Novel multialveolar epithelial structures from rabbit mammary gland that synthesize milk specific fatty acids in response to prolactin

Summary Multialveolar mammary epithelial structures have been prepared from rabbit mammary gland by treating the tissue with collagenase plus hyaluronidase. These structures synthesize milk specific fatty acids when cultured with physiological concentrations (0.05 μg/ml) of prolactin in the presence of insulin and corticosterone. They have many of the advantages but few of the disadvantages of either mammary explains or primary cells in culture. For example, they are easily prepared in large numbers and respond to prolactin in culture even in the absence or other tissue extracts. Because their level of organization is intermediate between that of explants and single cells, they provide a complementary system for studies on mammary differentiation. This work was supported by grants from the Agricultural Research Council of Great Britain and the Royal Society to R. R. Dils, by U.S. Public Health Service Grant CA-16392, and an American Cancer Society-Eleanor Roosevelt International Cancer Fellowship to H. L. Hosick. Prolactin was a gift from the Endocrinology Study Section, National Institutes of Health, Bethesda, MD.