L-Arginine Stimulates Fibroblast Proliferation through the GPRC6A-ERK1/2 and PI3K/Akt Pathway
Figure 3
Effects of l-arginine stimulation on the activities of ERK, Akt, PKA and CREB.
(A, B, C, D) ERK, Akt, PKA and CREB activities were analyzed by immunoblotting at 5, 15, and 30 min after stimulation with 6 mM l-arginine. Densitometry measurements for p-ERK, p-Akt, p-PKA and p-CREB were normalized to the amount of total ERK, Akt, PKA and CREB, respectively. (E) Fibroblasts were treated with 10 μM U0126, and then cells were stimulated with 6 mM l-arginine. The activities of CREB were analyzed by immunoblotting. Results are presented as the fold change compared with untreated cells. Data are expressed as the mean ± SEM of 3 independent experiments (*p<0.05, **p<0.01, Tukey’s post hoc test).