[Cytochemical localization of an important adenyl-cyclase activity in Anuran amphibian embryo chordo-mesoderm by electron microscopy; its possible relations with the migration of primordial germ cells (author's transl)].

Chordo-mesoderm of Anura Amphibia embryos was investigated by electron microscopy and a cytochemical method was used to study the localization of adenyl-cyclase activity, in this part of embryo. It seem that, in Anura, at a given stage of development, there is some adenyl-cyclase activity, and, consequently, some liberation of AMPc. Pleurodeles waltlii (Urodela Amphibia) appears to be devoid of this adenyl-cyclase activity. AMPc could be the substance provided by chordo-mesoderm attracting germinal cells.