Figure 3.

Impairment of visual function in nondiabetic and diabetic C57Bl/6J mice, opsin^−/− mice, and P23H mutant mice compared to C57Bl/6J control mice at 9 months of age (7 months of diabetes). (a) Spatial frequency threshold and contrast sensitivity were significantly reduced in diabetic C57Bl/6J mice compared to nondiabetic controls, whereas responses in both opsin mutant groups were largely absent. (b) ERG responses were partially (but not significantly) reduced in diabetic C57Bl/6J mice compared to nondiabetic controls, whereas responses in Rho^P23H/P23H mutants were largely absent. Opsin^−/− mice were not tested. The representative waveforms for both the dark- and light-adapted responses are in response to a 1.4 log cd s/m² stimulus. n = 5 to 7 per group.