AGT and diabetic retinopathy: The following keywords were used and combined to narrow down the literature: IOP (41729), RAS (29132), tissue RAS (6080), angiotensin (116858), angiotensin I (8316), angiotensin II (59230), angiotensin (1-7) (1278), angiotensin (1-9) (73), angiotensin (3-4) (10) angiotensin converting enzyme 1 (238) and -2 (1453), Mas receptor (445), angiotensin receptor (17975), eye disease (5611), glaucoma (59565), diabetic retinopathy (DR) (26740), retinopathy of prematurity (ROP) (6638) and age-related macular degeneration (AMD) (13303).