Rapid insertion of GLUT2 into the rat jejunal brush-border membrane promoted by glucagon-like peptide 2
Rapid insertion of GLUT2 into the rat jejunal brush-border membrane promoted by glucagon-like peptide 2
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DOI：
10.1042/bj20020393
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发表时间：
2002-10-01
影响因子：
4.1
通讯作者：
Cheeseman, CI
中科院分区：
文献类型：
--
作者：
Au, A;Gupta, A;Cheeseman, CI
利用肠腔体内灌注以及膜蛋白分离和免疫组化研究了胰高血糖素样肽2（GLP-2）影响下大鼠空肠刷状缘膜（BBM）中GLUT 2瞬时表达的可能作用。体内血管输注GLP-2使果糖吸收速率增加一倍，并且这种增加可以被管腔根皮素阻断。免疫组化显示GLUT 2在大鼠空肠成熟肠上皮细胞的基底侧和BBM中均有表达。用50 mM D-葡萄糖灌注肠腔或血管输注800 pM GLP-2 1 h可增加BBM中GLUT 2的表达。使用生物素化的表面暴露蛋白质的Western印迹定量这些变化显示BBM中GLUT 2的表达加倍，但葡萄糖和GLP-2的作用不是累加的。这些结果表明，血管GLP-2可以促进GLUT 2插入大鼠空肠BBM，为膳食己糖提供低亲和力/高容量的进入途径。
A possible role for GLUT2 transiently expressed in the rat jejunal brush-border membrane (BBM) under the influence of glucagon-like peptide 2 (GLP-2) was investigated using in vivo perfusion of the intestinal lumen as well as isolation of membrane proteins and immunohistochemistry. A I h vascular infusion of GLP-2 in vivo doubled the rate of fructose absorption and this increase could be blocked by luminal phloretin. Immunohistochemistry of frozen sections of rat jejunum showed the expression of GLUT2 in both the basolateral and BBMs of mature enterocytes. Perfusion of the intestinal lumen with 50 MM D-glucose or vascular infusion of 800 pM GLP-2 for 1 h increased the expression of GLUT2 in the BBM. Quantification of these changes using Western blotting of biotinylated surface-exposed protein showed a doubling of the expression of GLUT2 in the BBM, but the effects of glucose and GLP-2 were not additive. These results indicate that vascular GLP-2 can promote the insertion of GLUT2 into the rat jejunal BBM providing a low-affinity/high-capacity route of entry for dietary hexoses.