Transport of 125I-EGF into milk and effect of sialoadenectomy on milk EGF in mice.
Transport of 125I-EGF into milk and effect of sialoadenectomy on milk EGF in mice.
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125I-EGF 进入乳汁的转运以及唾液腺切除术对小鼠乳汁 EGF 的影响。
DOI：
10.1152/ajpendo.1984.247.3.e349
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发表时间：
1984
期刊：
影响因子：
--
通讯作者：
Barka,T
中科院分区：
文献类型：
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作者：
Gresik,EW;vanderNoen,H;Barka,T
表皮生长因子(EGF)(尿激素酮)在小鼠和人类的乳汁中含量很高。牛奶中EGF的来源尚不清楚。在静脉注射示踪剂量的~(125)I-EGF后2~6h，采集哺乳期小鼠的乳汁样本。牛奶中含有较高水平的放射性，其中35-46%由三氯乙酸-磷钨酸(TCA-PTA)沉淀，26%由特异性抗小鼠EGF抗血清沉淀。牛奶中的部分放射性是从Bio-Gel P-10柱上洗脱出来的，洗脱点是纯标准的125I-EGF。这些数据表明，哺乳期小鼠的乳腺能够隔离和转运~(125)I-EGF进入乳汁。注射超过1000倍的未标记EGF，不会导致注射125I-EGF的小鼠乳样中TCA-PTA可沉淀的放射性减少。当给予小鼠10微克未标记的EGF，并在4小时后收集乳汁时，与对照组相比，乳汁中的EGF水平增加了一倍。添加EGF对牛乳中的乳糖和蛋白质浓度没有影响，十二烷基硫酸钠-聚丙烯酰胺凝胶电泳法显示乳中主要蛋白质没有定性或定量的变化。与对照组相比，6个月前切除唾液腺的哺乳期小鼠的乳汁中EGF含量减少了约50%。注射~(125)I-EGF后，在乳腺、颌下腺和胃中也发现了较高浓度的放射性。然而，在后一种器官中，95-96%的放射性存在于酸可溶部分。
Epidermal growth factor (EGF) (urogastrone) is found in high concentrations in mouse and human milk. The origin of milk EGF is unknown. Milk samples were collected from lactating mice 2-6 h after the intravenous administration of a tracer dose of 125I-labeled EGF. The milk contained relatively high levels of radioactivity of which 35–46% was precipitated by trichloroacetic acid-phosphotungstic acid (TCA-PTA) and 26% by a specific antimouse EGF antiserum. Part of the radioactivity in milk was eluted from a Bio-Gel P-10 column at the point at which pure standard 125I-EGF was eluted. These data indicate that the mammary gland of the lactating mouse is capable of sequestering and transporting 125I-EGF into milk. Administration of a thousand-fold excess of unlabeled EGF caused no reduction in TCA-PTA-precipitable radioactivity in milk samples of mice given 125I-EGF. When mice were given 10 micrograms of unlabeled EGF and milk was collected 4 h later, compared with controls the EGF level in milk was doubled. Administration of EGF had no effect on lactose and protein concentrations in the milk, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed no qualitative or quantitative changes in the major milk proteins. Milk collected from lactating mice that were sialoadenectomized 6 mo earlier contained about 50% less EGF compared with controls. After the administration of 125I-EGF high concentrations of radioactivity were also found in the mammary and submandibular glands and in the stomach. In the latter organs, however, 95–96% of the radioactivity was in the acid-soluble fraction.(ABSTRACT TRUNCATED AT 250 WORDS)