Effect of diet and exercise on endothelial nitric oxide synthase (eNOS) dimers/monomers in the penis. (A) Representative Western immunoblot of eNOS dimers and eNOS monomers in the penes of NFSe (line 1), NFEx (line 2), HFSe (line 3), and HFEx (line 4) pigs. (B) Quantitative analysis of eNOS dimers/monomers in the penes of NFSe, NFEx, HFSe, and HFEx pigs. The ratio of eNOS dimers to monomers was reduced in HFSe pig penes compared to NFSe pig penes, and this was prevented by exercise. Each bar represents the standard error of the mean (SEM). a = P < 0.05 vs. NFSe; N = 8; NF = normal-fat diet; HF = high-fat diet; Se = sedentary; Ex = exercised.