title: Autoradiographic localization of 3H-ORG 2058, a synthetic progestin, in the mammary glands of the baboon.
abstract: The uptake and retention of a radiolabeled synthetic progestin ORG 2058 by the mammary glands were examined in the baboon. Four estrogen-primed baboons were injected intravenously with 2.5 micrograms/kg body weight of 3H-ORG 2058. One animal received an additional injection of 2.5 mg/kg body weight of unlabeled progesterone. One hour after the injections, the animals were killed and the mammary glands were removed and processed for autoradiography. Only 13.4% of the alveolar secretory cells studied demonstrated nuclear uptake and retention of the radiolabeled steroid, while 60% of the alveoli demonstrated at least 1 labeled cell per cross-section. The fibroblasts in the interlobular connective tissue and most of the cells lining the interlobular ducts were labeled; however, no cells in the intralobular connective tissue were labeled. These observations seem to indicate that all alveolar secretory cells do not contain progesterone receptors in the normal mammary gland.
mesh_terms: D000818:Animals; D001345:Autoradiography; D002369:Castration; D005260:Female; D008321:Mammary Glands, Animal / Q000378:metabolism*; D010215:Papio; D011282:Pregnenediones / Q000378:metabolism*; D014316:Tritium
chemical_list: D011282:Pregnenediones; D014316:Tritium; C020175:16 alpha-ethyl-21-hydroxy-19-nor-4-pregnene-3,20-dione