Role of Glut1 glucose transporter activation in stimulation of glucose transport by A231876 and TPA.
Role of Glut1 glucose transporter activation in stimulation of glucose transport by A231876 and TPA.
复制标题
Glut1 葡萄糖转运蛋白激活在 A231876 和 TPA 刺激葡萄糖转运中的作用。
DOI：
10.1042/bst026s289
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发表时间：
1998
影响因子：
3.9
通讯作者：
Beigi,FI
中科院分区：
文献类型：
--
作者：
Koseoglu,MH;Beigi,FI
We first measured the glucose uptake in Clone 9 cells and transfected cells. Glucose uptake was 3 fold higher in transfected cells under basal conditions due to the higher expression of Glut I in this cell line compared to the nontransfected Clone 9 cells. We next determined the effect of A23187 and TPA on glucose transport rate in transfected cells. Exposure to 2 fl A23187 or 0.1 pM TPA for 1 hr resulted in 2.6 and 2.4 fold increases in glucose uptake respectively (Fig. I). We also showed that there was no increase in cellular Glutl content in the acute stimulation of glucose transport with A23187 or TPA. To elucidate the molecular mechanisms involved in the stimulation of glucose transport in response to incubation of A23 I87 or TPA, we used a direct sensitive method to detect Glutl immunologically on the cell surface employing transfected cells expressing Glutlmyc (3). There was no significant difference in the amount of antibody bound to myc epitopes on the surface of control and stimulated cells (Fig. 2). In addition, quantitation of the fluorescence intensity of intact cells and plasma membrane sheets (Fig. 3) and the Glutl content of plasma membrane in western blot analysis by anti-Glut1 and anti-myc antibodies (Fig. 4) showed no difference in control or cells stimulated with A23 187 or TPA.The early and marked stimulation of glucose transport by A23 187 or TPA in Clone 9 cells is not associated with any increase in plasma membrane Glut1 content. The results strongly suggest that the enhanced rate of transport under such conditions is mediated by activation of transporters pre-existing in the plasma membrane. Mechanisms resulted in the activation of Glutl by A23 187 and TPA remain to be elucidated.
