Figure 2: GRK2 activiation in cavernosal tissue. (a) GRK2 localization was assessed by immunohistochemistry (magnification x200, scale bars = 50 μm). (b) Bar graphs represent quantitative image analysis for immunohistochemistry. (c) The expression of GRK2 mRNA was measured by real-time quantitative PCR. The data were presented as the fold change relative to the non-diabetic control. (d) GRK2 protein expression was measure by western blot analysis. β-actin was used as a loading control. (e) Expression levels of GRK2 protein were normalized to β-actin. Results were reported as mean ± standard deviation (s.d.). P < 0.05, the indicated group versus control group; *P < 0.05, the indicated group versus T2DM+vehicle group, n = 20 per group. All results are representative of three independent experiments. GRK2: G protein-coupled receptor kinase 2; T2DM: type 2 diabetes mellitus, PCR: polymerase chain reaction.