Effect of endogenous insulin-like growth factor and stem cell factor on diabetic colonic dysmotility

Figure 4 Insulin-like growth factor-1-induced stem cell factor expression through the extracellular-signal-regulated kinase 1/2 pathway in smooth muscle cells. A: Insulin-like growth factor-1 (IGF-1) effects on the expression of stem cell factor (SCF) as a function of concentration after treatment with IGF-1 for 24 h. ^bP < 0.01 vs 0 ng/mL IGF-1; ^dP < 0.01 vs 50 ng/mL IGF-1; B: IGF-1 effects on SCF expression as a function of time. ^aP < 0.05, ^bP < 0.01 vs 0 h; C: Phosphorylation of extracellular-signal-regulated kinase 1/2 (ERK1/2) and Akt after 100 ng/mL IGF-1 treatment for 15 min; D: Effects of PD98059 and LY294002 on SCF expression by IGF-1 treatment. ^bP < 0.01 vs the no treatment group; ^dP < 0.01 vs IGF-1 treatment group. Western blotting represent 3 independent experiments. α-Tubulin was used as a loading control (each bar represents the mean ± SE of 3 independent experiments).