Cyclic adenosine 3',5'-monophosphate regulates GLUT4 and GLUT1 glucose transporter expression and stimulates transcriptional activity of the GLUT1 promoter in muscle cells.

摘要: We have previously reported that innervation-dependent basal contractile activity regulates in an inverse manner the expression of GLUT1 and GLUT4 glucose transporters skeletal muscle. Based on facts muscle innervation decreases denervation increases cAMP levels, we investigated whether might mediate effects innervation/denervation transporter expression. Treatment L6E9 myotubes with 8-bromo-cAMP, forskolin, or monobutyryl-8-bromo-cAMP led to a marked decrease protein levels; 8-bromo-cAMP also diminished messenger RNA (mRNA), suggesting pretranslational repression. In contrast, myoblasts responded forskolin by increasing cell content protein. Induction was consequence activation different mechanisms myoblast myotube cells; whereas treatment caused substantial increase mRNA myoblasts, no change detected myotubes...