부산대학교 도서관

Microcurrent electrical neuromuscular stimulation (MENS) isknown as an extracellular stimulus for the regeneration of injuredskeletal muscle in sports medicine. However, the effects ofMENS-associated increase in muscle protein content are not fullyclarified. The purpose of this study was to investigate the effectsof MENS on the muscular protein content, intracellular signals,and the expression level of caveolin-3 (Cav-3), tripartite motifcontaining 72 (TRIM72) and MM isoenzyme of creatine kinase(CK-MM) in skeletal muscle using cell culture system. C2C12myotubes on the 7th day of differentiation phase were treatedwith MENS (intensity: 10-20 μA, frequency: 0.3 Hz, pulse width:250 ms, stimulation time: 15-120 min). MENS-associatedincrease in the protein content of myotubes was observed,compared to the untreated control level. MENS upregulated theexpression of Cav-3, TRIM72, and CK-MM in myotubes.A transient increase in phosphorylation level of Akt was alsoobserved. However, MENS had no effect on the phosphorylationlevel of p42/44 extracellular signal-regulated kinase-1/2 and5’AMP-activated protein kinase. MENS may increase muscleprotein content accompanied with a transient activation of Aktand the upregulation of Cav-3 and TRIM72.