Figure 6: Cavernous protein and cGMP levels. (a) Representative western blot results of vWF, α-SMA, and GAPDH. (b) α-SMA protein expression level examined by western blot. (c) vWF protein expression level examined by western blot. (d) cGMP levels were measured by ELISA. *P < 0.05; **P < 0.005. DMED: rats with diabetes mellitus-associated erectile dysfunction; Sil: sildenafil; PK: pancreatic kininogenase; cGMP: cyclic guanosine monophosphate; α-SMA: α-smooth muscle actin; vWF: von Willebrand factor; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; ELISA: enzyme-linked immunosorbent assay.