AR and Hyperglycemia: Since AR is induced by hyperglycemia (≥20 mM glucose; 5 mM being normoglycemic) (González et al., 1984; Tawata et al., 1992) and the DMEM-HG culture medium contains 25 mM glucose, we also measured the dependence of the expression of gene Akr1b3 (which codes for mouse AR) on glucose as an indirect and complementary test for AR activity.