Newbold R R, Hanson R B, Jefferson W N
Environmental Toxicology Program, Division of Intramural Research, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, USA.
Biol Reprod. 1997 May;56(5):1147-57. doi: 10.1095/biolreprod56.5.1147.
Lactoferrin (LF) was mapped during organogenesis of the murine reproductive tract, starting on fetal Day 12, as a marker of estrogen responsiveness. To induce LF expression, pregnant outbred CD-1 mice were injected s.c. with diethylstilbestrol (DES; 100 microg/kg maternal body weight), and fetal genital tract tissues were removed; neonatal and immature mice received s.c. injections of DES (2 microg/pup per day). Corn oil-treated and untreated mice at corresponding ages provided the controls. Immunocytochemical techniques using a polyclonal antibody showed no detectable LF in control genital tract tissues until late gestation. However, after DES treatment, LF was localized in uterine epithelial cells as early as fetal Day 14; the intensity of LF staining increased with age and number of DES treatments. Control uterine tissues responded to the rise of circulating estrogens at parturition (fetal Day 19) by producing LF, although the magnitude of response was lower than that of DES-treated tissues. Uterine tissue homogenates from control and DES mice were analyzed by SDS-PAGE and Western blots, verifying the protein to be LF. Isolation of mRNA and Northern blot analysis further showed that LF mRNA was present in the developing Mullerian duct and that DES stimulated early induction of the LF gene. The early appearance of LF suggests that it may play an important role in the hormonal regulation of growth and differentiation of developing uterine tissues.
乳铁蛋白（LF）在小鼠生殖道器官发生过程中被定位，从胎儿第12天开始，作为雌激素反应性的标志物。为诱导LF表达，对怀孕的远交群CD-1小鼠皮下注射己烯雌酚（DES；100微克/千克母体体重），并取出胎儿生殖道组织；新生小鼠和未成熟小鼠皮下注射DES（2微克/只/天）。玉米油处理和未处理的相应年龄小鼠作为对照。使用多克隆抗体的免疫细胞化学技术显示，在对照生殖道组织中直到妊娠晚期都未检测到LF。然而，DES处理后，LF最早在胎儿第14天就定位于子宫上皮细胞；LF染色强度随年龄和DES处理次数增加。对照子宫组织在分娩时（胎儿第19天）对循环雌激素的升高产生反应，产生LF，尽管反应程度低于DES处理的组织。对对照和DES处理小鼠的子宫组织匀浆进行SDS-PAGE和蛋白质印迹分析，证实该蛋白为LF。mRNA的分离和Northern印迹分析进一步表明，LF mRNA存在于发育中的苗勒管中，并且DES刺激了LF基因的早期诱导。LF的早期出现表明它可能在发育中的子宫组织生长和分化的激素调节中起重要作用。
