A comparison of insulin binding by liver plasma membranes of rats fed a high glucose diet or a high fat diet.
A comparison of insulin binding by liver plasma membranes of rats fed a high glucose diet or a high fat diet.
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喂食高葡萄糖饮食或高脂肪饮食的大鼠肝脏质膜胰岛素结合的比较。
DOI：
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发表时间：
1977
影响因子：
6.5
通讯作者：
J. Tepperman
中科院分区：
文献类型：
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作者：
J. Sun;H. Tepperman;J. Tepperman
从特异性结合、胰岛素降解、结合位点降解以及激素结合和解离速率方面研究了（125）I标记的胰岛素与喂食高脂肪（L）饮食或高糖（G）饮食的大鼠的纯化肝质膜的相互作用。Scatchard分析表明，G和L饮食适应大鼠的膜存在高和低亲和力的结合位点。然而，高葡萄糖饮食大鼠的肝质膜比高脂肪饮食大鼠的膜结合了50%以上的胰岛素。饮食不改变胰岛素结合位点降解。结果表明，与葡萄糖喂养相比，与脂肪喂养相关的胰岛素结合位点数量明显减少（G = 10.2 +/- 2.45 x 10（-12）mol/mg膜蛋白，L = 4.5 +/- 1.73 x 10（-12）mol/mg膜蛋白）是高脂饮食大鼠膜胰岛素结合减少的原因。还研究了伴刀豆球蛋白A（Con A）对胰岛素与肝质膜结合的影响。Con A在低于50 μ g/ml的浓度下增强了胰岛素与大鼠肝脏质膜的特异性结合，而在高于50 μ g/ml的浓度下，Con A抑制胰岛素与这些膜的结合。在低浓度下刀豆蛋白A对胰岛素结合的刺激作用较大，而在高浓度下对结合的抑制作用较小。这些结果表明，饲料可以改变质膜糖蛋白。
The interaction of (125)I-labeled insulin with purified liver plasma membrane from rats fed a high fat (L) diet or a high glucose (G) diet was studied with respect to specific binding, insulin degradation, binding site degradation, and rate of hormone association and dissociation. Scatchard analysis suggested the presence of high and low affinity binding sites for membranes of both G and L diet-adapted rats. However, liver plasma membrane from rats fed the high glucose diet bound 50% more insulin than did membrane from rats fed the high fat diet. Diet did not change insulin binding site degradation. The results suggested that an apparently reduced number of insulin binding sites (G = 10.2 +/- 2.45 x 10(-12) mol/mg membrane protein, L = 4.5 +/- 1.73 x 10(-12) mol/mg membrane protein) associated with fat feeding as compared to glucose feeding was responsible for the reduced insulin binding by membrane from rats fed the high fat diet. The effects of concanavalin A (Con A) on insulin binding to liver plasma membranes were also investigated. Con A enhanced the specific binding of insulin to liver plasma membranes from rats fed either diet at concentrations lower than 50 micro g/ml, whereas at concentrations higher than 50 micro g/ml Con A inhibited insulin binding to these membranes. The stimulatory effect of Con A on insulin binding at low concentrations was greater and inhibition of binding at high concentration was less in the case of membrane prepared from L diet-adapted animals. These results suggested that diet can modify the plasma membrane glycoproteins.