［B3－Lys］－胰岛素的研究：受体结合及生物活性  

Study on [B_3-Lys]-Insulin: Receptor Binding and Biological Activity

作　　者：张新堂[1] 徐明华[1] 叶莺[1] 许英镐[1] 朱尚权[1] 

机构地区：[1]中国科学院上海生物化学研究所

出　　处：《生物化学与生物物理学报》1994年第3期277-282,共6页

基　　金：国家自然科学基金

摘　　要：本文用１２５Ｔ－［Ｂ３－Ｌｙｓ］－胰岛素和１２５Ⅰ－胰岛素研究了［Ｂ３－Ｌｙｓ］－胰岛素和胰岛素与人胎盘细胞膜（ＨＰＭ）胰岛素受体结合特性并进行了比较。实验结果表明［Ｂ３－Ｌｙｓ］－胰岛素与ＥＰＭ胰岛素受体结合能力比天然猪胰岛素高。由竞争取代曲线得到的［Ｂ３－Ｌｙｓ］－胰岛素和猪胰岛素的ＩＣ（５０）值分别为０．６５和１．１１ｎｍｏｌ／Ｌ。经Ｓｃａｔｃｈａｒｄ分析得出［Ｂ３－Ｌｙｓ］－胰岛素与ＨＰＭ胰岛素受体中高亲和位点和低亲和位点结合的亲和常数分别为１．７２×１０９和２．２７×１０６Ｌ／ｍｏｌ，而猪胰岛素分别为１．２６×１０９和１．４７×１０６／ｍｏｌ。促脂肪细胞合成脂肪实验结果表明［Ｂ３－Ｌｙｓ］－胰岛素也同样具有比天然猪胰岛素更高的离体生物活力，ＥＣ（５０）分别为０．１７５和０．３０１ｎｍｏｌ／Ｌ。可见［Ｂ３－Ｌｙｓ］－胰岛素的受体结合能力和高体生物活力都为猪胰岛素的１．７倍。The receptor binding Properties of [B3--Lys]-insulin and insulin in human placental membrane were studied and compared by using their 125I-labled forms as ligand. The results Showed that the receptor binding capacity of [B3-Lys]insulin is higher than that of native porcine insulin, with IC(50) to be 0.65nM and 1.11nM respectively. The affinity constants calculated by Scatchard method were 1 .72×109 M-1 and 2. 27×106 M-1 for both high and low affinity sites with [B3-Lys]-insulin; 1 .26×109 M-1 and 1 .47×106 M-1 for those of insulin. The biological activity of [B3-Lys]-insulin is also higher than that of native porcine insulin in terms of the ability to stimulate glucose incorporation into lipids in rat adipocytes, with EC(50) to be 0 .175 nM and 0.301 nM respectively. So, it seemed that[B3-Lys]-insulin was 1 .7 fold as potent as native porcine insulin in both the receptor binding capacity and biological activity in vitro.

关 键 词：胰岛素 受体 结合 生物活力 

分 类 号：Q578[生物学—生物化学]