The genetically diabetic db/db mouse is a model of type-2 diabetes, where nephropathy and neuropathy, but not retinopathy were observed. The authors studied the retinas (trypsin digestion technique) of 16 db/db mice and 16 age-matched litter mates (db/m; controls), divided into five age groups. They noted a marked increase in the ratio of endothelial cells to intramural pericytes in diabetic mice compared to controls. This increase resulted from a selective and highly significant loss of pericytes in db/db mice (p < 0.05). Some strand-like and relatively acellular capillaries were also observed. The db/db mouse may represent an adequate model for studies on the pathogenesis of retinopathy.