ROLE OF THE OVIDUCT DURING EARLY EMBRYOGENESIS

A large number of studies suggests that the oviduct exerts an important role in early embryonic development but its nature is far from being elucidated. At present embryotrophic action seems to be based upon the interaction between the embryo and various groups of molecules. These include (a) specific proteins secreted by the epithelium of restricted 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 metabolites, such as glucose, oxygen and free radicals scavengers, which determine the environment where the developmental potential of fertilized eggs can be fully expressed. These groups of substances will be examined in some details giving particular emphasis to most recent acquisitions.