuclear maturation. Similar results to FSH in nuclear m aturation were obtained with 17 beta-estradiol.