Study Of The Intracellular Mechanism About Electrical Stimulation Promotes GLUT4 Translocation In Skeletal Muscle Of Type 2 Diabetic Rats

Partâ… Objective: To observe the effects of electrical stimulation on glut4 translocation in skeletalmuscle of OLETF rats.Method: Musculus extensor digitorum longus were isolated from twenty Otsuka Long-EvansTokushina Fatty(OLETF) rats and twenty Sprague Dawley rats. The skeletal muscles of OLETFrats and SD rats are randomly assigned to one of six groups according to different interventions:electrical stimulation group, non-electrical stimulation group, LY294002 with electricalstimulation group, LY294002 group, Compound C with electrical stimulation group andCompound C group. The distributions of GLUT4 in skeletal muscles were observed byimmunofluorescence.Results: 1. Immunofluorescence showed that the expressions of GLUT4 on the cell membrane inall electrical stimulated groups of OLETF rats were markly higher than those in correspondingnon-electrical stimulated groups. 2. The expressions of GLUT4 on the cell membrane in allelectrical stimulated groups of SD rats were also markly higher than those in correspondingnon-electrical stimulated groups.Conclusion: 1. Skeletal muscle contractions induced by electrical stimulation resulted in thetranslocation of GLUT4 from intracellular membranes to the cell surface. 2. Blocking AMPK orPI3K signaling pathway could not inhibit GLUT4 translocation induced by electrical stimulation.Partâ…¡Objective: To observe the effects of electrical stimulation on AMPK, PI3K, Akt and Erk in skeletal muscle of OLETF rats, and to explore the intracellular mechanism about how Skeletal muscle contraction induced by electrical stimulation promotes GLUT4 translocation in OLETF rats.Method: Musculus extensor digitorum longus were isolated from eight Otsuka Long-EvansTokushina Fatty(OLETF) rats and eight Sprague Dawley rats. The skeletal muscles of OLETF ratsand SD rats are respectively divided into two groups: electrical stimulation group andnon-electrical stimulation group. AMPK, PI3K, Akt and ERK proteins were detected by westernblot analysis.Results: 1. Western blot analysis showed that the phosphorylation level of AMPK, PI3K and Aktincreased obviously after electrical stimulated muscle contraction in OLETF rats or SDrats(P<0.01). 2. However, There was no significant difference in the phosphorylation level of ERKbetween electrical stimulated groups and Non-electrical stimulated groups in OLETF rats or SDrats (P>0.05).Conclusion: Skeletal muscle contractions induced by electrical stimulation resulted in GLUT4translocation and glucose transport through AMPK and PI3K/Akt signaling pathways.Partâ…¢Objective: To observe the effects of inhibitors of AMPK and PI3K on signaling pathways stimulated by electricity in skeletal muscle, and to explore the effects of AMPK and PI3K on GLUT4 translocation in skeletal muscle.Method: Musculus extensor digitorum longus were isolated from twenty Otsuka Long-Evans Tokushina Fatty(OLETF) rats and twenty Sprague Dawley rats. The skeletal muscles of OLETF rats are randomly assigned to one of six groups according to different interventions: electrical stimulation group, non-electrical stimulation group, LY294002 with electrical stimulation group, LY294002 group, Compound C with electrical stimulation group and Compound C group. The skeletal muscles of SD rats are divided in the same way. AMPK, PI3K and Akt proteins were detected by western blot analysis.Results: 1. Western blot analysis showed that the phosphorylation level of AMPK in LY294002 with electrical stimulated group was significantly higher than that in LY294002 group in OLETF rats or SD rats(P<0.01). 2. The phosphorylation level of PI3K and Akt also increased obviously in Compound C with electrical stimulated group compared with Compound C group in OLETF rats or SD rats(P<0.01).Conclusion: 1. Skeletal muscle contractions induced by electrical stimulation resulted in GLUT4translocation and glucose transport through AMPK and PI3K/Akt signaling pathways. Blockingone of these pathways could not inhibit GLUT4 translocation.