 Immunohistology has shown that PDE5 localizes in heart cells at the sarcomere z-disk, but can also be found in diffuse amounts in the cytosol.Increased expression of PDE5 has also been measured in hypertrophic disease and has been linked to oxidative stress, and PDE5 inhibition has shown beneficial effects in the failing heart.In an experiment, PDE5 overexpression was found to contribute to worsened pathological remodeling after mouse cardiomyocytes experienced myocardial infarction.