Karnieli E, Barzilai A, Rafaeloff R, Armoni M
J Clin Invest. 1986 Oct;78(4):1051-5. doi: 10.1172/JCI112660.
We examined insulin's effects on glucose transport and on subcellular transporter distribution in isolated human omental adipocytes of various sizes. Insulin stimulated 3-O-methylglucose transport by twofold in small cells, while a smaller and insignificant effect was measured in large cells. In the small cells, basal concentrations of glucose transporters were 2.9 and 17.2 pmol/mg membrane protein in the plasma and the low density microsomal membranes, respectively. Increasing cell size was associated with a 50% decrease in the concentration of transporters in each fraction, with no change in their total number per cell. Insulin stimulated the translocation of transporters from the intracellular pool to the plasma membranes, irrespective of cell size. Thus, insulin resistance at the postreceptor level, observed in human obesity, may be associated with a relative depletion of total transporters per cell together with a reduction in their intrinsic activity at the plasma membrane level.
我们研究了胰岛素对不同大小的分离人网膜脂肪细胞中葡萄糖转运及亚细胞转运体分布的影响。胰岛素使小细胞中的3 - O - 甲基葡萄糖转运增加了两倍，而在大细胞中测得的影响较小且不显著。在小细胞中，血浆和低密度微粒体膜中葡萄糖转运体的基础浓度分别为2.9和17.2 pmol/mg膜蛋白。细胞大小增加与每个组分中转运体浓度降低50%相关，而每个细胞中转运体的总数没有变化。胰岛素刺激转运体从细胞内池转运到质膜，与细胞大小无关。因此，在人类肥胖中观察到的受体后水平的胰岛素抵抗，可能与每个细胞中总转运体的相对耗竭以及它们在质膜水平的内在活性降低有关。
