Identification and Characterization of Insulin Receptors in Basolateral Membranes of Dog Intestinal Mucosa
Identification and Characterization of Insulin Receptors in Basolateral Membranes of Dog Intestinal Mucosa
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狗肠粘膜基底外侧膜中胰岛素受体的鉴定和表征
DOI：
10.2337/diab.36.10.1124
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发表时间：
1987
期刊：
影响因子：
7.7
通讯作者：
J. Gavin
中科院分区：
文献类型：
--
作者：
R. Gingerich;W. Gilbert;P. Comens;J. Gavin
关于小肠粘膜衬里底物运输和代谢的激素调节知之甚少。由于胰岛素在其他组织中通过与其受体结合来调节这些功能，我们研究了用山梨糖醇密度离心制备的犬小肠基底外膜（BLM）和刷状边界膜（BBM）中胰岛素受体的存在。使用A14-[125l]碘胰岛素研究BLM中特异性胰岛素受体的结合和结构特征。通过对BLM受体的分析，鉴定出高亲和力（Kd 88 pM）和低容量（0.4 pmol/mg蛋白）以及低亲和力（Kd 36 nM）和高容量（4.7 pmol/mg蛋白）的结合位点。结合是时间、温度和pH依赖的，在未标记胰岛素存在的情况下，125l标记的胰岛素解离增强。这些受体对胰岛素原、IGF-II和IGF-I的交叉反应性分别为4%、1.8%和<1%。标记胰岛素与BLM胰岛素受体与二琥珀酰亚基共价交联发现单个135,000-Mr带完全被未标记胰岛素抑制。胰岛素与BLM的特异性结合（39.0±2.4%）比与BBM的特异性结合（2.5±0.6%）高16倍。这些结果表明，狗小肠粘膜的血管表面存在一种高度特异性的胰岛素受体，而不是管腔表面，这表明胰岛素可能在胃肠道生理调节中发挥重要作用。
Little is known about hormonal regulation of substrate transport and metabolism in the mucosal lining of the small intestine. Because insulin regulates these functions in other tissues by binding to its receptor, we have investigated the presence of insulin receptors in canine small intestinal mucosa with basolateral membranes (BLM) and brush border membranes (BBM) prepared by sorbitol density centrifugation. A14-[125l]iodoinsulin was used to study binding and structural characteristics of specific insulin receptors in BLM. Analysis of receptors in BLM identified binding sites with high affinity (Kd 88 pM) and low capacity (0.4 pmol/mg protein) as well as with low affinity (Kd 36 nM) and high capacity (4.7 pmol/mg protein). Binding was time, temperature, and pH dependent, and 125l-labeled insulin dissociation was enhanced in the presence of unlabeled insulin. Cross-reactivity of these receptors to proinsulin, IGF-II, and IGF-I was 4,1.8, and <1%, respectively. Covalent cross-linking of labeled insulin to BLM insulin receptors with disuccinimidyl suberate revealed a single 135,000-Mr band that was completely inhibited by unlabeled insulin. There was a 16-fold greater specific binding of insulin to BLM (39.0 ± 2.4%) than to BBM (2.5 ± 0.6%). These results demonstrate the presence of a highly specific receptor for insulin on the vascular, but not the luminal, surface of the small intestinal mucosa in dogs, and suggest that insulinmay play an important role in the regulation of gastrointestinal physiology.
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血管活性肠多肽优先结合大鼠和兔肠细胞的基底外侧膜。
DOI：
10.1172/jci110748
发表时间：
1983
期刊：
The Journal of clinical investigation
影响因子：
--
作者：
Dharmsathaphorn,K;Harms,V;Yamashiro,DJ;Hughes,RJ;Binder,HJ;Wright,EM
通讯作者：
Wright,EM
结肠上皮细胞粘膜表面胰岛素受体的鉴定。
DOI：
--
发表时间：
1985
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Pillion,DJ;Ganapathy,V;Leibach,FH
通讯作者：
Leibach,FH
犬肾基底外侧膜中胰岛素刺激的磷酸化和胰岛素结合。
DOI：
10.1152/ajprenal.1984.247.3.f408
发表时间：
1984
期刊：
The American journal of physiology
影响因子：
--
作者：
Hammerman,MR;Gavin3rd,JR
通讯作者：
Gavin3rd,JR
胰岛素刺激来自近端管状节段的刷状缘囊泡中的 Pi 运输。
DOI：
10.1152/ajpendo.1984.247.5.e616
发表时间：
1984
期刊：
The American journal of physiology
影响因子：
--
作者：
Hammerman,MR;Rogers,S;Hansen,VA;Gavin3rd,JR
通讯作者：
Gavin3rd,JR