Ontogenesis of testicular function in humans.

The two major functions of the testis, steroidogenesis and gametogenesis, take place during fetal life. These two functions have been extensively studied in rodents and adult humans. However, their onset during fetal life is poorly documented in humans. In the first part of this work we presented both our experimental data and some data of literature concerning the development of the human fetal testis. In the second part of this article, using the organ culture system we previously developed, we have investigated the regulations or perturbations of fetal testis development both in rodent and human models. Our findings provide important insight into the potential role of exposure to environmental pollutants (physical factors, in particular ionizing radiation, cadmium and endocrine disruptors such as phthalates) during fetal testicular development and their potential deleterious effects on male fertility in adulthood. Our results highlight the specificity of the human model compared with rodent models.