作者: S. Saji , E. V. Jensen , S. Nilsson , T. Rylander , M. Warner
关键词:
摘要: An obligatory role for estrogen in growth, development, and functions of the mammary gland is well established, but roles two receptors remain unclear. With use specific antibodies, it was found that both receptors, ERα ERβ, are expressed rat presence cellular distribution distinct. In prepubertal rats, detected 40% epithelial cell nuclei. This decreased to 30% at puberty continued decrease throughout pregnancy a low 5% day 14. During lactation there large induction with up 70% nuclei positive 21. Approximately 60–70% cells ERβ all stages breast development. Cells coexpressing were rare during pregnancy, proliferative phase, they represented 60% lactation, postproliferative phase. Western blot analysis sucrose gradient centrifugation confirmed this pattern expression. proliferating nuclear antigen not ERα-positive observed 3–7% ERβ-containing cells. Because more than 90% ERβ-bearing do proliferate, 55–70% dividing have neither nor clear these prerequisite estrogen-mediated proliferation.