Figure 5: eNOS-positive smooth muscle in corpus cavernosum. Representative immunofluorescence staining of eNOS (red, indicated by arrows) expression in (a) control, (b) DMED, (c) DMED + Sil, (d) DMED + PK, and (e) DMED + Sil + PK groups. Scale bars = 100 μm. (f) Semi-quantification results of eNOS expression (presented as eNOS-positive cells/total cells ± s.d.) in each group. *P < 0.05; **P < 0.005. DMED: rats with diabetes mellitus-associated erectile dysfunction; Sil: sildenafil; PK: pancreatic kininogenase; eNOS: endothelial nitric oxide synthase; s.d.: standard deviation.