Jóhannsson E, McCullagh K J, Han X X, Fernando P K, Jensen J, Dahl H A, Bonen A
Norwegian University of Physical Education and Sport, Oslo, Norway.
Am J Physiol. 1996 Sep;271(3 Pt 1):E547-55. doi: 10.1152/ajpendo.1996.271.3.E547.
To examine the effects of GLUT-1 on GLUT-4-dependent, insulin-stimulated, and contraction-stimulated 2-deoxy-D-glucose (2-DG) transport, we overexpressed GLUT-1 in metabolically heterogeneous skeletal muscles [red and white tibialis anterior (TA) and extensor digitorum longus (EDL)] via 7 days of chronic electrical stimulation. GLUT-1 was increased 1.6- to 16.4-fold (P < 0.05). Basal 2-DG transport was increased 1.7- to 3.0-fold (P < 0.05) and was equal to (red TA and EDL; P > 0.05) or exceeded insulin-stimulated 2-DG transport by 50% (white TA; P < 0.05) in the control muscles. GLUT-4 was concomitantly overexpressed (2.1- to 4.4-fold; P < 0.05). Insulin-stimulated 2-DG transport was increased 1.6- to 2.5-fold (P < 0.05). During muscle contractions, 2-DG transport increased 9- to 12-fold (P < 0.05) in control muscles, but this was reduced by approximately 25% (P < 0.05) in muscles overexpressing GLUT-1 and GLUT-4 (red TA and EDL). In contrast, in the experiment, white TA contraction-stimulated 2-DG transport was increased 1.7-fold (P < 0.05). Therefore, overexpression of GLUT-1, when GLUT-4 is also overexpressed, does not impair insulin-stimulated 2-DG transport, although contraction-stimulated transport may be reduced in some muscles.
为了研究葡萄糖转运蛋白1（GLUT-1）对依赖葡萄糖转运蛋白4（GLUT-4）、胰岛素刺激以及收缩刺激的2-脱氧-D-葡萄糖（2-DG）转运的影响，我们通过7天的慢性电刺激使GLUT-1在代谢异质性的骨骼肌[红色和白色胫骨前肌（TA）以及趾长伸肌（EDL）]中过表达。GLUT-1增加了1.6至16.4倍（P<0.05）。在对照肌肉中，基础2-DG转运增加了1.7至3.0倍（P<0.05），并且等于红色TA和EDL中的胰岛素刺激的2-DG转运（P>0.05），或者超过白色TA中胰岛素刺激的2-DG转运50%（P<0.05）。GLUT-4同时过表达（2.1至4.4倍；P<0.05）。胰岛素刺激的2-DG转运增加了1.6至2.5倍（P<0.05）。在肌肉收缩期间，对照肌肉中的2-DG转运增加了9至12倍（P<0.05），但在过表达GLUT-1和GLUT-4的肌肉（红色TA和EDL）中，这一增加减少了约25%（P<0.05）。相比之下，在该实验中，白色TA的收缩刺激的2-DG转运增加了1.7倍（P<0.05）。因此，当GLUT-4也过表达时，GLUT-1的过表达不会损害胰岛素刺激的2-DG转运，尽管在某些肌肉中收缩刺激的转运可能会减少。
