Insulin-like growth factor receptor in fetal lamb liver: characterization and developmental changes.
Insulin-like growth factor receptor in fetal lamb liver: characterization and developmental changes.
复制标题
胎儿羔羊肝脏中的胰岛素样生长因子受体：特征和发育变化。
作者：
P. Owens;M. Waters;G. Thorburn;M. Brinsmead
增殖刺激活性（MSA）是一种胰岛素样生长因子（IGF）（大鼠IGF II），可与胎羊许多组织的提取物结合。我们现在报告的存在下，高浓度的糖蛋白受体具有高亲和力的MSA-II的微粒体从胎羊肝脏制备。放射性标记的MSA-II的结合被IGF抑制，但不被胰岛素、人和绵羊GH、绵羊PRL、绵羊胎盘催乳素和小鼠表皮生长因子抑制。人IGF II、人IGF I和MSA-II与[125 I]MSA-II竞争结合该受体的相对效力为100：17：3.5（重量）。结合是pH、时间和温度依赖性的。Triton X-100可溶性受体的凝胶渗透色谱法表明流体动力学半径为6.8 nm。特异性结合从妊娠中期到晚期增加，并且与受体的亲和力和浓度的变化相关。受体浓度从7.95 +/- 3.94 pmol/mg（平均值+/- SE），妊娠78天至134-140天为15.8 +/- 4.3 pmol/mg（P小于0.05），而受体亲和力在此期间从1.14 +/- 0.34 × 10（9）升/摩尔降低至0.63 +/- 0.14 × 10（9）升/摩尔（P小于0.05）。胎儿羊肝中存在非常高浓度的IGF受体，表明该器官可能是胎儿生命中IGF作用的主要靶点。随着胎龄的增加，对IGF II具有优先特异性的IGF受体的浓度可能起到增加胎羊肝脏对IGF II刺激的反应性的作用，从而补偿在出生附近发生的这种生长因子的血浆浓度的下降。
Multiplication-stimulating activity (MSA), an insulin-like growth factor (IGF) (rat IGF II), binds to extracts of many tissues from fetal lambs. We now report the presence of high concentrations of a glycoprotein receptor with a high affinity for MSA-II in microsomes prepared from fetal lamb liver. The binding of radiolabeled MSA-II is inhibited by IGF but not by insulin, human, and ovine GH, ovine PRL, ovine placental lactogen, and mouse epidermal growth factor. The relative potencies of human IGF II, human IGF I, and MSA-II in competing with [125I]MSA-II for binding to this receptor are 100:17:3.5 by weight. Binding is pH, time, and temperature dependent. Gel permeation chromatography of the Triton X-100 soluble receptor indicates a hydrodynamic radius of 6.8 nm. Specific binding increases from mid- to late gestation and is associated with changes in both the affinity and concentration of receptors. Receptor concentration increases from 7.95 +/- 3.94 pmol/mg (mean +/- SE) at 78 days gestation to 15.8 +/- 4.3 pmol/mg at 134-140 days (P less than 0.05), whereas receptor affinity decreases from 1.14 +/- 0.34 X 10(9) liter/mol to 0.63 +/- 0.14 X 10(9) liter/mol over this period (P less than 0.05). The presence of very high concentrations of an IGF receptor in fetal lamb liver suggest that this organ may be a major target for IGF action in fetal life. The increase with advancing gestational age of the concentration of IGF receptors which have preferential specificity for IGF II may function to increase the responsiveness of the fetal lamb liver to IGF II stimulation and so compensate for the decline in plasma concentrations of this growth factor which occur near birth.
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影响因子：
4.8
作者：
D. Klapper;M. Svoboda;J. J. Wyk-J.
通讯作者：
D. Klapper;M. Svoboda;J. J. Wyk-J.
大鼠碱性生长调节素的分离和部分序列分析。
影响因子：
4.8
作者：
Rubin,JS;Mariz,I;Jacobs,JW;Daughaday,WH;Bradshaw,RA
通讯作者：
Bradshaw,RA
胰岛素受体单克隆抗体与胰岛素样生长因子受体的相互作用。
影响因子：
4.8
作者：
Roth,RA;Maddux,B;Wong,KY;Styne,DM;VanVliet,G;Humbel,RE;Goldfine,ID
通讯作者：
Goldfine,ID
胎羊血清生长调节素 C 浓度在妊娠期间显着增加。
DOI：
10.1677/joe.0.0960269
发表时间：
1983
期刊：
The Journal of endocrinology
影响因子：
--
作者：
Handwerger,S;D'Ercole,AJ;Underwood,LE;Gluckman,P;Liggins,GC
通讯作者：
Liggins,GC