Onset of endogenous synthesis of epidermal growth factor in neonatal mice.
Onset of endogenous synthesis of epidermal growth factor in neonatal mice.
复制标题
新生小鼠表皮生长因子内源合成的开始。
DOI：
10.1016/0012-1606(87)90204-1
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发表时间：
1987
影响因子：
2.7
通讯作者：
Webb,CG
中科院分区：
文献类型：
--
作者：
Popliker,M;Shatz,A;Avivi,A;Ullrich,A;Schlessinger,J;Webb,CG
我们分析了小鼠胎儿和新生儿表皮生长因子（EGF）特异性mRNA的存在。从妊娠第9天到出生或新生儿早期，在胎儿、胎膜或胎盘中未发现可检测到的EGF特异性mRNA。虽然肾脏开始产生EGF特异性转录物产后两周，唾液腺开始产生可检测水平的EGF mRNA后断奶，甚至在水平远低于成人的量。关于啮齿类动物胎儿中EGF和EGF相关物质的报告未能确定该物质是母体来源还是胎儿来源。我们现在得出结论，这些胚胎中真正的EGF可能是母体来源的。我们已经进行了旨在确定EGF是否可以被运输到胎儿体内的实验。一小部分的125 I-EGF给予孕妇全身或直接进入子宫动脉到达胎儿本身。子宫和胎盘获得了高水平的标记，而羊水和卵黄囊几乎没有示踪剂。在新生儿时期，牛奶可能是EGF的生理相关来源。我们发现新生儿摄入的~（125）I-EGF被吸收进入循环，到达许多内脏器官，并最终随尿排出。先前证实的小鼠胚胎细胞类型中的EGF受体可以被α型转化生长因子或通过胎盘转运的母体EGF激活。
We have analyzed mouse fetuses and neonates for the presence of epidermal growth factor (EGF)-specific mRNA. No detectable EGF-specific mRNA was found in fetuses, fetal membranes, or placentae from Day 9 of gestation through birth or in the early neonatal period. While the kidneys begin to produce EGF specific transcripts by two weeks postpartum, the salivary glands begin to produce detectable levels of EGF mRNA only after weaning and even then at levels far below the adult amount. Reports of EGF and EGF-related material in rodent fetuses failed to determine whether this material was of maternal or fetal origin. We now conclude that authentic EGF in these embryos is probably of maternal origin. We have performed experiments designed to determine whether EGF can be transported into the fetus. A small percentage of125I-EGF administered to pregnant females either systemically or directly into the uterine arteries reached the fetus itself. The uterus and the placenta attained a high level of labeling, whereas the amniotic fluid and yolk sac were virtually devoid of the tracer. In the neonatal period, milk may be the physiologically relevant source of EGF. We have found that125I-EGF ingested by neonates was absorbed into the circulation, reached many internal organs, and was eventually excreted in the urine. Previously demonstrated EGF receptors in mouse embryonic cell types may be activated by either alpha type transforming growth factor or maternal EGF transported via the placenta.