This project is designed to understand the role of hormones and growth factors in normal mammary gland development and differentiation. We wish to understand how milk-protein production is controlled by various hormones. Studies include: 1) purification of alpha-lactalbumin from mouse mammary glands and preparation and characterization of an antibody, 2) examination of the role of thyroid hormones and adrenal sterioids in synthesis and secretion of milk proteins in organ culture, 3) examination of the role of epidermal growth factor and mammary gland-derived growth factors in lobulo-alveolar development of the immature mouse mammary gland.