Progesterone receptors in hypothalamus and pituitary during the embryonic development of the chick: regulation by sex steroid hormones.

The distribution of progesterone receptor (PR) was immunohistochemically investigated in the hypothalamus and pituitary of the chick embryo (4-14 days of incubation) using an antibody against PR. PR first appears in the diencephalic floor on day 4 of incubation. From day 7 a distribution similar to that found in adult animals is observed.

Early sex differences in hormonal potentialities of gonads from quail embryos with a sex-linked pigmentation marker: an in vitro radioimmunoassay study.

Quail embryos with a sex-linked eye pigmentation marker allowing sex identification at autopsy provided a biological model for radioimmunoassay of sex steroids in embryonic quail gonads at a very early stage (51/2 and 61/2 days). The purpose was to demonstrate a sex difference in hormonal potentialities of the gonads before any morphological indication of sexual differentiation. Evidence of early steroidogenesis by undifferentiated gonads could be obtained: estrogen synthesis characterized female gonads, while testosterone was produced by the gonads of both sexes.

[Value of amineptin in the treatment of different depressive states. Apropos of 112 cases treated as part of a national multi-centric study].

Amineptine is a new tricyclic compound with a grafted long aliphatic chain active on Dopamine synaptic release and as such more desinhibitor, safer and short acting. The study was coordinated by a national and 13 local counsellors. It was an open study.

Early Morphogenesis of Chick Gonad in the Absence of Mesonephros: (morphogenesis/gonad/mesonephric agenesis).

The development of the gonads in male and female chick embryos with induced unilateral mesonephric agenesis was studied using grafting, histoenzymology, and electron microscopy. As in embryos with a mesonephros, proliferation of the coelomic epithelium and its interaction with mesenchymal cells to form the medullary cords take place in the amesonephric gonads. In a similar manner, gonadal sexual differentiation and the differentiation of steroidogenic tissue, detectable by the presence of Δ5-3β-hydroxysteroid dehydrogenase, do not appear to be affected by the absence of an organized mesonephros.