Fenton S E, Sheffield L G
Endocrinology-Reproductive Physiology Program, University of Wisconsin, Madison 53706.
Biochem Biophys Res Commun. 1991 Dec 31;181(3):1063-9. doi: 10.1016/0006-291x(91)92045-l.
Epidermal growth factor (EGF) is known to stimulate mammary epithelial proliferation, has been identified in milk and is expressed in lactating mammary epithelia. This study examined hormonal control of EGF mRNA in mammary glands of mice. Prepro-EGF mRNA (4.7 kb) was detected during lactation (and increased significantly during this period), whereas a smaller EGF-like RNA (.5 kb) was at highest levels in mammary glands of virgin and pregnant mice. The 4.7 kb RNA was polyadenylated, whereas .5 kb RNA was not. In mammary gland organ cultures from steroid-primed mice, the combinations of insulin + hydrocortisone and insulin + prolactin + hydrocortisone increased both prepro-EGF and beta-casein mRNA expression. When hydrocortisone was present there was a decrease in mammary gland content of EGF-like RNA (.5 kb band). We conclude that prepro-EGF mRNA expression in mouse mammary tissue is under the control of the lactogenic hormones prolactin and hydrocortisone.
已知表皮生长因子（EGF）可刺激乳腺上皮细胞增殖，已在乳汁中被鉴定出，且在泌乳期乳腺上皮中表达。本研究检测了小鼠乳腺中EGF mRNA的激素调控情况。在泌乳期检测到前体-EGF mRNA（4.7 kb）（且在此期间显著增加），而较小的类EGF RNA（0.5 kb）在处女鼠和妊娠小鼠的乳腺中水平最高。4.7 kb的RNA是多聚腺苷酸化的，而0.5 kb的RNA不是。在来自用类固醇预处理小鼠的乳腺器官培养物中，胰岛素+氢化可的松以及胰岛素+催乳素+氢化可的松的组合增加了前体-EGF和β-酪蛋白mRNA的表达。当存在氢化可的松时，类EGF RNA（0.5 kb条带）的乳腺含量降低。我们得出结论，小鼠乳腺组织中前体-EGF mRNA的表达受泌乳激素催乳素和氢化可的松的调控。
