[The problem of testosterone secretion by the chick embryo testis: new research].

The aim of this study was to determine whether the chick embryo testis was able to convert dehydroepiandrosterone and androstenedione into testosterone. Testes from 17-19 day old chick embryos were cultured in vitro in the presence of tritiated dehydroepiandrosterone or androstenedione of high specific activity, and the radioactive testosterone formed was isolated by thin-layer chromatography and identified by recrystallization to constant specific activity. Parallel experiments with mouse embryo testes showed that these methods were valid. However, since specific activity with chick embryo testes was very low and could not be brought to constancy, testosterone could not be identified with these testes. It is concluded that the 17-19 day old chick embryo testis cannot form testosterone from either dehydroepiandrosterone or androstenedione. This conclusion is in keeping with the absence of a physiological role for testosterone in the male chick embryo.