In an effort to investigate the mechanism by which the AR deletion mediated the beneficial effect on degeneration of retinal capillaries in diabetes, we measured several parameters related especially to inflammation and nitrative (oxidative) stress, these being physiologic and molecular abnormalities that have been found in other studies to be associated with (and possibly causally related to) the development of the early stages of diabetic retinopathy. Here, AR is linked to diabetes mellitus.