Studies, involving the development of methods for studying the regulation of adrenal steroidogenesis in the mallard duck embryo, will be supported. The studies will ultimately contribute to our understanding of the regulatory mechanisms concerned with the overall control of the adrenal steroidogenic function. The experimental system will be the developing adrenal gland in the mallard duck embryo. Histochemical and immunocytochemical analysis, coupled with ultrastructure analysis, are necessary to identify the products and identify the distribution of nerve tissue. Tissue-superfusion technique and radioimmunoassay are needed for defining the functional characteristics of the developing tissue. The approach will allow the investigators to establish when the developing anlage becomes sensitive to corticotropin and angiotensin II.
