Figure 4: Changes in eNOS-NO-cGMP Pathway. (a) The expression of eNOS and phospho-eNOS (Ser1177) detected with Western blot. (b) Relative density of eNOS and phospho-eNOS (Ser1177) compared with β-actin. Data are shown as the fold changes over the control group. n = 4 for each group. (c) eNOS expression detected with immunohistochemistry (×400). Location of eNOS was indicated with black arrow. (d) eNOS-positive area in the corpus cavernosum detected with immunohistochemistry. n = 3 for each group. (e) NO concentration detected using a total NO assay kit and normalized by the protein concentration. n = 3 for each group. (f) cGMP concentration measured with an enzyme-linked immunosorbent assay kit and normalized by the protein concentration. n = 3 for each group. Statistical analyses were conducted using one-way analysis of variance followed by the Tukey test. *P < 0.05, compared with control group. #P < 0.05, compared with DM group. DM: diabetes mellitus; eNOS: endothelial nitric oxide synthase; NO: nitric oxide; cGMP: cyclic guanosine monophosphate.