ROLE OF THE OVIDUCT DURING EARLY EMBRYOGENESIS

A large number of studies suggests that the oviduct exerts an importan t role in early embryonic development but its nature is far from being elucidated. At present embryotrophic action seems to be based upon th e interaction between the embryo and various groups of molecules. Thes e include (a) specific proteins secreted by the epithelium of restrict ed oviduct regions; (b) growth factors normally present also in other districts of the organism, whose ligand and receptors genes are often expressed both in the oviduct and in the embryo, (c) various metabolit es, such as glucose, oxygen and free radicals scavengers, which determ ine the environment where the developmental potential of fertilized eg gs can be fully expressed. These groups of substances will be examined in some details giving particular emphasis to most recent acquisition s.