Fig. 3

Overexpression of AR further increased 15% stretch-induced pro-proliferation, approaching to the pro-proliferation degree of 15% stretched C2C12 myoblasts. L6 cells were seeded onto flexible-bottomed 6-well plates and transfected with pcDNA3.1 vector or pcDNA3.1-AR recombinant plasmid (2.5 μg/well) using LipoPlus™ reagent. After 24 h incubation, L6 cells were subjected to 15% stretch at 0.5 Hz lasting for 6 h or left un-stretched. After another 24 h incubation, the changes in (a) the AR level and (b) the proliferation of L6 cells in un-stretched and 15% stretched conditions were compared between transfection with pcDNA3.1-AR recombinant plasmid and with pcDNA3.1 vector. *p < 0.05 vs CON_pcDNA3.1; ^#p < 0.05 vs 15% stretch_pcDNA3.1. The differences in (c) the AR level and (d) the pro-proliferation extents after 15% stretch were compared between L6 myoblasts transfected with pcDNA3.1-AR and C2C12 myoblasts. *p < 0.05 vs 15% stretched L6 myoblasts_pcDNA3.1-AR (c) or 15% stretched L6 myoblasts_pcDNA3.1 (d). The pro-proliferation extents of 15% stretched L6 and C2C12 cells were calculated using the formula: = (OD_{15% stretch}-OD_CON)/OD_CON; and for stretched L6 myoblasts transfection with pcDNA3.1-AR recombinant plasmid using the following formula: = (OD_{15% stretch+pcDNA3.1-AR}-OD_CON+pcDNA3.1)/OD_CON+pcDNA3.1. The experiments were repeated at least three times, and the results were from three independent experiments and represented as mean ± SD