title: The proliferative behavior of the human adult mammary epithelium.
abstract: Normal, human, resting, breast tissue was cultured in the defined culture medium 199 with and without insulin. DNA synthesis was assessed by use of autoradiography. A labeling index (LI) showed a different sensitivity in terms of DNA synthesis in the three basic segments of the mammary tree: intralobular ductules, terminal ducts and large ducts. The LI increased significantly after six hours in the terminal ducts, both in the basic unenriched 199 medium and in the presence of 1 microgram/ml insulin. Cumulative LIs were representative of the interlobular ducts, the most active part of breast epithelium.
mesh_terms: D000293:Adolescent; D000328:Adult; D001345:Autoradiography; D001940:Breast / Q000166:cytology* / Q000378:metabolism; D002455:Cell Division; D004247:DNA / Q000096:biosynthesis; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism; D005260:Female; D006801:Humans; D007328:Insulin / Q000494:pharmacology; D008875:Middle Aged; D009924:Organ Culture Techniques
chemical_list: D007328:Insulin; D004247:DNA