A regulação da expressão gênica do GLUT4 induzida pelo jejum e insulina em músculo sóleo de ratos e a participação do fator transcricional Nuclear Factor -kappa B (NF-kB). Investigou-se a regulação induzida pelo jejum e insulina na expressão do GLUT4 no músculo sóleo de rato Wistar e a participação do fator transcricional NF-kB. Analisou-se sóleo de rato alimentado e jejuado com músculo incubado ou não em KHB com ou sem insulina. Avaliou-se a expressão do GLUT4 por Northern e Western blotting e a atividade de ligação do NF-kB ao DNA por Gel Shift. Sóleos de ratos jejuados diminuíram em 24% o mRNA de GLUT4, aumentaram 51% a atividade de ligação do NF-kB e diminuíram 30% o conteúdo protéico total comparados aos alimentados. Sóleos de ratos jejuados aumentaram 38% o mRNA do GLUT4, diminuíram 30% a atividade de ligação do NF-kB e sem alterar a proteína GLUT4 comparados aos incubados. A incubação com insulina por 70, 120 e 180 minutos do sóleo de ratos jejuados aumentou o mRNA de GLUT4 em 37%, 30% e 25%, diminuiu a atividade de ligação do NF-kB em 30%, 40% e 50% e aumentou a proteína GLUT4 em 33%, 40% e 50% em relação a incubação com KHB. Os resultados indicam que o jejum e insulina regulam a expressão de GLUT4 com participação do NF-kB.

The regulation of GLUT4 gene expression induced by fasting and insulin in soleus muscle of rats and the participation of transcriptional factor Nuclear Factor -kappa B (NF-kB). It was investigated the regulation induced by fasting and insulin in the GLUT4 expression in soleus muscle of Wistar rat and the particiation of transcriptional factor NF-kB. It was analysed soleus of fed-rats and fasted-rats with muscle incubated ou not in KHB with or without insulin. It was analysed the GLUT4 expression for Northern and Western blotting and the binding activity of NF-kB to DNA for Gel Shift. Soleus of fasted-rats decreased 24% the GLUT4 mRNA, increased 51% the binding activity of NF-kB and decreased 30% the total protein content compared to fed-rats. Soleus of fasted-rats increased 38% the GLUT4 mRNA, decreased 30% the binding activity of NF-kB, without altering the GLUT4 protein compared to the incubated muscles. The incubation with insulin for 70, 120 e 180 minutes of the soleus of fasted-rats increased the GLUT4 mRNA in 37%, 30% e 25%, decreased the binding activity of NF-kB in 30%, 40% e 50% and increased GLUT4 protein in 33%, 40% e 50% in relation to incubated muscles with KHB. The results indicate that fasting and insulin regulate the GLUT4 expression with participation of NF-kB.